Dubai944

Here is a sample of logged data for pressure and temperature drop at full throttle through the rpm range during a track test today. (pressure values are absolute not boost)

This is with a stock turbo intercooler being run in the reverse direction. In my case there is a significant pressure drop, up to 4 psi at some points.

Pressure and Temp Drop.pdf

TurboTommy

Thanks for posting
So, are you saying you ran only roughly 0.5 bar boost?
What was the ambient temperature?

Jfrahm

How much of the pressure drop is attributable to the cooler, denser gas after charge cooling? I imagine an intercooler that does not show a pressure drop is not cooling the charge.

Dubai944

Ambient pressure is roughly 14.5 psi, although both sensors were reading 14.1 with the engine off yesterday. Max manifold boost on my car is 9 to 10 psi. You can see that pre-intercooler boost is as high as 12 psi. 3 to 4 psi loss when you are only running low boost like this does not seem very efficient. I imagine it would just get worse with higher boost levels.

It was 30 degrees C yesterday and very humid.Quite warm.

Dubai944

As I understand it if you increased the flow on the standard intercooler, such as opening the end tanks up, to reduce the pressure drop you would see less cooling, however a bigger more efficient intercooler should be able to achieve the same or better cooling with less pressure drop. I was actually surprised by how well the stock intercooler cools down the air. The supercharger on my car creates a lot of heat, not sure what sort of pre intercooler temps you typically get with turbos.

333pg333

Which track were you at Steve?

Dubai944

Lakeside again. Got black flagged twice for "excessive noise" even with my "quiet" exhaust! Ended up running around shifting at 6000 rpm instead of 7000 rpm and rolling off the throttle every time I passed the tower and managed to stay out for one full session without the noise ***** complaining.

333pg333

So they didn't even register your times due to Black Flag? I wouldn't have thought Natsoft would do that...

Dubai944

I only did the practice sessions, so no Natsoft timing. No point hanging around for the timed runs if I couldn't run flat out. Despite short shifting everywhere and running only 90% throttle on the front straight to beat the noise meter, I was still lapping a lot quicker than any of the cars there. The car was handling really well compared to last time out with a few changes I have made.

333pg333

You should really have your own thread that you can update when you make changes. Then all these interesting aspects of your car can be found in one place Steve. I'm sure there would be enough interest in the car.

Dubai944

Haha. I have a couple of threads going elsewhere. I'm not organised enough to have just one!