Ok so I'm waiting on fall to put it on my car.. in AZ there's no chance of summer fun lol

It will be a completely stock b20. From head to block. But before I can finish it. I had a few questions.. I'll be running a custom forward facing t4 manifold with twin mvr's, and a gt4088. And I know a gt40 is big, but it has a .81 hotside. So hypothetically speaking it should spool up a "little" better over the bigger 1.14 hotside. This will be a full on street car, with some track time of course.. and before you say my turbo is to big. Let me beat you to it. I know!!! BUT I want to try it for myself... car will be on e85 with id1000's and s300... looking to make anything over 300whp for now with room to make more after tax season lol
So the list...

Custom T4 forward facing manifold
Gt4088 (.81 hotside)
2 MVR's
2.5 ic piping, with hks balck edition bov
Basic intercooler for the time being
Id1000's
S300




So my first questions is, should I run a 3.5in down pipe, or 4in or what? Which would benefit me more with spool time

Second, is what oil restrictor should I have on it? Some say I don't need it on a journal bearing turbo. Some say.to get a .60 or .65..

Third, what should be my "expected" spool time?

Any and all suggestions are welcome..

 

Unfortunately this setup sounds like a dog of a car. Guessing stock cams and stock port p 75 head? I don't think a stock b20 can even turn the rpm needed to think about spooling a t4 frame gt40. You should re evaluate how you're spending money this way isn't worth the hassle or aggrovation when granny in her Toyota terel beats you to 60mph.

300 hp is easily attainable with anything from a t25 frame to t3/31 framed turbo's that will be much more responsive and the power band will be much more usable. 3076r, silver surfer, hx35 or even a 2876 is even a possibility for 300hp.

 

co-sign
the turbo is way to big and by the time that turbo builds enough boost for some use youll have to shift gears. bigger isnt always better

 

I appreciate the quick response guys. But I kindda knew that aeady about the turbo. That's why I wanted to try it. Given this will be a semi built motor come tax season. But for now imma try to rock it.. I wasn't really looking for low end power.. more of top end if you know what I mean. According to the maps on the gt40 it should "start" spooling around 5500 6k. But won't really hurt to try it for myself. Now if it really is that bad after everything I'll just get a hx35. But for now, I would rather try it, seeing that I already have it. BUT if it comes to it, and I did use a t3 platform, would an adapter from t4 to t3 hurt anything?

 

Your stock rods will only rev to 7200rpm reliably with 84mm pistons on it. So you might be coming across the boost threshold and making miniscule manifold pressure at 55-6000rpm, full boost soon after so you are looking at a 1,000 rpm wide power band. When you shift it will fall out of boost and right onto its face.

then grannys gonna dump it from D4, down to #2 gear in the tercel crack vvti and walk on ya.

Youre setting yourself up for dissapointment, its not a "will it work" type deal, its been done and its a terrible setup for what youre trying to accomplish

 

Yep, you realistically won't be able to push enough air to make that turbo work for you. It's even almost too big for a pure drag setup, and that's saying something. You'll end up a lot happier with a GT(X)30 or 32 series.

 

agree with all, way to big turbo.

you can use this turbo only with b18 head, b18 ecu-wirings and 9000 rpm limiter.

the .81 hotside has little to do when you have such a huge wheel.