20V vs 4AGZE + Turbo

[Pure-SX]

My car has currently got a silvertop 20V sitting under the bonnet, I was wondering about the most cost effective way of turboing it, I know that people will say that the 4AGZE is a better engine due to its internals etc. but I am wondering if it would be more cost effective to keep the 20V, get manifold made up, new ecu intercooler etc and only run low boost 5-8psi. I am not looking for massive amounts of power just enough to keep me happy. Later on I would more then probably add forged internals etc.

[Ben Wilson]

It should work fine with low boost.

You'll need to build up (at least) a custom plenum as the factory one won't handle boost. Apparently some model 3S-GTE has side feed injectors so they would be an easy upgrade.

Freal4mr2 has run a NA 16v decompressed by fitting two head gaskets and it lasted a fair while...

[Pure-SX]

How would one build a custom plenum, talk to a workshop? possible to get premade ones or shall i just talk to some of the guys that have previously turbo'd a 20V?

[Ben Wilson]

It depends on how good you are with a welder

It shouldn't be that big a job for a fabricator to knock up a simple one. I'd personally ditch the quads and go for a single TB on the plenum inlet. That will make the thing a lot easier to tune, apparenlty some wierd stuff happens as the car comes on boost with turbos and quads. It also gives you a lot less potential leakage points (can you tell I'm planning something similar?)

[Pure-SX]

awww but i love my quad throttles, :'(.
hrmmm, if i was to keep quads what path would i go down,
i will be postin my ride in members rides section jkust gotta take some piccies AE82 corolla sedan

[Ben Wilson]

They can still work, but the tuning might be a little more complex (and it might get a bit tighter for space).

All you need for a cheap plenum is 4 bits of 2" exhaust pipe going into some sort of box (4" pipe is nice, but not cheap) and an inlet pipe. Just weld some flanges to the bottom of the stubs so they bolt onto the TBs and you're laughing..

[Pure-SX]

If i was to make a custom plenum, It would be able to keep quad throttles? and less prone to leak?

[progkamol]

My friend from US was talking about turbo kit for 20V engine before. I believe, and quite sure, that he said it was for a 20V black top engine. Don't believe me 100% coz thats just what I've heard. There a quite a few US boys using 20V blacktop turbo. My friend lives in Virginia (not sure address) and he knows some one who sells turbo kit (don't know how much it costs) The guy name is Emm I believe. I can give you the e-mail if u want and u can contact and find out more with him. Will PM e-mail address to you.

[takai]

If i was to make a custom plenum, It would be able to keep quad throttles? and less prone to leak?

Yeah custom plenums are quite easy, and if welded properly wont leak like a sieve either.
Still reasonably easy to tune as well

[hybridaddy]

For starters dont use exhaust pipe,use aluminium and definately keep the quad throttles.
Set up properly it will be the same as an rb26

you want something like this

[Ben Wilson]

They must like spending extra money - Why on earth would you join a plenum to the TBs using hoses and clamps? All you need to do is weld flanges to the end of the pipes (it will suck to do some of the bolts up, but you won't need to do it very often)...

[hybridaddy]

Also to get around any vacuum related tuning issues use a balance pipe setup for the map sensor.
To do this you simply tap 4x 1/4" brass fittings on the inlet manifold behind each throttle plate but before the injector.Connect them all together and there is your map signal

[hybridaddy]

They must like spending extra money - Why on earth would you join a plenum to the TBs using hoses and clamps? All you need to do is weld flanges to the end of the pipes (it will suck to do some of the bolts up, but you won't need to do it very often)...

doing it like that guy did would make it easy to fit up and eliminates any possibility of poor alignment.
i know i would rather it be setup like that if i was making it,and for the cost of $30worth of hose and $20 worth of clamps it would also be cheaper than making flanges and welding them on

[Pure-SX]

I have justr had an idea it may be due to my lack of sleep as of late, what would happen if i was to supercharge a 20V with 4agze bits??? would that be easier than turboin a 20V?

[hybridaddy]

I have justr had an idea it may be due to my lack of sleep as of late, what would happen if i was to supercharge a 20V with 4agze bits??? would that be easier than turboin a 20V?

lack of sleep rofl!
even if it was easier you would be stuck with a (no offence to anyone) crappy supercharged setup with no room for upgrades in the future and disapointing performance.

while some people might complain about turbo lag there is nothing worse than the feeling of an engine running out of puff up top.