Thread: 6262 dyno Results and freeway vid p30

Well, the twin scroll spools the turbo too fast. With the .78 housing the surge sucked. Anything more than 12-14psi would surge, even with the ported shroud. I didn't want to damage the turbo, and the engine still felt choked up. So I went with the 1.06. It helped a lot, but mid-boost with mid-gear still creates nasty surge. I feel like the housing not flowing enough is choking the engine and creating this surge. I didn't have this problem with the VET cams, or with the open housing... then again the turbo didn't spool nearly as fast.

I would love to sacrifice just 100-200rpm spool to get better top end and cure the surging. We will have to see. I have played with the cams a bit and around 4000-5000rpm when the surge happens, I can cure it by not switching the cams. On the dyno, I kick the cams early because they show big gains in spool, but the load is less and the surge goes away. Bigger housing would slow the spool a bit and cure some of the surge?

When I see this graph and compare it to where I was on the dynojet last time, they look almost identical. Except I was running 26psi boost, making nearly 440wtq. The torque just dropped like a rock after 5k, and the power peaks at around 7k. It is interesting because on low boost, the engine peaks hp at 7800. As the boost gets turned up, it moves the graph pretty far to the left.

If I can just keep it over 320-330lb torque then this thing will be a beast. What do you guys think the higher lift and less overlap will do on my particular setup. I am excited to see. But a lot of people seem to have good top end with the SR16 cams, I did not. Power on low boost is great, but after 14-16psi the power per psi drops substantially. 12hp/psi is great, but 6-7hp/psi sucks.

At the very least I have cams which are designed for the 2.0, with faster opening speeds and a more steady torque output.

Does anyone know the LSA of the SR16, SR20, or 20V cams? I wonder what the difference is between them...

Sounds like a restriction on the cam and/or turbo & manifold.

Was this after you installed your new exhaust manifold?

Yes, this is ever since I put on the manifold. There is def no restriction there. It just spools too fast on the street. If I go part-throttle until 6k it is usually fine. It was a lot worse with the .78.

Turbo size if my guess , 3076 is like Comp, 57mm ind. 76mm exd, Turbine 60mm inducer and somwhere around a 53mm exducer. you are definetly wanting top end power more than response now. If its roasting tyres too much try some toyo proxes ra1's, it will minus the hard hit to limiter when breaking traction and give you traction travel instead.

its a 57mm turbo you have, a PT BB 6262 billet is gonna be ridiculous on your setup. You will gizz your pants doing this change guranteed, but again it sounds easy say but alot to do.


with the Turbonetics 62mm Turbo T4 and .86 a/r we said the same exact thing for first gear as it was spooling too quick on a 4wd car on 1st gear , raised the rpm from 8k to 8.5k, thats was on stock head and cams btw.

Ya, I have been on the fence of a larger turbo for years. Mostly because i hate lag. I want 500hp with as little lag as possible, while keeping it somewhat simple. If the GT3076r can get me there then I won't have to change anything. I've even toyed with idea of GTX3076r in order to give some head-room for my goals.

Good to know that I didn't mess anything up. With all the changes with the setup and wiring, the car started first shot. And the 4ga cable is working awesome! Even in the trunk, 4ga wire started the engine instantly. I am very pleased. Now I just have to do some touching up.

If it helps...

SR16VE -
LowLobe 116.5LSA (Lobe Centre 111 intake/ 122 exhaust)
High Lobe 105 LSA (Lobe centre 100 intake / 110 exhaust)

SR20VE -
Low Lobe 116LSA (Lobe centre 110 intake / 122 exhaust)
High Lobe 109 LSA (Lobe centre 104 intake/114 exhaust)

SR20VE 20v -
Low Lobe 110LSA (Lobe centre 114 intake /106 exhaust)
High Lobe 111 LSA ( Lobe centre 114 intake/ 108 exhaust).

Have you considered having the housing extrude honed? I have thought about that for mine. I could have sworn I read on motoIQ that is was good for spool.

I don't like the idea of grinding because it seems like it could be left uneven and effect spool in a negative way.