Some Q about my Twin Turbo setup before I go

[mshawari1]

Here we go … Some suggestion will help ….

- Twin turbo (Garrett) out of 2000 cc engine. 2 inch inlet and 0.36 A/R with internal wastage .
- Stock internals and ECU
- Stock injector but I will find some way to rise the fuel pressure.
- No intercooler … maybe later on
- No BOV

My goal is 290 rwhp ~ 350 rwhp at about 8 psi. >>>>>>>>

Q:
Is 0.36 A/R ok ?? or it will make restriction … I can replace it with 0.48 A/R in the exhaust side.
Do the IC will help with big numbers ??
How can I keep the boost at 8 psi ?? and how I can rise it up

Thanks in advance
​

 

[cribbj]

If you're not going to intercool, then you should consider a Methanol/Water injection system to cool the charge air. This will also help you with the additional BTU's (fuel) that you'll need. The 1UZ's are already high compression engines, so any boosting that you're doing, particularly in such a hot climate as yours is asking for trouble.

No BOV is again asking for problems, especially when you've been at WOT and you suddenly let off, and there's nowhere for all that boosted air to go. It's not good for the turbo's.

The 0.36 A/R is really small, but if you've already experienced this turbo on a 2.0 litre motor, then putting two of them on the 4.0 litre Lexus motor should give you about the same response. Try it, then if you have problems, go to the larger housing. One thing is for sure, you won't have any turbo lag!

You'll need to control/limit your boost with a wastegate on each turbo.

It seems to me that you're going to go through a lot of trouble and expense to twin turbo this motor for not a lot of boost. Why don't you consider a small supercharger instead? It will be less work than a twin turbo installation because you won't need to touch your exhaust system, and for only 8 psi or so, you probably won't even need to change your belt drive system. Higher boost than this might require a wider belt, or a dedicated S/C drive.

You'd still want to put a M/W system on it, and a bypass valve (the S/C's version of a BOV), however many of the Eaton S/C's already come with an internal bypass valve. The M90 Eaton has been a popular SC for low boost applications - have a search on this site using M90 as the key word and you'll find some nice installations.

 

[mshawari1]

cribbj

Thanks for your reply … BUT
I will not go with SC because I don't have one and it is expensive for me.
The turbo have wastage already. But the engine which I take turbo from don't have BOV.
And I agree with you and will install IC. ​

 

[mshawari1]

If I install water injector it will replace the intercooler >> No need for IC ???

What is the suggested cc/min for that water injector under 100 PSI​

 

[4000GT]

I dont know of any .36 twin turbo 2.0 turbos. Are you sure they are not .63? As found on the VG30? Tell me the motor its off and I will tell you what you have. If looking for Garrett 2.0 single turbo turbos... then go for the GTIR or S15 T28's. If anything if is good then TD05 of the EVO are nice.

The turbo on a 2.0 motor will be internaly gated. Almost certain if Japanese. That can control boost at a set level, get a controller otherwise.

I am doing a WI setup, but an IC is by far the cheapest and more reliable, so just get an IC.

The cc/min of water in the injection should be a percentage of fuel as a ratio, some suggest 10-25%. You need pulse width modulation ideally to map it.

Oh and get a valve else you will get compressor surge...

 

[mshawari1]

I am sure it is 0.36 >> take a look ( it is strange to be like that but I don't know why ?? )
Also here is the seconded turbine with 0.48​

 

[Pro]

looks like a SAAB or Volvo turbo - but has a T3 flange?

 

[mshawari1]

hey I can't see the pic ..... the 0.36 for Nissan L20-T , The 0.48 for Toyota MU-TE all ~ 1985