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Location:
Rockhampton, Queensland
Registered:
August 2004
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how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 06:08
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just a question to give me some idea as to how big is "too" big for my intended application.
i am looking at using a turbo that has the following specs on my 4a-gte.
TURBINE A/R .84
COMPRESSOR A/R RATIO .70
is anyone using the same or bigger and if so, what is the response like? when does boost come on? etc?
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Location:
wollongong NSW
Registered:
August 2003
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 06:18
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WaLLy has the following on his 4agte ae86:
HKS GT2535 - 340 PS Output
COMPRESSOR:
-Wheel- 56 Trim - 51.6 Inducer / 69.0 Major
-Housing- 60 Inlet / 50 Outlet - 0.60 A/R
TURBINE:
-Wheel- 76 Trim - 53.8 Major / 47.0 Exducer
-Housing- GT25/T3 inlets / Outlet specs:
Internal GT25 outlet; 0.64, 0.86 A/R
runs about 10psi, thats what boost controller is set at.
doesnt seem to laggy from the times ive been in there.
but he might say otherwise.
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 07:47
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thanks for the info mate!
anybody else????
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Location:
parra
Registered:
June 2003
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Location:
Sydney
Registered:
September 2004
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 10:01
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I think the general consensus will be that a 0.64 rear AR is just about right for a 4agte. I'm pretty certain ke282tg runs a 0.48 rear housing and says there is basically zero lag.
I'll now be running a hks gt2540 with a 0.6 front and 0.64 rear housing.
Eddie.
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Location:
parra
Registered:
June 2003
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 10:15
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DiZ's TD04L spools up very fast.
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 12:38
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thanks for the input guys, i really appreciate it. As a general concensus would a gte spool a 0.84 exhaust housing? i dont mind about lag, i just want the power at the end. Does anyone know of anywhere/anyone using a turbo on a gte with a exhaust housing bigger than the 0.6X ones?
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Location:
Brisbane
Registered:
February 2003
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 13:29
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I'm running a td05h-16g that with the 7cm2 exhaust housing. It's a bit laggy but streetable and not excessive.
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Location:
Toronto, Downtown
Registered:
September 2004
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 13:47
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im using a gt2535 with the sames specs as wally
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Location:
Inside a giant turbo (syd...
Registered:
June 2002
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 14:34
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gt2535, There is hardly any lag at all.. on 10psi or 18psi. This is with a 2.5 inch exhaust tho, so when ive got the 3 inch on there with 22psi ill let you know.
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Location:
Newcastle
Registered:
June 2002
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 14:37
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Spanktown Wins!
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 21:47
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Spanktown - what size is your exhaust housing on your 2535?
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Location:
wollongong NSW
Registered:
August 2003
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 22:08
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instead of making another thread ill just add another question in here.
the people that are running the gt2535, what is a safe amount of boost that can be run on a gze block? without things going bad.
asking because wally has the boost controller in his and the previous owner had it set at 10psi, and curious as to what it could run.
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 22:11
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what is the exhaust A/R on a GT2535? and does anyone use bigger?
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Location:
Toronto, Downtown
Registered:
September 2004
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Re: how big is your turbo on your 4a-gte?
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Tue, 18 October 2005 23:57
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| WiLo wrote on Wed, 19 October 2005 08:08 |
instead of making another thread ill just add another question in here.
the people that are running the gt2535, what is a safe amount of boost that can be run on a gze block? without things going bad.
asking because wally has the boost controller in his and the previous owner had it set at 10psi, and curious as to what it could run.
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ahhh as much as the gt2535 can push im hoping mine will push about 22psi. The issue with the 4agze is not the block pistons rods crank etc... its having the support systems for 22psi like fuel system aftermarket computer oil cooler etc etc
A stock gze should support 200rwkw's no problems given the right support systems
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Location:
wollongong NSW
Registered:
August 2003
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Re: how big is your turbo on your 4a-gte?
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Wed, 19 October 2005 00:27
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hmmm, think i might have the increase the boost on WaLLy and hope he doesnt see me do it 
should be able to support a bit of an increase i think, has LTX8,oil cooler, and fuel system is alright i think.
end of off topic discussion 
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Location:
Toronto, Downtown
Registered:
September 2004
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Re: how big is your turbo on your 4a-gte?
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Wed, 19 October 2005 00:38
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you will need to get it tuned for the increased boost pressure
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: how big is your turbo on your 4a-gte?
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Wed, 19 October 2005 13:42
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Top thread!
I'm using an HKS GT2510 which is .60 front & .64 rear, and up to 24-25psi. It seems a bit laggy, but then again I usually drive around on 18psi, so 4 grand is when it really starts to pull hard. Running 12-15 psi there is very little lag, but then after running 25 it makes 12 feel N/A! 
Mine's put up with 25psi on a rebuilt standard bottom end, HKS head gasket and 9:1 C/R, and Performance Springs http://www.toymods.org.au/sponsors.php#17 valve springs being the only internal changes, externally it has all the other bits necessary (obviously). Now consider that's with a faily small turbo in the scheme of things (aftermarket & HKS-wise) a bigger more efficient at that airflow turbo would make that boost with a fair bit less effort, so 22psi should be no sweat for a GT2535, or a standard GZE bottom end.
BTW, that 25psi (plus my recently installed diff & LSD) scored me a 12.6@108mph tonight at the drags. Yay!
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Wed, 19 October 2005 13:49
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thanks for your info BigWorm!
i just hope i can spool mine up! going to run 20psi! so hopefully it will get there.
I am using a gze bottom end, forged pistons, with stock crank and rods, acl bearings all round and arp rod bolts, arp head stud kit, and arp flywheel bolts.
Since your stock setup handled it, i hope mine will too. If i can spool it that is?
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I supported Toymods
Location:
Frankston, Victoria
Registered:
April 2004
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Re: how big is your turbo on your 4a-gte?
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Thu, 20 October 2005 06:59
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I plan to build a 4A-GTE soon, just a matter of time and money.
With all of those internal upgrades I wouldn't be surprised if you could rev the thing all the way to 9000RPM, so I wouldn't be worrying about how late the boost comes on, if you changed gears at 9000RPM the next gear would probably start at 4000RPM anyway . It would just be a matter of initial take-off.
Just checked out your site and my god you're dedicated to your car hahah, $13k!! Good shit man
Kev.
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Location:
u.s.a. south
Registered:
April 2004
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Re: how big is your turbo on your 4a-gte?
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Thu, 20 October 2005 19:52
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BigWorm
why did you change only the valvesprings ?
Because of boost pressure... or oe were tired ?
bigport cams ?
what do you rev to ?
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Banned by his request
Location:
moved to tamworth
Registered:
July 2002
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Re: how big is your turbo on your 4a-gte?
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Thu, 20 October 2005 22:01
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| Phrostbyte wrote on Thu, 20 October 2005 16:59 |
I plan to build a 4A-GTE soon, just a matter of time and money.
With all of those internal upgrades I wouldn't be surprised if you could rev the thing all the way to 9000RPM, so I wouldn't be worrying about how late the boost comes on, if you changed gears at 9000RPM the next gear would probably start at 4000RPM anyway . It would just be a matter of initial take-off.
Just checked out your site and my god you're dedicated to your car hahah, $13k!! Good shit man
Kev.
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why rev to 9000 when you have boost?engine want last long with high boost and high revs.7500rpm is plenty with boost,unless you want to kill it quick.
gt2535 or small trim 2540 is perfect turbo for 4ag.
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Registered:
September 2005
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Re: how big is your turbo on your 4a-gte?
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Thu, 20 October 2005 23:14
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i have a 20V with LTX8 microtech, 1Jz injectors and a IHI RHF5 turbo which i have no idea what its off. the Spec of it says VN14. Its a T25 flange and about the same size as a T25G physically, however i dont know what the AR ratios are but this turbo is very veyr laggy on my 20v, Since im using my car for drift i have found it to be far too laggy to be of much use through multiple corners where i have to back off.
top end is awesome tho, when it comes on boost it just PULLS hard, makes 150 rwkw's on 10psi. stock internals also.
i am swapping my turbo for a T25g which should make the same power but spool up earlier.
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: how big is your turbo on your 4a-gte?
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Fri, 21 October 2005 09:32
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Quest, the valve spring upgrade was mainly due to the planned high levels of boost, as you probably know for every pound of boost you run, your valve springs are effectively 1 pound softer (that's a fairly rough/cautious calculation). Also seeing as the engine was being rebuilt and we have a spring manufacturer as a sponsor I figured best not to rely on the 20 year old stockers.
Yeah I'm running the bigport cams with stock cam gears & rev limiter is set at 7000rpm. I was suprised Dave at SAS set the limiter so low, but seeing as peak power is made at 6000rpm and revs is what wears out engines I figured it's a pretty good idea to leave it there.
If/when I get cams I imagine this might change a bit....
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Location:
Canberra
Registered:
May 2002
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Banned by his request
Location:
moved to tamworth
Registered:
July 2002
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Re: how big is your turbo on your 4a-gte?
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Fri, 21 October 2005 11:06
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| BigWorm wrote on Fri, 21 October 2005 19:32 |
Quest, the valve spring upgrade was mainly due to the planned high levels of boost, as you probably know for every pound of boost you run, your valve springs are effectively 1 pound softer (that's a fairly rough/cautious calculation). Also seeing as the engine was being rebuilt and we have a spring manufacturer as a sponsor I figured best not to rely on the 20 year old stockers.
Yeah I'm running the bigport cams with stock cam gears & rev limiter is set at 7000rpm. I was suprised Dave at SAS set the limiter so low, but seeing as peak power is made at 6000rpm and revs is what wears out engines I figured it's a pretty good idea to leave it there.
If/when I get cams I imagine this might change a bit....
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but in overhead valve engines the seat pressure is very soft compared to pushriod engines,which is a great thing.imagine having to run over 180 on the seat.
mick
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 03:06
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many thanks for the replies guys, i am definately upgrading my valve springs. I had an idea that it was a good idea beforehand, now i am starting to think it is a necessity.
Still cant decide whether to go with a 0.63 AR smaller turbo or a 0.84 Exhaust AR larger turbo though. Might be a case of trial and error i think...
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 04:51
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| kingmick wrote on Fri, 21 October 2005 21:06 |
| BigWorm wrote on Fri, 21 October 2005 19:32 |
Quest, the valve spring upgrade was mainly due to the planned high levels of boost, as you probably know for every pound of boost you run, your valve springs are effectively 1 pound softer (that's a fairly rough/cautious calculation). Also seeing as the engine was being rebuilt and we have a spring manufacturer as a sponsor I figured best not to rely on the 20 year old stockers.
Yeah I'm running the bigport cams with stock cam gears & rev limiter is set at 7000rpm. I was suprised Dave at SAS set the limiter so low, but seeing as peak power is made at 6000rpm and revs is what wears out engines I figured it's a pretty good idea to leave it there.
If/when I get cams I imagine this might change a bit....
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but in overhead valve engines the seat pressure is very soft compared to pushriod engines,which is a great thing.imagine having to run over 180 on the seat.
mick
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I'm sorry, what was your point?
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Banned by his request
Location:
moved to tamworth
Registered:
July 2002
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 06:33
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lol missed a whole sentence!point was dont go to high on seat pressure on overhead valve as it doest need it at all,keep it under 55lbs or your wasting power.
mick
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Banned by his request
Location:
moved to tamworth
Registered:
July 2002
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 06:41
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dave would have set the revs low because it dosnt need the revs with the extra boost,the lower you can keep the revs the longer the engine will last,if its a new engine you want it to loosen up abit aswell, as its not a race motor running big clearances.
mick
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Location:
u.s.a. south
Registered:
April 2004
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 11:45
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On the springs, makes sense. cool
TE72_Turbo
What symptoms pointed you to 'tired valvesprings' ? Did the power fall off sharply.... valvetrain got noisy in high rpms ?
what 267 cams do you run ? Did you notice a considerable gain ?
Did you have to change lifters or reshim ?
I'm not looking to make a hi revver. There is enough rpm range for a decent powerband for a street car imo. I'm curious about what a cam and valvegear costs vs the performance yield.
My plan is to throw ~20-24psi of "small" t3/t4 at a stock 4age. Looking for ~320whp and ~300 ft-lbs tq. Should give a hard accelerating midrange, as opposed to a more peaky tq curve and extended rpm range.
Next project is a ca18 sprinter, that I'm sure can go silly quick with the same approach. Perhaps +40whp/tq more. Got ~$600usd into that drivetrain and swaps r ez 4 me, so its kinda hard to justify throwing money at 4ag valvegear mods.
A turbo 7ag might make an interesting comparison.
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Location:
Canberra
Registered:
May 2002
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 12:03
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| Quote: |
Still cant decide whether to go with a 0.63 AR smaller turbo or a 0.84 Exhaust AR larger turbo though. Might be a case of trial and error i think...
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I'd prefer to keep a smaller (0.6x) A/R, and rather fit an external wastegate to get the extra exhaust flow, whilst retaining response.
| Quote: |
TE72_Turbo
What symptoms pointed you to 'tired valvesprings' ? Did the power fall off sharply.... valvetrain got noisy in high rpms ?
what 267 cams do you run ? Did you notice a considerable gain ?
Did you have to change lifters or reshim ?
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Was like a light ignition miss, started off initially like a soft rev cut (just a hesitation really), but as the springs got worse, it would eventually sound like it was popping into the inlet manifold & also backfire out the exhuast, and basically didn't want to rev through it. It was still running stock cams back then.
The 267 cams are a wade billet grind, with only slightly more lift than factory spec. Lifters remained standard, just shims were changed to suit the clearances required.
I actually tried Wade's 280 degree cams first with almost 8.5mm lift, but despite their initial advice, they cams actually lifted one side of the shim about 1.5mm off the bucket/lifter when turned over by hand! Thank god I didnt start it up and give it a rev before noticing. Now Wade don't recommend those cams without a "shim under" conversion kit
Cheers
Phil
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 14:24
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| DanielGVisser wrote on Tue, 18 October 2005 16:08 |
just a question to give me some idea as to how big is "too" big for my intended application.
i am looking at using a turbo that has the following specs on my 4a-gte.
TURBINE A/R .84
COMPRESSOR A/R RATIO .70
is anyone using the same or bigger and if so, what is the response like? when does boost come on? etc?
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http://forums.toymods.org.au/index.php?t=msg&t h=84482&start=0&rid=1976&S=ef281373242 c3f4e7eda7afbffc938dc
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 14:46
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as for seat pressures.
stock 4AG seat pressure is what? 35lbs?
intake valve area is 1.06 square inches... sayy roughly 1sq" taking away the valve stem area (if we want to get exact.. 6mm valve stem = 0.0558 sq", 29.5mm valve = 1.0594sq", so..= 1.0036sq" minus the area shrouded by valve seats)
so yeah, Joels rough calc is dead on the money 
1pound boost = 1pound heavier seat pressure.. for a 29.5mm dameter valve.
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Location:
Toronto, Downtown
Registered:
September 2004
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Re: how big is your turbo on your 4a-gte?
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Sat, 22 October 2005 17:37
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| DanielGVisser wrote on Sat, 22 October 2005 13:06 |
Still cant decide whether to go with a 0.63 AR smaller turbo or a 0.84 Exhaust AR larger turbo though. Might be a case of trial and error i think...
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this is a fwd car is it???
in which case too much power might not be ideal depending on your application.
If it were me id aim to use the smaller of the exhaust housings to minimise lag so that the cars not a dog when your driving it on the street.
just my $0.02
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Sun, 23 October 2005 01:32
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thanks guys, decided to stick with a 0.6X housing and using an external wastegate.
Many thanks for all your help!
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I supported Toymods
Location:
melbourne
Registered:
June 2002
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Re: how big is your turbo on your 4a-gte?
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Sun, 23 October 2005 01:45
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If you can, do not route the wastegate pipe back in to the exhauist pipe, if you kee it seperate you will get better boost control.
this means you will have to muffle it seperately, as screamer pipes are teh ghey.
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Location:
Rockhampton, Queensland
Registered:
August 2004
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Re: how big is your turbo on your 4a-gte?
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Sun, 23 October 2005 06:53
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no worries, that was my original intention anywho. Thanks for the confirmation though! Much appreciated!
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Registered:
September 2005
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Re: how big is your turbo on your 4a-gte?
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Sun, 23 October 2005 07:17
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you can re route the wastegate exhaust back into the main exhaust system further down the line, not too close to the back of the turbo.
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: how big is your turbo on your 4a-gte?
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Mon, 24 October 2005 15:21
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| TE72_Turbo wrote |
I actually tried Wade's 280 degree cams first with almost 8.5mm lift, but despite their initial advice, they cams actually lifted one side of the shim about 1.5mm off the bucket/lifter when turned over by hand! Thank god I didnt start it up and give it a rev before noticing. Now Wade don't recommend those cams without a "shim under" conversion kit
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Interesting, I've been looking into cam profiles & lifts (only half-arsedly so far) and came across the following website which lists cams for standard bucket & shims & cams for shimless or shim under buckets, and the standard shim cams went up to .493" (just under 10mm) with 300+* of duration!
http://www.camshaftshop.com/camsha fts/view/27/toyota-camshaft/
It makes you wonder just how many of these cams these guys have sold...
I've almost pretty much decided to go with some of the Toyota 1sz-fe shimless buckets so I don't have to be too restrained when it comes to cam selection. Then I just need to work out how big I want to go. 
Whadaya reckon Phil? I'm also interested to see what the 2510 can handle, currently power drops off very gradually up to revlimit, so it doesn't look to be struggling. I s'pose it'll come down to how mental I go when I choose a profile, but, if I find it is getting a bit strenuous for the old girl, then dammit I just might have to get something a little bigger! 
| oldcorollas wrote |
as for seat pressures.
stock 4AG seat pressure is what? 35lbs?
intake valve area is 1.06 square inches... sayy roughly 1sq" taking away the valve stem area (if we want to get exact.. 6mm valve stem = 0.0558 sq", 29.5mm valve = 1.0594sq", so..= 1.0036sq" minus the area shrouded by valve seats)
so yeah, Joels rough calc is dead on the money Wink
1pound boost = 1pound heavier seat pressure.. for a 29.5mm dameter valve.
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Sweet!
That does get me a bit worried though, the springs I used have 50lb seat pressure, so during my occasional () 25 pounds of boost my 50lb valve springs are now 25lb springs! I guess that's just another very good reason to rev limit it to 7000rpm, rather than it's standard 7700rpm redline; anyone know when standard rev limiters kicked in?
So when I do get stuck into cams & buckets etc I'm going to have to shim them up to increase the seat pressure, to at least 60lb I reckon, which depending on what lift cams I choose (maybe around 9mm?) will leave the springs about 1.125mm away from binding. It's a bit of a fine balance between spring seat pressure & cam lift (and boost!).
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Banned by his request
Location:
moved to tamworth
Registered:
July 2002
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Re: how big is your turbo on your 4a-gte?
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Mon, 24 October 2005 21:44
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i use 3sg buckets in 4ag's.
mick
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Banned by his request
Location:
moved to tamworth
Registered:
July 2002
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Re: how big is your turbo on your 4a-gte?
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Mon, 24 October 2005 21:53
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in race motor i use 48 pounds on the seat{ohv}with 30psi and making 800hp from 2.3litres at 30psi and 8000rpm{this engine has also done a few dyno runs at 45psi and 11500rpm and it made huge power} around the circuit for 4 years and has been threw 2 sets of springs .you dont need over that you need to look at spring quality and setup etc.
mick
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Location:
Canberra
Registered:
May 2002
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Re: how big is your turbo on your 4a-gte?
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Tue, 25 October 2005 13:07
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bigworm: I believe those 1sz-fe shimless buckets are $28 each trade price from toyota. Not the cheapest exercise... besides, are you sure you want to go wild enough on the cam profile that you need the shimless kit? If you plan to keep your rev limit low, then its a bit contrary to fitting large cams which might kill your bottom end significantly 
That NZ cam site is interesting, pretty big claims for their standard shim setups!
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: how big is your turbo on your 4a-gte?
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Tue, 25 October 2005 13:12
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ahh, but high lift cams don't always mean overlap.... high ramp rates at lower rpm will smack the valves open, probably with similar forces to lower lift, longer duration cams at much higher rpm...
i like the ide of high lift, low overlap
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Toymods Board Member
I supported Toymods
Location:
Turramurra, Sydney.
Registered:
May 2002
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Re: how big is your turbo on your 4a-gte?
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Tue, 25 October 2005 17:47
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Phil, yeah it's not cheap, but hey it's a whole lot cheaper than any of the aftermarket kits, & seeing as wade cams are so cheap it's a good chance to put the money I'm saving straight back into the motor.
And the lowish rev limit wasn't & isn't planned, that's just how it worked out. I do feel a bit guilty though restricting a 4AGE to only 7 grand, and like you say I don't want to totally destroy the low down torque, but hey with 1600cc, usually 18psi and a 3.7:1 diff ratio, anything below 3500-4000 fells pretty weak anyway, and it's also reaching the stage where the celica really needs to be a weekend car....
I need to sit down & do a bit/lot of research into cams & effects of lift vs. duration, because like Stew I've been thinking that for F/I cam upgrades a bigger increase in lift & smaller increase in duration might be the way to go. I figure for N/A, not so big lift will keep velocity up and increased duration will allow more air in (plus the overlap will help pull more air through), but for F/I you really want the opposite; a mild(ish) increase in duration to avoid overlap & a good increase in lift to let it flow more.
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Registered:
October 2005
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Re: how big is your turbo on your 4a-gte?
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Tue, 25 October 2005 22:19
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Out of curiosity, how well does the stock afm gze computer handle turboing?
I've heard it runs out at 15psi with the SC, I'd guess turbo would be the same. Does it have issues having the sc unplugged?
Did toyota make stock 4agte's? How much boost can their computers handle?
My SC is running about 10psi, it's got a nevo pulley. I'm thinking it's a tad worn out if that's all it can manage, so turbo is sounding tempting - especially if it's basically a a bolt on for 15psi.
When you all talk about turbo part numbers, I have nfi what they mean, so is there a specific engine you're all nicking them off?
ca18det? sr20det?
cheers
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Location:
Toronto, Downtown
Registered:
September 2004
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Location:
u.s.a. south
Registered:
April 2004
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Re: how big is your turbo on your 4a-gte?
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Thu, 27 October 2005 01:20
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The only camshaft I would ever consider is the exact cam that show definite and measurable gains over stock, from a credible source.
Seen FAR too many 'junk' grinds pushed off on customers. Seems like most cam grinders have a generic "one size fits none" spec on file, that they ship out to the consumer to 'try', with no R&D whatsoever with that particular motor. Very common.
Look at the Wade 280 cam/shim problem TE72 mentioned, for example.
I bought a cam years ago that did absolutely nothing vs stock. Swapped directly for another brand (as advised by a very experienced 3tc builder) and the car never pulled so hard. No other changes. Really opened my eyes to what a HUGE difference a *correctly designed/ground* camshaft makes. I'll settle for nothing less after that.
I wouldn't weigh too much on cam "specs". They're pretty useless imo.
There are tons of threads on the net littered with testimonials of poor performing cams. For instance, HKS cams are the benchmark for mitsu turbo 4s due to their consistent dyno AND dragstrip gains. A few other cam makers were called upon to provide a lower priced alternative. Took about three different cam companies later to finally succeed. Even with HKS cams *in hand* the "lesser" cam grinders still couldn't match it!
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Location:
Toronto, Downtown
Registered:
September 2004
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Re: how big is your turbo on your 4a-gte?
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Thu, 27 October 2005 01:56
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yes imho cashaft and turbo selection can make or break an engine package in terms of driveability and performance
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