| Author | Topic |
|---|
Toymods Social Secretary
Location:
Sydney
Registered:
July 2002
|
|
4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 02:39
|
 |
in response to an email i recently received from ppc@dnet.aunz.com i would like to dispell all misinformation about BOTH the 8.0:1 and 8.9:1 4A-GZE pistons.
These pistons in standard form are both FORGED and ceramic coated even.
They are not "semi-forged", honestly i dont think such a think exists.
Evideciary support in the three threads below:
GZE piston analysis part 1
GZE piston analysis part 2
GZE piston analysis part 3
Finally... here is a picture to demonstrate the forged grain structure in a 4A-GZE piston for those too lazy to even click a link....
Now stop emailing me with abusive messages.
|
|
|
Toymods Social Secretary
Location:
Sydney
Registered:
July 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 05:32
|
|
P.S. the anonymous emailler has been identified as none other than the one, the only, the BIGGEST....
... Smuggla
|
|
|
Club Member
Location:
sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 09:02
|
|
haha good ol smuggla  that email address is gona get hammered 
|
|
|
I supported Toymods
Location:
Epping, Sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 09:29
|
|
|
you'd think after stewart went to the trouble of disecting, cleaning, rubbing down and hitting with assorted electron microscopes and particle beams that people would accept it as truth :\
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 10:27
|
|
well, since thesis is finishing up this week, i'll start to do some more in-depth analysis.... first thing i think is to confirm the coating composition.
first will be X-ray diffraction. that should tell if it is alumina or any other kind of ceramic.
if that doesn't resolve it, i will then try RAMAN spectroscopy, and look at the bond energies, that should sort it out if it is a polymer (it is vaguely possible)
as for the forged.. they LOOK like forged. i have been chatting with some professors abotu it, and they suggest they might have been "semi-solid formed" or "Squeeze cast", which basically means the metal is pushed in under pressure in a mushy state.. this would have been a fairly advanced process for the late 80's and i have a stack of articles on it..
either way, we will get to the bottom of it.
what we DO know, is that there are flow-lines reminiscent of forging, and that there is a 15micron layer.
i'll get back to y'all in two weeks 
Cya, Stewart
Smuggla huh? hmmm, i was off air when that debacle happened...
|
|
|
Club Member
Location:
sydney
Registered:
May 2002
|
|
|
Location:
On your mum!
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 10:49
|
|
oldcorollas - squeeze cast? I have not heard of this, though I readily admit that I am not a professor.
Perhaps a possibilty is that they may have been formed by "HIPPING"? this is the process used with formula 1 blocks and it stands for high pressure inert casting; they use this for formula one blocks because the block is a stressed part of the chassis.
This may be a similar process to that which the prof was talking about?
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 11:36
|
|
Hot Isostatic Press?
http://www.aiphip.com/WebPages/isostatic_overview. html
| Quote: |
Fatigue life is often better than achieved by any other processing method. HIPping can also be used to consolidate unusual powder combinations such as superconductors, ferrite’s, nuclear wastes, etc. It also is used to diffusion bond same and dissimilar materials that cannot be bonded otherwise. Many applications such as transparent ceramics cannot be manufactured any other way than HIPping.
|
a firend was using HIP to make 'functionally gradient materials" going from stainless steel to .. i think hydroxyapatite (bone like material) using HIP... interesting stuff.
HIP's usually used when forming items from powder.. ie "powder metallurgy" and is like sintering of ceramics, but under pressure. but can be used for casting consolidation.
the new BOSS 290 ford rods are sintered....
the pistons are definitely not HIP'd, as you would not see flow lines of any sort in the metal, as in the image above.
well Squeeze casting and semi-solid forming are not exactly common processes. i think you need to have excellent temperature control (within a few degrees) to keep the metal between the 'liquidus' and 'solidus', ie, it is a mush like half frozen cordial? the mush is then forced into a mold... under how much pressure depends on much much is solid and how much is liquid...
could result in flow lines, but the microstructure should still have casting artefacts, like dendritic structures (or remnants of these after heat treatment)
it is not an old techanology, but i'm finding out as much as i can... for a head start, there are some papers in one of the mid 90's "materials forum" conference publications...
in a weeks time
Cya, Stewart
[Updated on: Sun, 20 June 2004 11:50]
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 11:53
|
|
this is lovely http://www.minimania.com/MM/PISTONS___Whys_and_Whe refores_1206.htm
| Quote: |
PISTONS - Whys and Wherefores
This is another of those subjects abused for "bar stool b*llsh*t" one-upmanship. Ignorance is the main problem. Particularly as trying to get any really useful information out of the manufacturers concerned. Try phoning AE Hepolite technical. Getting hold of someone takes real perseverance. Having achieved that meagre goal, enquiring about piston specification gets those "lemon sucking" sorts of noises - anybody'd think you're asking for the Holy Grail! And they're not alone in this. And, as in numerous other subjects, the vendors/manufacturers will have you believe their product is the best, largely because they have a vested interest. So I'm going to cut through the techno-babble and tell you what's what.
Working Environment.
Piston, n. sliding cylinder fitting closely in tube and moving up and down in it, used in steam and internal combustion engine to impart motion. The pocket Oxford dictionary's description of the subject in hand. A bit minimalist, and not awe-inspiring. What a piston does, and the savage environment it does it in should be. Revered even.
For a start if it wasn't there, there'd be no drive whatsoever. It's responsible for drawing in and helping to contain the all important fuel/air mixture - the 'charge' - for the controlled explosion (combustion/'burn') that gives motion. The more combustion contained, the more power there'll be to provide motion.
The temperatures and loads it sees are extreme and practically instantaneous , going from fairly cool (incoming fuel/air mixture), to 'nuclear fusion' (combustion, measuring close to two thousand degrees C) within fractions of a second. That's 16.66 times a second at an average engine speed of 4,000rpm. Respect.
To add flavour, the piston top (crown) is running at massively different temperatures to the bottom (skirt), and the cylinder wall (bore) temperatures also vary. These differing temperatures cause varying amounts of expansion/distortion of both piston and bore. So now the piston has to vary it's own size to be able to cope with a 'tube' that's continually varying in dimensions to maintain a good 'fit'. Excessive clearance will allow the piston to wobble about causing premature wear of both piston and bore and reduce charge entrapment (i.e. blow-by will exist). Insufficient clearance will massively increase friction, leading to seizure of the piston in the cylinder. Disastrous.
The crown has to be immensely strong. The pressures it has to withstand compressing the charge, then enduring the rapid burn are enormous , we're talking well over ten thousand pounds per square inch. The clearance between piston and bore is sealed off using a set of metal rings (piston rings), carried by the piston. These rings are seated in grooves (ring lands) machined in the piston. To be effective, these are placed near the piston crown , right in the 'extreme environment' area , and fairly close together. The piston has to be strong enough to withstand the enormous pressures of combustion, and continual fretting of the rings as the piston hurtles up and down the bore. Then there's the extra shock loading imparted by any detonation (pinking) caused by incorrect ignition timing or poor fuel quality (octane rating) or simply weak/incorrect fuel/air mixture.
In short it has to be harder than Mike Tyson, yet as compliant as Olga Corbet. Tough act!
Material type.
Generally, various types of aluminium alloys are used to make pistons. The types used, and how, are what makes certain pistons superior to others. I said at the start that we're not going to get 'heavy' with the tech side - avoiding the likes of beryllium/aluminium and MMC ( Metal-Matrix Composite pistons) but cover the basic whys and wherefores that are the most relevant to making an educated decision about which is best for you.
FORGED , probably the most 'coveted' by the ill informed. Like 'billet' when referring to crankshafts. Forging pistons, apart from the following information, became the preferred option for race cars in the same way dog-box gearboxes did - it was a far cheaper and quicker process where limited production numbers were concerned and where technical changes were made frequently to make use of new knowledge/performance increases. One forging can be used to make several piston types for various different engines; each dimensional change can usually be catered for in the machining. With a cast piston - each new style generally means a new die - very expensive and time consuming.
Forging imparts a more consistent molecular structure within the alloy used, thus allowing thinner sections (less 'meat') to be employed to achieve its strength for minimal weight, although the finished article is generally softer than a cast equivalent. Strength for strength, a forged piston is generally lighter through extensive finish machining. Part of what makes them more expensive than cast items. Sounds the one to use, but...
Benefits : withstands higher compression ratios for less weight than cast variants. More tolerant of shock loading from incorrect ignition timing (detonation). Will absorb 'debris' (broken valves, spark plugs, etc.) without instantly disintegrating - basically more 'flexible', reducing total engine destruction. In which case they could be construed as being cheaper long term than cast pistons where racing is concerned.
Contras : alloy type used (most commonly RR58 developed by Rolls Royce in the early 1930s for the renowned Spitfire engine) expands more so needs greater running clearances; making them unstable and therefore noisy ('piston slap') until up to correct running temperature. This causes premature wear when used in 'street' engines. Difficult to use well; needs experience to obtain maximum performance. Over-rich mixtures creating bore washing accelerates wear. Ring lands wear quickly. Very expensive to manufacture. Basically they just won't do the mileage. Exactly what's needed in an out and out race engine where budget allows, but effectively useless in a road orientated or high mileage competition car.
CAST : the most prolific method of manufacture for a vast majority of pistons. Consequently far more development has gone into this method than any other , if for no other reason than its relative cheapness to manufacture. As the name suggests, they're made by pouring molten alloy into a mould. A major benefit being you can put the metal where you want it, reducing finish-machining costs. The biggest problem is maintaining correct and exacting temperatures when pouring the molten metal : this takes seriously expensive high-tech equipment, and huge experience. Getting it slightly wrong causes an inconsistent molecular structure that weakens the piston. Definitely not good! Just because they're cheaper doesn't mean to say they're not capable in a performance engine - modern products are a far cry from those made some 25-30 years ago. The specification, quality and consistency of the alloy used usually depend on piston application and size of manufacturer. So, where does that leave us with this?
Benefits : alloys and heat treatments used produces a much harder, stiffer piston. Very low expansion rates mean tighter tolerances, so vastly reduced noise and wear for street and high-mileage competition cars. Easier to use to good effect, maintains shape better and ring lands far more durable. Much cheaper to manufacture, therefore generally cheaper to buy.
Contras : generally doesn't tolerate incorrect ignition/fuelling too well leading to failure in abnormal circumstances. Doesn't absorb debris, causing fracturing and failure, and further possibly greater damage to other components. Higher strength types tend to be slightly heavier than forged equivalents, although latest technology has seen a dramatic improvement in material further improved with specific heat treatment processes to help reduce weight/strength differences.
SQUEEZE CAST : Developed by AE Hepolite, this combines all the plus points of both forging and casting pistons, whilst minimising the effect of the bad points. Just before the alloy poured into the mould solidifies totally, the casting's impacted. Simple to say, but complex to do accurately and consistently - the temperature of the alloy from liquid form to impact point has to be very carefully monitored. Again we're talking serious technology. Unfortunately AE have judged the process to be too costly to continue with - their continuous development programme enabling them to produce cast pistons of supreme quality, making squeeze casting redundant in their eyes.
Conclusion
Don't get mugged. Forged pistons are only necessary in serious, high rpm, race engines. Current hi-tech, hi-spec cast pistons are more than adequate for everything else, and are proving their worth in a vast majority of motorsport where mental compression ratios can't be used because of fuel limitations. Not to mention being loads cheaper.
|
[Updated on: Sun, 20 June 2004 12:00]
|
|
|
Location:
Brisbane / Gold Coast
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 13:29
|
|
I normally wouldn't touch this, but WHAT THE HECK! 
Picking a forged piston requires almost zero metalurgical knowledge.
As mentioned above, if the piston looks forged then there's an extremely good chance that it is. That means that if the inside of the piston has no casting marks and has a smooth shape (one that has no tight-radius edges & is shaped so that a 'slug' can move in & out to form the inner section) then it's a very good chance that it's forged.
Take a gander at the inside of this one, a TRD/Mahle forged Formula Atlantic piston
See how it can only be formed by a 'slug' pushing up into the underside of the piston, thus giving it it's shape. There are no casting marks, and if any metal is taken up between the gudgeon pin and the inner part of the dome it has to be machined/,illed out.
Anyway, suffice to say You-Know-Who is showing his usual complete ignorance again.
I guess this explains all ...
[Updated on: Sun, 20 June 2004 16:37]
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 20 June 2004 16:07
|
|
|
Bill, if you happen to come across any good forged pistons that have died, or any AE-hepolite 'squeeze-cast' pistons for minis... could put them in your lunchbox and donate them to the cause?
|
|
|
Location:
Adelaide
Registered:
October 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 21 June 2004 10:55
|
|
|
I thought the later 3ST-GTE had semi forged pistons and i was told it was when they just used one of the forging processes. Dunno. Maybe i should get a boosted motor first.
|
|
|
Location:
Adelaide, drift capital
Registered:
May 2004
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 21 June 2004 11:19
|
|
Has anyone got any pics of the top face of a 4AGZE piston? Could you please post it? I've just pulled the head off my GZE, and would like to compare the face of my pistons with another.
Cheers,
Joel
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
|
Location:
Adelaide, drift capital
Registered:
May 2004
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 21 June 2004 14:24
|
|
|
Thanks Stewart. Phew mine are ok. I never new that the face of GZE pistons (and I guess AGE pistons?) had those valve relief forms. At first site of my heavily carbon covered pistons, i thought that they may have somehow come in contact with the valves, creating the dents! Apon a recent closer expection, I realised that all the relief forms were identical (other than being deeper on intake side) of all four pistons, and in looking at the pics, they must be ok. I'll get some piccies of my pistons in my tired GZE.
|
|
|
Location:
Bundaberg, Qld.
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 21 June 2004 21:12
|
|
ahhh. my old piston, how i miss thee..
the other 3 from my old 4agze/4agte engine got used in a rather 'Macgiver' style 4agte engine rebuild on sunday arvo/night.
at least now my friend can drive home, it's amazing what 2nd hand rings, pistons and head gasket (gotta love Hylomar) can do when you want it.
|
|
|
Location:
On your mum!
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Tue, 22 June 2004 09:14
|
|
Thanks for the article Stewart. I am reasonably well versed in with piston manufacture, but it was good to read about AE Hepolite squeeze casting technique.
The author talks mostly about high RPM race engines needing forged items, but due to high boost turbo applications and the inevitable detonation, forged pistons do have a place in the daily driven market (either that or I am one of the ill informed that the author wrote of).
Note to self - HIP = high isoteric pressure
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 24 June 2004 11:34
|
|
well, after a number of emails from this guy, and trying to explain that there is no
| Quote: |
Well,basically a spectrum analysis is whats needed,I would expect these
lasers to offer the same sort of breakdown as a blood tester..in the way of
silicon,magnesium alumina ...a spectral read out of all constituents.This
sort of analysis leaves no need for human interpretation,or is this too CSI
Miami? ;o)
|
i tried to explain the analysis options available, but it seems this guy wants a machine that you put a smaple in and the "TRUTH" comes out with no human intervention (ie bias)
and this is his final say in the matter
| Quote: |
OK,so its all just your opinion of what you perceive.I dont need you to do any more tests for me because I know what they are.I think the volume of info i provided speaks for itself as to whether or not its rumour.
|
all he said was
| Quote: |
Hello,I'm not wanting to start a fight,but the ZE piston is not forged
there pressure cast.No OEM Toyota piston apart from genuine TRD are forged.There also coated with Teflon,not ceramic.I've personally coated 100K/W pistons with ceramic and there composites are completely different.You can see for yourself here: http://www.pbase.com/pentavalver
When I had the coating applied at HPC they queried if I wanted to coat the teflon with ceramic.
The main problem I see with your info is that there are now dogs sellingcast pistons at forged prices along with misinformation across the internet.
|
he persoanlly applied the coating when he got HPC to do it.. uh huh
| Quote: |
Stuart,thx for the reply.I know it sounds lame,but I have no "hard" evidence other than a rockwell hardness test carried out long ago.The finding was that the metal is not dense enough to be forged and they contained too high a level of silicon.
Along with both Bob Holden and John Falkner informing me of them being cast over a decade ago.I cant tell you of the process used,never been to the factory.
Yes,your right,the concept of the teflon was to prevent carbon build up,causing detonation/preignition,as the 1st gen ZE had no knock sensor control(remember this was probably 1975 knowledge).HPC knew of teflon being used in some Japanese OEM's and they told me the ceramic,though it cant be removed from metal it may not adhere to the teflon. Ofcourse,I knew more than they did and told them to apply it. I was a tad dissapointed when I could scrape the ceramic off with my finger nail. (
The teflon didnt work by the way...I pulled down an early ZE and it was caked in carbon.
The flow of grain is characteristic of any pressure type casting/forging
process,as you'd understand.Toda use a 3 tonne die to forg.Without something
of that nature to compare,it makes it a little 1 sided.
Tests to try? well,melting them down and testing for silicon content would
be a good one,this would determine if there hypo or hyper,along with a sheer
test,but its all 1 sided without a true forged item to compare to.
A couple of other points,if the ZE is a forged item,it would make it the only forged piston in Toyotas line up from the 2jz to turbo diesels,along with the price difference of $80-$100 V's TRD's $280 for a 13.4:1 item.Forging costs money.
And I will tell u this tidbit,an easy way to pick a casting from a forging is to turn the piston over,if its curved nicely around the gudgeon its pressure cast,if its machined flat under the gudgeon its been forged and machine finished.
Thx for the pic's by the way,the most interesting thing I found was even with the difference in C/R's the crown thickness was much the same,interesting.
|
and the clincher
| Quote: |
Stuart,the only reason I mailed u about this was that u were doing some real world analysis and your posts seemed quite cordial and I figured u might want some feedback on your efforts.
You can allready see the effect your info and standing has by the comments in the latest thread.People are just happy to believe what there told.
Do these machines u speak of actually process the input data or is it up to u to make an assumption on what you see?
|
well duh.....
i want feedback, but not for someone to tell me i'm wrong cos some guy down the pub told them something...
ps, if MODS want me to remove his comments, so be it... but i thought his original comments, which led to this thread being started, would be of general interest...
pps, comments about bill sherwood were removed
[Updated on: Thu, 01 July 2004 06:07]
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 24 June 2004 11:36
|
|
oh wait thers more
my comment | Quote: |
"well, these people respect my opinion, because they know my capabilities
and have faith in me... i am not afraid of proving myself wrong as long
as the scientific facts come out in the end"...
|
was replied to with this:| Quote: |
LoL,how humble of you.Thats all good and well,but,you can show 2 doctors a mole,1 will state its a mole,while the other may state its a deadly cancer :o/ while pathology equipment may deem it a pimple,if you see my point.
I dont see this as about being wrong or right,you had evidence that appeared to be of a certain origin based on your assumption and (rumour)my main concern is having that info on the board is doing more damage than good.I just think it should be removed until u have more evidential comparisons come to light.
|
i asked him for hard evidence and test results? nothing...nada.. squat...
[Updated on: Thu, 01 July 2004 06:08]
|
|
|
Location:
tallahassee FL usOFa
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 24 June 2004 14:22
|
|
thanks oldcorollas, but don't mud wrestle with a PIG. you'll only get dirty, and the PIG will enjoy it. 
|
|
|
Location:
Brisbane / Gold Coast
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 24 June 2004 20:31
|
|
| oldcorollas wrote on Thu, 24 June 2004 21:34 |
pps, comments about bill sherwood were removed
|
Ta for that Stuart.
As he is incapable of doing otherwise, they are all lies & fiction.
The truth here -> http://www.billzilla.org/smugstain.zip
|
|
|
Club Member
Location:
sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 24 June 2004 21:51
|
|
haha Stu was very light on the comments i can tell you... even my own personal banter with him on this topic was little more than a mud slinging match on both sides im embarrased to say 
but it was a little fun to have another dig at him
|
|
|
Toymods Social Secretary
Location:
Sydney
Registered:
July 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 24 June 2004 23:14
|
|
very diplomatically spoken stu.
You have proven that dispite anyone's attempts to try and resolve an unknown to determine the truth in the most open and scientific way, Mr Smuggs still refuses to play nice. One would almost think he is void of reason.
Anyway, lets just wait and see what Stu finds out. BTW Stu, if you need any help doing monkey work with those pistons, i might be able to give you a hand on weekends.
|
|
|
Banned by his request
Location:
moved to tamworth
Registered:
July 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Fri, 25 June 2004 00:45
|
|
stewart i put aside a couple of diffrent forgies for you. CP,srp,mahle,arias etc the CP's are out of our turbo motor you know the one. i have thousands of nascar forgies that are new ill try and find a broken set. they use metric second ring, they did this to get extra power with less fricton. are expenssive to put rings on and i mean very expensive so i might grab a few for you totest aswell. anything else CALLIES crank? they are so stong that when the dry sump pump belt broke it ran out of oil at 7500rpm and the crank bent the tunnel of bowtie block with billet caps, the crank is black from heat but straight amazing.
mick
p.s how you been bill? you seen the little sportsman that chris dowd did the 7age in? 200hp at the tires not bad for an atmo.
|
|
|
I supported Toymods
Location:
Perth, Western Australia
Registered:
December 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Fri, 25 June 2004 01:15
|
|
Priceless Bill, many thanks!
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Fri, 25 June 2004 13:09
|
|
i honetsly had no idea what had gone on before, but i have a pretty good idea now.. he even stirs shit on video forums and computer forums too!!!
he also posted to dorikaze
http://www.dorikaze.com/showthread.php?t=1276
i feel compelled to reply so that others are not so misinformed..
i have not found the GZE pistons to be forged, but i have observed flow lines characteristic of forging, but after speaking to my professors at my university, i think that 'squeeze-casting/semi-solid forming/thixotropic casting' are all possibilities, but they all have characteristic microstructures and should be fairly easy to tell the difference.
i have observed a 'coating' on the order of 15 microns thick. it has an undulating surface which is similar to that formed from plasma spraying, but i have not analysed the chemistry or crystallography of the coating yet.
it should be trivial to do with a low-angle XRD machine, a RAMAN spectroscopy machine, and EDS analysis in an SEM.
if the need arises, i do have the option of some late night ion milling to make a TEM sample, which which absolutely determine the crystal structure if it is indeed crystalline.. unfortunately this requires around 10-15 hours of electron microscope beam time......
thanks Karl, i'll be cutting it up on monday
should be able to run some tests this week.
AWESOME , thanks heaps Mick. it will be very very interesting to compare the differences. hopefully i should be able to pop down on sunday after lunch.. what time is the last race??
i now feel like a wasted a good 15 minutes replying to his emails, trying to find out more information as i am seriously interested in finding out more, only to have him declare that he knows and doesn't need me to do any testing for HIM!!!
does anyone kow what he meant when he said
| Quote: |
CybaSmuggla
Member
Registered: Nov 2002
Location:
Posts: 57
03-06-2003 10:57 AM .
Thx for the kind words SKD,Its a Toyota Levin/Trueno origin "Blacktop" 4AGE 1.6lt 20 valve.
5 valves per cylinder design by Yamaha,has variable valve timing,and quadthrottles.
Its bottom end was destroyed in an accident in Japan,holes in the block,I got a hold of it and rebuilt it,ported...balanced,the usual garb,the pics are from a video of its rebuild,some of its componentry is appealing even to the layman.I'll be adding to it,so I can let you know if you like.
Theres some 16V pics also.All the work is my own.Cheers.
http://www.pbase.com/pentavalver/100kw_16v
|
http://forum.digital-digest.com/archive/topic/1728 0-1.html
he fixed a block with holes in it?? whu??
anyways, for better or wrose, the pistons will still be analysed
Cya, Stewart
|
|
|
Location:
Carlingford, Sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sat, 26 June 2004 02:26
|
|
| Bill Sherwood wrote on Fri, 25 June 2004 06:31 |
Ta for that Stuart.
As he is incapable of doing otherwise, they are all lies & fiction.
The truth here -> http://www.billzilla.org/smugstain.zip
|
hahahahaahahaaa
what a tool
has he any idea
thanks for that Bill, must have been pita dealing with him all the time
|
|
|
I supported Toymods
Location:
Epping, Sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sat, 26 June 2004 04:03
|
|
so, in conclusion, smuggla is a keyboard warrior?
haven't read through it all, idiocy is amusing at first, then it just becomes frustrating
intersting how he doesn't understand that being an international pilot requires you to be out of the country for significant periods 
people like that, who just never give in, just change their position in an argument to what they think is right, frustrate me. I like nothing better than proving myself right, but if someone can show me I'm wrong I'm the first to admit it and learn from it!
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sat, 26 June 2004 08:39
|
|
Draven, i agree totally. if i'm wrong, i admit it. it is in my professional and academic interests to report my results fully, and it is also ethically required of a professional engineer.
here is his last email to me.
| Quote: |
Date: Fri, 1 Jan 1999 00:42:08 +1000
From: PPC
Subject: Re: ZE pistons.
Get fucked idiot,nice post,damn I had u wrong...whats the difference in eutectics ??? you dont know shit Uni boy,taking my email and editing it the same way the others do...you had to ask me "IS SILICON REALLY THAT IMPORTANT?"
YOU DUMB SCAMMY FUCK,you havent got a fukin clue,if you cant dazzle with brilliance,baffle with bullshit right?? yep...just like the rest.
You got all the equipment but cant prove a fukin thing.
PUT IT IN WRITING BITCH.BET YOU WONT.Captain phd.
|
to which i replied
| Quote: |
well it seems i was both wrong and right about you.
eutectic occurs at a singular composition. a eutectic is formed from
liquid phase directly to solid phase. ie liquidus and solidus are at same
temperature at that composition.
i know how important silicon is.
and what do you bet that i won't put it in writing.
whatever you do bet, i would like it to be given to an independent third
party, such as a law firm or accounting firm.... heck even the police or a
JP would be fine with me but i don't think they would agree..
i have no intention of not doing the analysis. your comments have not
swayed me..
all i wanted from you was for you to share the information you had with
me, hoping that we could come to a better understanding of these pistons.
it seems i have given you a lot more time and understanding than many
other people have, and i thought you would appreciate it?
please just share your information. if you don't you are no better than
everyone else who is sputing shit about GZE pistons without a leg to stand
on.. both those that do and don't think they are cast/forged/semi-forged..
all i want is the test reports and your sources.
thanks in advance.
Cya, Stewart
|
i believe i have been more than patient with him.
part of his previous email was| Quote: |
I chose to discuss this with you as I expected you to be professional,it now
appears you want to throw things off track and avoid the issue,which I geuss
is to be expected.
I'm not a metallurgist,engineer,or mechanic,but 1 does not need to be to
understand fundamentals of any of them.I'm not 1 to just believe anothers
OPINION because of some letters after there name,if you think u can stand
over me with that 1,I'll call your bluff.Besides that,your still pretty wet
behind the ears in your industry,so what does your opinion mean in the real
world?
|
what i should have said to him was next time he gets on a plane, he better thank god that my research has been accurate
Cya, Stewart
[Updated on: Thu, 01 July 2004 06:10]
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sat, 26 June 2004 08:43
|
|
and he should thank me when one of his relatives gets a cochlear implant, or he uses one of the next generation bubble jets, or he gets a metal implant in his body
ahhh.. i love consulting work, and not just for the $$
|
|
|
Location:
Carlingford, Sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sat, 26 June 2004 16:00
|
|
very well handled stu (i would want to kick his arse by now)
damn ive been reading thru all the crap bill has been tru with this guy...
|
|
|
Location:
Brisbane
Registered:
August 2003
|
|
|
Location:
On your mum!
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 27 June 2004 06:59
|
|
I had a similar experience as Greg while reading through that (I still haven't finished) I started out amused, became incredulous, and by the feeler guages I was outright frustrated.
Star engine builder? 
Good work Stewart
|
|
|
Location:
Melbourne
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 27 June 2004 07:22
|
|
|
are thay available in 2mm oversize?
|
|
|
Club Member
Location:
sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 27 June 2004 08:36
|
|
|
I believe someones working on a full draft of the last few days email activities .. should be a good read by all accounts , hopefully theyll have it up in the next few days
|
|
|
Toymods Social Secretary
Location:
Sydney
Registered:
July 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 27 June 2004 12:12
|
|
nice one mike... but whilst we all wait... something for old time's sake....
|
|
|
Location:
Carlingford, Sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Sun, 27 June 2004 13:43
|
|
|
haha love it
|
|
|
I supported Toymods
Location:
melbourne.victoria.austra...
Registered:
June 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 09:35
|
|
pwned.
visit from the karma bus about due.
|
|
|
I supported Toymods
Toymods Club Secretary
Location:
Sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 10:10
|
|
| THE WITZL wrote on Sun, 27 June 2004 22:12 |
nice one mike... but whilst we all wait... something for old time's sake....
|
I know I shouldn't laugh, but.....
|
|
|
I supported Toymods
Location:
Perth, WA
Registered:
May 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 10:16
|
|
|
so if they are in fact forged then there wouldn't be any point buying some aftermarket pistons?
|
|
|
Location:
Melbourne
Registered:
August 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 10:47
|
|
| ae95 wrote on Mon, 28 June 2004 20:16 |
so if they are in fact forged then there wouldn't be any point buying some aftermarket pistons?
|
| Quote: |
PISTONS - Whys and Wherefores
This is another of those subjects abused for "bar stool b*llsh*t" one-upmanship. Ignorance is the main problem. Particularly as trying to get any really useful information out of the manufacturers concerned. Try phoning AE Hepolite technical. Getting hold of someone takes real perseverance. Having achieved that meagre goal, enquiring about piston specification gets those "lemon sucking" sorts of noises - anybody'd think you're asking for the Holy Grail! And they're not alone in this. And, as in numerous other subjects, the vendors/manufacturers will have you believe their product is the best, largely because they have a vested interest. So I'm going to cut through the techno-babble and tell you what's what.
Working Environment.
Piston, n. sliding cylinder fitting closely in tube and moving up and down in it, used in steam and internal combustion engine to impart motion. The pocket Oxford dictionary's description of the subject in hand. A bit minimalist, and not awe-inspiring. What a piston does, and the savage environment it does it in should be. Revered even.
For a start if it wasn't there, there'd be no drive whatsoever. It's responsible for drawing in and helping to contain the all important fuel/air mixture - the 'charge' - for the controlled explosion (combustion/'burn') that gives motion. The more combustion contained, the more power there'll be to provide motion.
The temperatures and loads it sees are extreme and practically instantaneous , going from fairly cool (incoming fuel/air mixture), to 'nuclear fusion' (combustion, measuring close to two thousand degrees C) within fractions of a second. That's 16.66 times a second at an average engine speed of 4,000rpm. Respect.
To add flavour, the piston top (crown) is running at massively different temperatures to the bottom (skirt), and the cylinder wall (bore) temperatures also vary. These differing temperatures cause varying amounts of expansion/distortion of both piston and bore. So now the piston has to vary it's own size to be able to cope with a 'tube' that's continually varying in dimensions to maintain a good 'fit'. Excessive clearance will allow the piston to wobble about causing premature wear of both piston and bore and reduce charge entrapment (i.e. blow-by will exist). Insufficient clearance will massively increase friction, leading to seizure of the piston in the cylinder. Disastrous.
The crown has to be immensely strong. The pressures it has to withstand compressing the charge, then enduring the rapid burn are enormous , we're talking well over ten thousand pounds per square inch. The clearance between piston and bore is sealed off using a set of metal rings (piston rings), carried by the piston. These rings are seated in grooves (ring lands) machined in the piston. To be effective, these are placed near the piston crown , right in the 'extreme environment' area , and fairly close together. The piston has to be strong enough to withstand the enormous pressures of combustion, and continual fretting of the rings as the piston hurtles up and down the bore. Then there's the extra shock loading imparted by any detonation (pinking) caused by incorrect ignition timing or poor fuel quality (octane rating) or simply weak/incorrect fuel/air mixture.
In short it has to be harder than Mike Tyson, yet as compliant as Olga Corbet. Tough act!
Material type.
Generally, various types of aluminium alloys are used to make pistons. The types used, and how, are what makes certain pistons superior to others. I said at the start that we're not going to get 'heavy' with the tech side - avoiding the likes of beryllium/aluminium and MMC ( Metal-Matrix Composite pistons) but cover the basic whys and wherefores that are the most relevant to making an educated decision about which is best for you.
FORGED , probably the most 'coveted' by the ill informed. Like 'billet' when referring to crankshafts. Forging pistons, apart from the following information, became the preferred option for race cars in the same way dog-box gearboxes did - it was a far cheaper and quicker process where limited production numbers were concerned and where technical changes were made frequently to make use of new knowledge/performance increases. One forging can be used to make several piston types for various different engines; each dimensional change can usually be catered for in the machining. With a cast piston - each new style generally means a new die - very expensive and time consuming.
Forging imparts a more consistent molecular structure within the alloy used, thus allowing thinner sections (less 'meat') to be employed to achieve its strength for minimal weight, although the finished article is generally softer than a cast equivalent. Strength for strength, a forged piston is generally lighter through extensive finish machining. Part of what makes them more expensive than cast items. Sounds the one to use, but...
Benefits : withstands higher compression ratios for less weight than cast variants. More tolerant of shock loading from incorrect ignition timing (detonation). Will absorb 'debris' (broken valves, spark plugs, etc.) without instantly disintegrating - basically more 'flexible', reducing total engine destruction. In which case they could be construed as being cheaper long term than cast pistons where racing is concerned.
Contras : alloy type used (most commonly RR58 developed by Rolls Royce in the early 1930s for the renowned Spitfire engine) expands more so needs greater running clearances; making them unstable and therefore noisy ('piston slap') until up to correct running temperature. This causes premature wear when used in 'street' engines. Difficult to use well; needs experience to obtain maximum performance. Over-rich mixtures creating bore washing accelerates wear. Ring lands wear quickly. Very expensive to manufacture. Basically they just won't do the mileage. Exactly what's needed in an out and out race engine where budget allows, but effectively useless in a road orientated or high mileage competition car.
CAST : the most prolific method of manufacture for a vast majority of pistons. Consequently far more development has gone into this method than any other , if for no other reason than its relative cheapness to manufacture. As the name suggests, they're made by pouring molten alloy into a mould. A major benefit being you can put the metal where you want it, reducing finish-machining costs. The biggest problem is maintaining correct and exacting temperatures when pouring the molten metal : this takes seriously expensive high-tech equipment, and huge experience. Getting it slightly wrong causes an inconsistent molecular structure that weakens the piston. Definitely not good! Just because they're cheaper doesn't mean to say they're not capable in a performance engine - modern products are a far cry from those made some 25-30 years ago. The specification, quality and consistency of the alloy used usually depend on piston application and size of manufacturer. So, where does that leave us with this?
Benefits : alloys and heat treatments used produces a much harder, stiffer piston. Very low expansion rates mean tighter tolerances, so vastly reduced noise and wear for street and high-mileage competition cars. Easier to use to good effect, maintains shape better and ring lands far more durable. Much cheaper to manufacture, therefore generally cheaper to buy.
Contras : generally doesn't tolerate incorrect ignition/fuelling too well leading to failure in abnormal circumstances. Doesn't absorb debris, causing fracturing and failure, and further possibly greater damage to other components. Higher strength types tend to be slightly heavier than forged equivalents, although latest technology has seen a dramatic improvement in material further improved with specific heat treatment processes to help reduce weight/strength differences.
SQUEEZE CAST : Developed by AE Hepolite, this combines all the plus points of both forging and casting pistons, whilst minimising the effect of the bad points. Just before the alloy poured into the mould solidifies totally, the casting's impacted. Simple to say, but complex to do accurately and consistently - the temperature of the alloy from liquid form to impact point has to be very carefully monitored. Again we're talking serious technology. Unfortunately AE have judged the process to be too costly to continue with - their continuous development programme enabling them to produce cast pistons of supreme quality, making squeeze casting redundant in their eyes.
Conclusion
Don't get mugged. Forged pistons are only necessary in serious, high rpm, race engines. Current hi-tech, hi-spec cast pistons are more than adequate for everything else, and are proving their worth in a vast majority of motorsport where mental compression ratios can't be used because of fuel limitations. Not to mention being loads cheaper.
|
Did you read this?
|
|
|
I supported Toymods
Location:
Perth, WA
Registered:
May 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 11:02
|
|
|
yes, but i thought oldcorollas is doing more tests to once and for all prove beyond reasonable doubt that they are in fact forged.
|
|
|
Location:
1st street on the right
Registered:
November 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 12:32
|
|
| Quote: |
what i should have said to him was next time he gets on a plane, he better thank god that my research has been accurate
Cya, Stewart
|
Next time he gets on a plane he'd better hope bill's not flying it!
|
|
|
Location:
Montrose, VIC
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 13:18
|
|
I'm definately interested to know what these pistons are made of, but when my gze is going again soon, well that'll be the real test for me. If it can take what I'm gonna give it, then they're bloody strong. If not, I'll have to use something else! 
|
|
|
Location:
Carlingford, Sydney
Registered:
May 2002
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Mon, 28 June 2004 13:23
|
|
|
haha aint that the truth
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 01 July 2004 06:17
|
|
| allencr wrote on Fri, 25 June 2004 00:22 |
thanks oldcorollas, but don't mud wrestle with a PIG. you'll only get dirty, and the PIG will enjoy it.
|
apparently i have been affected by his dirt already..
Due to threats of legal action, i have removed references to his name and email address from this thread.
| Quote: |
Actually,I think its time I went to the CIB about you and your buddies harassment.Do you know its illegal to use a telecommunications device to harass some1? Posting emails is akin to recording conversations.
Why would I tell you what I know and who I know,I've educated u enuff.look at how u have acted.
Stuart Ford right? I'll give u 24 hours to remove ur crap about me on that forum,then I'll play it Bill Sherwoods way and go to the CIB,u want the hassle?
|
so what the heck
i have removed the crap (ie name and email address), and just left what he actually said...
a full transcript of emails between us is available to all curious parties and law enforcement officers alike.
fwiw, he claims to have just found out the exact process used to make these pistons... but of course, will not share because "he has taught me enough already"... funny how since having claimed since 92 to know how they were made, he suddenly finds out exactly what the process is after abusing me about it.
i honestly don't get it.
anyone have mates in the QLD police force?
Cya, Stewart
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 01 July 2004 06:21
|
|
and on a brighter note,
i conducted some X-ray diffraction experiments on the coating yesterday, and found excellent spectra for aluminium and silicon (no surprises there, the spectra are likely to be from the underlying alloy surface, not the coating itself).
i will be putting the coating sample on the low-angle XRD next week hopefully, and have negotiated to have it tested by RAMAN spectroscopy also...
for the coating sample being tested, i used the largest flat area on the piston, the intake valve flycut.
Cya, Stewart
[Updated on: Thu, 01 July 2004 06:22]
|
|
|
Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
|
|
Re: 4A-GZE pistons, the TRUTH!
|
Thu, 01 July 2004 06:50
|
|
| ae95 wrote on Mon, 28 June 2004 21:02 |
yes, but i thought oldcorollas is doing more tests to once and for all prove beyond reasonable doubt that they are in fact forged.
|
i am doing tests to try and prove beyond reasonable doubt, "HOW THE PISTONS WERE MADE"
looking at a microstructure is a bit like digging up fossils. the metallurgical process that occur during the manufacture of a metal item can be very complex, and trying to backtrack is not easy.
we all know these pistons are GOOD.
i want to find out more about them and WHY they are good, and also to dispel the urban myths with a little scientific evidence.
i was surprised by the number of people who emailed me saying they know for sure what they are. but none have provided evidence to substantiate their claims.
i will provide evidence
Cya, Stewart
|
|
|
Location:
Sydney
Registered:
March 2003
|
|
|
| Current Time:
Sun Nov 17 08:31:55 UTC 2024 |
Total time taken to generate the page: 0.010561943054199 seconds |
