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Definately. I have another 2 hypergears to tune soon. Well 1 until Kasko buys his ss1

You'll most likely make that 3 soon, I called you Wed night - still pretty keen to let you tune the SS2 on my auto GTT

See the way I see it if you are running the max airflow a turbo can provide at redline, then that same airflow at x psi will be x+y psi in the midrange, hence you should run more boost in the midrange to make the most of the turbo.

Like if you look at the compressor map then the same airflow at redline at 20psi is 25psi in the midrange. So if you can get away with running more boost at redline, you should increase the midrange boost to make the most of it.

Which is why I think turbos should be set based on airflow not psi. Though if you do it this way you are always going to have a massive midrange spike and have torque fall off by redline which just doesn't feel as good for some people, though for drifting etc it is perfect.

Thoughts people?

Well for a start you will have a LOT more cylinder pressure around peak torque, where you don't want it..

cheers

darren

Edited by jet_r31

Look at the 3L TT inline 6 BMW engines, all sorts of trickery to keep the torque flatish and not have massive peaks like our cars.

But the sharp rise is what makes a fun street car and makes passengers grab the jesus handle. ;)

JET 31 - Why dont u want maximum torque? Thats the funnest part, yes its more det prone there but if the fuel is good enough then there is gains to be had, then let the boost build to redline and make crazy power figures.

If only...

Tao i agree, E85 is cheating. 98 is the devil.

I think its more to do with the wastegate gate setup. When Trent did the internal and external gated test, the hug drop in internal gate setup means the turbine is cooping with high exhaust manifold pressure as well as heat after certain rpms.

From experiments that I've conducted a large external gate acts as a secondary turbine that carries out compressor flow only when needed.

So getting good results from an internally gated setup: Comp flow = turbine flow

on the external gate perspective: Comp flow = Turbine flow + External gate flow.

As if I run G3 compressor onto a SS1PU's turbine with a large 60mm external gate, I should get the 300rwkws peek power from the G3 while having the 20psi by 3300RPMs response of the SS1PU. I will do some tests on that when I’m over with stockie boltons.

Well for a start you will have a LOT more cylinder pressure around peak torque, where you don't want it..

cheers

darren

You always have peak cylinder pressure at peak torque... that is what peak torque is. What I am saying is you can increase your midrange torque for any given redline torque if you are running flat boost. Assuming of course you are not limited by detonation due to fuel etc.

Tao i proved exactly what u are saying with my old sr20 and .6 disco potato. I changed it to a 50mm external gate setup and made an extra 15-20kw all over. Its amazing how much extra the car can breath

JET 31 - Why dont u want maximum torque? Thats the funnest part, yes its more det prone there but if the fuel is good enough then there is gains to be had, then let the boost build to redline and make crazy power figures.

If only...

its a traction thing..its the way the max toque is delivered..

I know my with old turbo came on so much smoother with a factory airbox even ,just putting the pod on it would make it snap noticably harder into boost/max torque making it easier to lose traction ,which is fun but I prefered the smoothness and tractability with the airbox, even if it was making a few kw less...I could feed power on hard without slipping around or kicking out so much..

Guess it depends if you want to slide or drive..

Ur on ur own with that one. I see it as even if u have the power to break traction, with the correct throttle control u can be just as fast

IE me and you testing animals in the rain lol

Im just sayin it was a little easier to drive, not as much skill needed just smash it and go...

Sure you can do anything with "correct throttle control" but hey, if you have skill you dont really need synchros in your gearbox either...but they sure do make life easier...lol

Some Modifications that I've done to a stockie R33 21U turbo:

4inch inlet adaptor with SS3 comp wheel:

1.jpg

2.jpg

Looks all sort of stock I guess.

3.jpg

Would be awsome if I can crack 300rwkws with it internally gated on pump 98. :D

does it really need to be 4"? lol

cant it just be 3"?

Nope, the comp inducer is larger then the 2.5 inch inlet they had there. Had nothing left to clamp hose on after machining. lol

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