Thread: Getting more power out of my SR

Ok I have a redtop SR20DET, probably about 25k miles since a rebuild. Stock internals with ARP head studs, walbro 255, STI injectors, cast top mount, T3/T4 .63 ar, nismotronic ecu converted to MAP, running 18psi right now. I'm tired of getting beat so I need more power. I don't get any knock right now on 93 octane so could I turn the boost up any? or should I? What about a 50hp wet kit to help turbo spool quicker, water/meth injection to run higher boost? Say fuck it and save up for cams? I'm guessing its around 325hp right now and its not enough. Really considering building a twin scroll manifold and trying to find a deal on a GT3076R and bigger injectors to. But until that happens I need more.

Aside for a professional tune, I would say the manifold and turbo is the way to go.

Yea thats what I was thinking. It already has a pretty aggressive timing map in it right now, and 11.8 AFR under boost. Get zero knock and pulls good, its just nowhere near enough. I'm looking for a turbo but until I find one I gotta do something. I'm running STI 513cc injectors right now, thinking about ordering the DW 850s to swap out for these. Put some E85 in it retune fuel map and crank boost up to 25. That should make it a little faster. Short of S4 cams and better turbo though I don't see to much of a gain from anything else.

E85, injectors, 320lph pump, more timing and 24psi if your turbo can handle it.

First thing, go to a front mount.

Second thing, get rid of that 1970s turbo.

I have a FMIC already. I'm kind of at a crossroads on a new turbo right now. I know my goal for this car and I don't want to buy a turbo now thats going to be to big for what my bottom end can handle. I'm most likely going to wait until I get rods and pistons. Also I'm in the process of doing a CD009 trans swap and q45 diff so my drivetrain can handle the power and launching on my ET Streets.

Sorry, I was reading fast and saw "top mount" and even though it's a RWD car I still thought the wrong thing. =(

I wonder if you might find that a GT3076R or similar turbo will give you way more area under the curve and satiate your desire for acceleration at the same time. The bottom can handle that turbo, no problem. But so can the transmission and rear diff. You're upgrading those? If you think you need those components to handle your future plans, then I'm pretty sure you're going to want to change everything, not just the turbo.

As for making more power with what you have, I imagine your injectors are maxed out. You'll need higher flowing injectors first for sure. You could potentially run up to around 25 psi with your fuel pump and make near 400 WHP but you won't do it on 93 octane. Some water/meth injection will get you there. Without dealing with the octane situation, you're basically at the limit of that turbo if you ask me. Those things are notoriously out-dated. They blow a lot of hot air.

I have thought about a 3076R and a custom twin scroll manifold. My synchros are going in my trans so I figure its time to ditch the stock trans and J30 diff. One reason is it will handle the power I'm wanting to make eventually, and the other is I run autocross and the gear ratios in the CD009 will be better for that. I found a JK40C trans but have heard a few bad things (not sure if they are true or not but I don't want to take chances) I want my drivetrain to be able to handle whatever I put it through.

My injectors are at about 80-85% right now I think. I would have to do a log tonight to check I don't really remember. I have thought about the water/meth but not really sure how it works or exactly how far I can take it. Yea I'm sure this turbo is holding me back though. SMH it cost money to go fast lol, im learning this lesson again.

I recently put together a DIY <100$ water injection kit. Check out my buildthread for inspiration.

My injector duty cycle is 95% on E85, and having some water gives me some added security. I use my VET as a learning platform, I want to do all the tuning myself so having water AND E85 should make for a more forgivable setup. I can't tell you how much the water actually helps in avoiding knock, since I only have the stock knock sensor which isn't really that reliable at high rpm combined with prothane engine mounts.

Adding water/meth shouldn't have to be a costly project, since Nismotronic offers great ways to activate it at specific boost levels.

Where are you getting beat at? why are using stock piston on rebuild engine.? Forged piston is cheap enough. Stock sr piston is pretty weak I cracked my piston at 350 whp. I will do forged pistons and rods before adding more power . Getting power to the ground is very important too. A million hp would not give you any benefit if you cant put it to the ground.