Gt35R Twin Scroll build....

[PhantomK]

I am looking to build a twinscroll set-up up based around a GT35R Twinscroll turbo. The turbo is basically new and was given to me for nothing pretty much. And I was wondering what kind of set-up I can run in order to make it the most responsive. I'M not looking for power, just response....and yes i know I can have better response with a 3071R or a 2871r but sorry I have this.....

Anyway, I'm a total newb when it comes to engine building and really would like to have some incite on this. So my questions are:

Recommended Compression ratio:

Pistons:
Rods:
Crank:
Proper bore to support that size turbo:

necessary headwork inorder to flow enough to support the turbo and etc.

If I had to shoot for an HP # I'd say 400whp.

And the motor is a S13 Redtop SR20DET that currently has 555cc injectors, intake full exhaust, and etc. I plan on buying a seperate motor and building that one in the mean time.

Flame on.....(ps....im really not that new, I've been around, and I've searched. Not many 240s run a 35R so this is why I made this thread)

I'd actually like to hear from steve shadows or smelly240 on this one.

[S14_Kouki]

location DUB C do you live in wesley chapel

[GSXRJJordan]

To be honest, a GT35 is never going to have "stoplight to stoplight" response like a 2871 or 3071 on an SR20. It will however be nice above 4500RPMs or so.

You should sell it, and start with something smaller ~

[PhantomK]

Nah i live in the same town as Bam Margera and Ryan dunn. West Chester, Pa. And GSXRJJordan. I don't expect amazing response out of this thing. It was given to me and I'd like to build a motor around it and then step down to a 30R later on down the line.

In addition to this, I have been kicking around the idea of selling my SR20DET set up and going RB25DET with this turbo.......I'm not to well versed on the swap into an S14 chassis. Also, I am not to well versed on what the engine itself can take before having to go forged internals. I'm just looking for a streetable and reliable set-up. I am having a feeling though that 6 cyl will get me there better than 4 cyl.

[GSXRJJordan]

Originally Posted by PhantomK

In addition to this, I have been kicking around the idea of selling my SR20DET set up and going RB25DET with this turbo.......I'm not to well versed on the swap into an S14 chassis. Also, I am not to well versed on what the engine itself can take before having to go forged internals. I'm just looking for a streetable and reliable set-up. I am having a feeling though that 6 cyl will get me there better than 4 cyl.

Now you're talking! I recently did the swap myself, and have done a few for other people.

The twin-scroll GT35 is the ideal turbo for the RB25/26, in my opinion. A healthy RB25 can take at least 400whp in stock trim (I've seen it with a GT3076 @ 18psi on pump gas), more info on exact setups for stock internals can be found on Skylines Australia - the manifold is going to be the most expensive part of that setup, probably cost almost as much as the motorset lol.

Shoot me a PM/email if you have questions about the swap, I can help ya - I do swap wiring, too!

[PhantomK]

Well then you are the man to talk to. My overall goal is balance for this S14. It's been through hell and I want to show off that is a great platform for a budget sportscar. I say budget because of the vehicles I seek to match and exceed performance wise.

Since obviously my SR isn't going to be capable of this. My next step is finding reasonably priced RB motorsets.

[Ali 556]

dunno,

so you will pay 4-5K$ just for the 0.5L increase... The 0.5 will get you less lag by 400-500 rpm at best...Full race mani + back door fmic etc etc you will get what 900rpm less lag at best...keep in mind that you will pay AT LEAST 3-5K$ for the mani and other stuff,

If you ask me...either go KA rebuild and turbo it...BRAD D on KA-t.org made 630WHP threw C4 AUTO trany on his S14, Some random dude made 655whp threw Z32 trans...

OR

Swap a 2JZ-GTE granted you will pay lots and lots of $$$ to do it...but the 2JZ-GTE is bullet proof and will make 700-800 WHP on S T O C K internals....and it's a 3.0L engine and can be stroked to 3.4L (will cost you around 8K for the stroker kit and you can made up to 1400whp with it)

YouTube - Cody Phillips 1399rwhp 6 speed Supra

Your call

[GSXRJJordan]

Originally Posted by Ali 556

dunno,

so you will pay 4-5K$ just for the 0.5L increase... The 0.5 will get you less lag by 400-500 rpm at best...Full race mani + back door fmic etc etc you will get what 900rpm less lag at best...keep in mind that you will pay AT LEAST 3-5K$ for the mani and other stuff,

1) He's selling his SR20 to purchase the RB25. Net loss (read: cost of the upgrade) is less than $1000.

2) The difference in spool with a GT35R will be greater than 1000RPM, from the dyno's I've seen (to be sure you'd have to have identical designs, etc) - SR's spooling at 4500-5000 and RB's spooling between 3000-3500. The point is, that's a very important 1000rpm on the street.

3) As I mentioned, the Full-race mani and dual Tial WG's are the bulk of the cost - but he'd have to buy those anyway to put the 35R on his SR20, or 2JZ. That doesn't factor into the argument for which motor to use.

4) The 2JZ is a fantastic motor, especially if you're shooting for using stock internals - like you said, 25psi and methanol/nitrous is a recipe for 600+rwhp. Problem is, the motors are more expensive, and the swap is more complicated. Unless you're actually looking for 600+hp, I wouldn't even consider it over the RB25 (in my opinion, this is the only part of the argument that's debatable).

[boosted98gst]

I am was in the same boat as you, wanted a well built 240 that would be over 400 whp, I started with a sr20det the decided that it has to many weak points for what power goals I want. I ended up selling it and now im on my rb25 after going to a inline six I will never own a 4 cly turbo car again. it is night and day.

[Ali 556]

Originally Posted by GSXRJJordan)
2) The difference in spool with a GT35R will be greater than 1000RPM, from the dyno's I've seen (to be sure you'd have to have identical designs, etc) - SR's spooling at 4500-5000 and RB's spooling between 3000-3500. The point is, that's a [i

very[/i] important 1000rpm on the street.

3) As I mentioned, the Full-race mani and dual Tial WG's are the bulk of the cost - but he'd have to buy those anyway to put the 35R on his SR20, or 2JZ. That doesn't factor into the argument for which motor to use.

.

Sory,

I've driven more than 3 RB25 swaped S14 And One R33 GT-S (RWD) and all of them had a dream of no lag...All S14's had GT3582R and lets say that i've driven lag monsters from hell.

The R33 had a Gt3076R and that felt more like a good turbo and there is a response from it.

And PLEASE let not fight about pricing...we all know that RB = $$$ and the more you go the more expensive the parts become.

$$$/Hp KA win hands down granted most won't like the ''truck engine''..

So to stay on the topic...

OP

LS1 / KA / Or 2JZ still an option for you see the video that I've posted oh...And a GT4788R (88mm Turbo) get's F U L L boost @ 5500rpm On a 3.4L 2JZ

[racerx2k1]

Wait, he's newbie but he knows 2 specific users here?

Pinking extended for ghost240.

[atutt]

6L perhaps? There's 400hp right there without the spool time. Sell the turbo. Profit. Go 6L.

Seriously though. If you are seriously concerned about making lots of power and not having to wait for spool. A v8 would probably be a better way to go.

Just a thought.

[boosted98gst]

Originally Posted by atutt

6L perhaps? There's 400hp right there without the spool time. Sell the turbo. Profit. Go 6L.

Seriously though. If you are seriously concerned about making lots of power and not having to wait for spool. A v8 would probably be a better way to go.

Just a thought.

This is the truth you are either going to make power down low on small turbos or make the power up top in the rev's. The head/cam/valve train is whats going to make the engine. Like he said if your worried about spool time and that go with a LSX