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Location:
Newcastle
Registered:
May 2002
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Location:
Newcastle
Registered:
May 2002
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Re: Attn: bluewire.
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Sun, 23 June 2002 06:18
 
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bump!!!
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Location:
Sydney
Registered:
May 2002
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Re: Attn: bluewire.
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Sun, 23 June 2002 09:17
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try PMing him
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Location:
New Zealand
Registered:
May 2002
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Re: Attn: bluewire.
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Sun, 23 June 2002 11:10
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have you read that article by Tim Frost on S/Cing a 2TGEU?
My friend Marks (KE20 + 3SGTE + IRS + soarer front end) reckons that this is one idea for 2TGZEU.
3SGTE AFM - flows more air.
bigger injectors - too make if for more airflow for same door open amounts.
Standard ecu - it senses airflow, not boost.
Now... perhaps the AFM could be tightend so that it fully opens under 7psi or so..... rather then as soon as any boost is present.. as the NA will never suck over atmospheric, so factor afm is set to be full at 0psi i imagine.
Just rambling.
Karl
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Location:
Adelaide, South Oz
Registered:
May 2002
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Location:
Adelaide, South Oz
Registered:
May 2002
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Re: Attn: bluewire.
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Sun, 23 June 2002 15:16
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Hey Karl
Where do i find the article by Tim Frost on supercharging a 2TGEU? 
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Location:
Melbourne
Registered:
June 2002
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Re: Attn: bluewire.
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Sun, 23 June 2002 15:47
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Hey Bluewire,
when you say 'rebuild the engine to give the best psi' what exactly do you mean?
The boost you run (psi-pounds per square inch, a measure of pressure) is determined by the charger - in this case the size of the pully wheel on the supercharger (smaller wheel = more boost).
When you say rebuild the engine to suit i assume you mean rebuild it with lower compression to suit higher boost. You can quite happily supercharge a stock NA engine but you are limited to the maximum amount of boost you can run happily. By lowering the compression and strengthening you allow more boost to be run without breaking stuff!
More boost means higher inlet temps and greater risk of knocking. It also means greater risk of breaking other stuff (bottom ends etc) simply by making more power... 
There are also a number of different superchargers which have different characteristics, eg positive displacement (like on a 4AGZE and i assume most Toyota's) or centrifugal etc.
You can adjust the boost through fiddling with the pulleys - just ask any 4AGZE owner who has simply changed the supercharger pulley to boost their engines up to 14psi!
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Location:
Melbourne
Registered:
June 2002
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Re: Attn: bluewire.
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Sun, 23 June 2002 15:55
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Sorry, me again...
But Karl, you have confused me too!
What is the 'AFM' ? I assumed it was an Air Flow Meter but then you started talking about it opening and closing!
Also, when you say injectors to make for more airflow do you mean fuel injectors - cause they only inject fuel and make no difference to airflow - although a boosted engine will use more fuel and will need bigger injectors to deliver it.
Usually on a boosted engine you will use a MAP (Manifold Air Pressure) sensor but Air Flow Meters still work fine.
Just confused by the acronyms! Sorry!
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Location:
New Zealand
Registered:
May 2002
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Re: Attn: bluewire.
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Sun, 23 June 2002 20:34
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AFM = airflow meter.
But I think they measure this by how much the flap is open.
Now, pressure builds as soon as you have a restriction, so... at 1psi the AFM will be wide open, whearas in NA, this probably wouldn't happen until 6000rpm or so.
Soooo, if you can make the AFM stiffer, so that it only opens full at 7psi or so.... then you'll have some degree in variability of fuel in relation to boost.
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I am talking about fuel injectors.
Basically, relating to the AFM door opening early would tell the ECU to give full fuel..... way over rich for only 1psi or so.
Secondly, if you run a bigger AFM, I think you will get the same reading at the computer.... but naturally the door is much larger so much more air (volume) is flowing.
To make up for the increase in air volume, bigger injectors will be needed all round.
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Hope this clears my thoughts up
Karl
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Location:
Melbourne
Registered:
June 2002
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Re: Attn: bluewire.
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Mon, 24 June 2002 00:39
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Ok, that has helped alot.
I assumed you were talking about a hotwire type AFM not a potentiometer flap type.
Everything you say is right, but i don't think it will work.
The problem is that it is a very haphazard way of controlling the fuel. It rely's on you getting AFM and injector sizes PERFECTLY matched to the boost and engine characteristics - very unlikely!
More likely than not you will end up with an engine that runs very badly if at all.
You need much finer control over the whole rev range as the load, boost and temperatures change. This means an aftermarket fuel controller. It will make thing easy to adjust help liberate a few ore kW! You will be dicing with death (of the engine) if you run a turbo/supercharger with a stock NA ECU.
Hope that helps!
Beena.
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Location:
New Zealand
Registered:
May 2002
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Re: Attn: bluewire.
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Mon, 24 June 2002 04:26
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okay, yes it will require exact sizing....... but with 365cc injectors on 4AGZE, I'm assuming something of similar rate will suit my car.
Also, the s/c is linear in rate, so as long as the afm opens more with boost, then it should be fine.
Of course, this would guzzle the gas as the magnetic clutch setup wouldn't be running.
Karl
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Location:
Melbourne
Registered:
June 2002
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Re: Attn: bluewire.
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Mon, 24 June 2002 04:40
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Ok yes, the S/C is linear in rate (assuming a +ve disp. charger) but the fuel map may not reflect this. There are many things than can cause an engine to run rich or lean and simply giving more fuel with more boost makes for a very risky proposal!
You will also have to retard your ignition to prevent detonation., and provide some sort of temperature compensation. It is because of things like this that most of the turbo conversions you see run an aftermarket computer.
It will also be very expensive to find the right sizings (if you could...) as it would mean sitting on a dyno and changing injectors and AFM's to get the right combination!
If i were you i would abandon the idea and just get an aftermarket ECU. It will be far cheaper, run better, make more power and use less fuel!
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Location:
Newcastle
Registered:
May 2002
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Location:
New Zealand
Registered:
May 2002
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Re: Attn: bluewire.
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Mon, 24 June 2002 12:37
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okay, for ignition, i was thinking about the programmable electronic ignition kit from Jaycar.
But, i do understand that there are many, many,,,,,, many factors in working out the correct AF ratio.
Karl
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Location:
Melbourne
Registered:
June 2002
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Re: Attn: bluewire.
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Mon, 24 June 2002 14:03
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I am a BIG fan of Jaycar and use them alot for bits and pieces so i would expect their ignition kit to work well.
I am still worried about your fuel delivery though...
In my personal opinion you should still go for a cheapish aftermarket fuel control ecu. Most of these have a built in MAP sensor so you can get rid of the AFM completely and upgrade your injectors with something bigger and cheap.
This way you can borrow a EGO sensor or let a joint with a dyno tune it and end up with a good, fast, reliable engine. With the added bonus that if you decide to change anything (engine, SC etc) you can remap it to suit.
Also things like idle control and cold start assist will work better.
The other reason I am doubtful is that I hav never seen it done before, usually a good sign that it is too hard/expensive or just does not work. Although i spend most of my time around rotary's so maybe someone else has seen it work...
I just don't want to see you spend lots of money and time working on something that ends up a dud. The way i see it, any extra money now will be worth it in the long run.
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Location:
New Zealand
Registered:
May 2002
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Re: Attn: bluewire.
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Mon, 24 June 2002 20:18
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sure.
My friend had a SC12 setup on his 5K using the standard 2TGEU computer and apparently it ran mint. I haven't had a chance to ask him about it.
I'd rather do stuff with std ecu if possible, but if that's not possible, an aftermarket ecu would have to be used, if only for fuel. Wolf2D or something
Thanks for your thoughts.
Karl
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Location:
Newcastle
Registered:
May 2002
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re.
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Wed, 26 June 2002 12:26
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i went and got a price on a SC14 supercharger today $395 from all jap which is cheaper than i thought nit would be, but their intercoolers looked like shit and they want from $150 for one with bent fins and all that crap. just have to work out fuelling systems and that sorta stuff.
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