3 Simple Questions About Increasing Boost On An R33

[blk94r33]

You can't be serious take all the boost out of it if you get two fans put them side by side and stand in front of them the big fan will flow more air then the smaller one it's same going for compressor wheels if you have a stock comp wheel against a gt30 wheel the gt30 comp wheel is bigger and will flow more. On my 20 the rb25 turbo got me 170 kw at 14 pound then I installed a td06 and made 220 kw on 14 pound the motor didn't decided oh yay new turbo I'll make power now it's the fact the td06 flowed heaps more for the same boost

Not if whatever's controlling the fans is set to slow the bigger one down once airflow reaches a certain point....

[GTSBoy]

How?

You can run the biggest turbo you want, if the actuator is only set-up to run 10psi into the inlet system, then the turbo will only FLOW enough air into that restriction to make 10psi. It can't cram 10 times the volume of air into the same engine without increasing the pressure?

Read my previous post about the ENGINE + TURBINE being the restriction that your boost is working against and try to understand it. The actuator has nothing to do with this argument.

[blk94r33]

Read my previous post about the ENGINE + TURBINE being the restriction that your boost is working against and try to understand it. The actuator has nothing to do with this argument.

I am trying to understand, genuinely.

The engine restriction hasn't changed, the valves/manifolds/throttle body etc still pose the same restriction to the incoming air as they did before. The gains are made by the engine not working as hard to make the same "boost", lower intake temperatures etc?

[GTSBoy]

Yuh. Big turbo = big hole to blow the exhaust gas through. If you have a big hole, then to maintain the same backpressure, you must blow through more gas. Or, the other way to look at it is, if you start with the big hole at, say, 10 psi back pressure, and make the hole smaller, then the amount of gas that will flow through the hole goes down. If you want to maintain the same gas flow through the hole, then you need to increase the backpressure.

So this is all a little complicated by the fact that our "hole" consists of both the engine and the turbine section (connected in series)....but it is still the same result in the end. If the engine remains the same, and you change the restriction presented by the turbine, then you change the restriction presented by the engine and turbine together.

And of course, we have to ignore all the other bits about when the boost will start, when it will run out of puff, etc etc.

Lower intake temperatures and all that jazz can and wil play a part, but for the sake of the thought experiment, you can ignore all those, assume that they remain the same for the big and the little, if they're both running at 10psi boost and somewhere good on each of their compressor maps.