turbo sizing

[dnalunchie]

For that sorta power (200hp) I wouldn't even bother with GZE internals. I'd leave it high comp and run an S13 SR T25G or a S15 BB T28 at most. TD05 is nice but that's really a 300+ turbo so response will never be as good as it could be on a 200hp setup. I'm a strong believer in running the smallest turbo that will get to your power goals without choking the engine up top and having as high comp as you can get away with for response and fuel economy.

+1

The T25 runs out of puff on a 2ltr but should "just" be able to reach the top end of a 4age and should come on very quick. Would be able to get 200-220 atw easy with that and as you said could run higher comp

[lorolla24]

I Have been running ST with 8.9:1 ze pistons and 550cc injectors. The rest is standard with a Gt28BB .64 hot .48 cold,@ 13psi and 200kw atw. Old link ecu.
Real nice to drive, smooth power all the way though.
In my Ke35.

Would go with a slightly bigger turbo next time. .60 cold.

[STR]

I'm watching this topic with interest, 'cos I'm in much the same boat. Running 4AGTE (ZE originally) and I had a VF38 making about 180hp on 12psi and 240 on 18psi, until the VF shat itself. I'm on the hunt for a replacement, but am weary of VFs after a bit of research. Leaning towards a TD05H at the moment, but still researching as I don't really want/need any more power.

[stacy]

Well this is all awesome, it seems my power goal is conservative i thought id start with a goal of 200 hp but there is no question that we all ways want more which is why i went with gze pistons as eventually id like more power and by all accounts it seems that its possible thanks for all the input guys its awesome, now which injectors?.

[Dell'Orto]

3SGTE 440s will easily do 200hp

[dnalunchie]

3SGTE 440s will easily do 200hp

would the larger 550/540's (memory failing) from the later gen 3sgte's also fit? Just might be similar money but with more future proofing

[lorolla24]

Yep, that's what I got. Found a set off TM for $180.
Need to use ballest resistors with them on the link ecu. Not the 440's

[Dell'Orto]

3SGTE 440s will easily do 200hp

would the larger 550/540's (memory failing) from the later gen 3sgte's also fit? Just might be similar money but with more future proofing

THey do, but aren't as common and are dearer

[evil_si]

Ive always used 550cc rx7 injectors

[Bazda]

For standard replacement turbos a TD05 twin scroll would be the pick.

Make a proper twin scroll manifold to suit.

[thegreatestben]

Ive always used 550cc rx7 injectors

When I had mine tuned (had those injectors) Andre at STM mentioned while they will do they job they are pretty old now and while they'll throw as much fuel in as you need, newer/better injectors will do a much better job of economy and give a better spectrum of tuning.

I always thought mine was overly thirsty even when trying an economy run week.

[stacy]

Well it looks like I'm gonna have to double my hp target I've lined up some Subaru injectors, any thoughts on these?

[~SlideWays~]

Well it looks like I'm gonna have to double my hp target I've lined up some Subaru injectors, any thoughts on these?

My thoughts are that they are from a Subaru. Other than that they could be any cc rating really.

[mega4a]

i made 240 hp on a gt2860r with 4afe head spools up quick full boost by 3500rpm great turbo if you go Nissan turbo though make sure you get the steel shaft ones not ceramic.

[loose_unit]

Evo 510cc and 560cc injectors are a much better option than the RX7 injectors. Much better spray pattern, the RX7 ones pretty much pour the fuel in. Seem to be able to pick them up pretty cheap now too. At 311whp on my 5e the 560's were still only at low 80% duty cycle.

[gt4dude]

gt2860rs I've found to be slightly on the small side for a 3s-g so I'd imagine would be perfect on a 4a-g or even a 7a-g

either way I was still able to max out 540cc injectors with one..

[STR]

Bit of a thread dredge, but seems an appropriate place to ask:

TD05H-20G on a 16v 4AGZE. Too big for a 1600?
Ideally would use a 16G but have been offered a 20G at a good price

[Crucible]

^ I would say probably getting a little big. Imo for a street car a 16g is pretty much as big as you want to go.

Depends what your using the car for of course.

[mjrstar]

Interesting, I would think a later model twin scroll td05hr 20g turbo could be a good match if selecting a small genuine evo exhaust housing. My 20g'd evo 9 turbo makes 18psi at 3000rpm so would imagine a 4age should have good boost at less than 4000rpm?

[matt dunn]

Dont under-estimate how much effect compression ratio has on turbo lag.

I changed from about 8.0:1 to 8.9:1 and with the same turbo and manifolds got boost 1000rpm earlier,
Which on a street car is a big difference in driveability.