Raceboy

There's NO boost leaks, confirmed.

Looking forward for experience, is it ok for the TPC supercharger boost to drop? At 5000rpm there's about 0.2 bar left.
I installed intercooler and standalone ECU with direct ignition and 630cc injectors, boost behaves identically both before and after IC install.

Here's the car:

Geoffrey

I have experienced the same thing. Just like a turbocharger, a supercharger is sized and can fall off efficency which is what you are experiencing.

Which ECU are you using?

Raceboy

Hi Geoffrey,
I'm using VEMS Plug'n'Play ECU that goes directly to Motronic 55pin connector and fabricated additional wiring for Wbo2, ignition outputs etc.
On this picture I did a "test session at the dragrace": best ET 12,77, best trap speed 177 kph and best 60ft 1,88 s.

Funny thing is that after 6000 rpm datalogg shows that boost rises by 10 kpa, to 132kpa.

Brett B

Sounds like you could be experiencing belt slip. The supercharger drive belt may be too loose or glazed causing it to slip during high load conditions. Maybe try a new belt and make sure the pulleys are all clean. You can also try spraying some VHT Trackbite on the belt, it is a temporary fix that helps to determine if belt slip is really the issue.

CornerCarver

+1

I like that intercooler setup. I am curious to know if it runs more efficient than the cumbersome TPC liquid intercooler.

Raceboy

This intercooler has very nice efficiency, intake temps are never higher than 8 degrees Celsius over ambient. And that's under full load.

I'll check the possible belt issue again to make sure it's ok and perhaps get a new belt.

MPB993

Hi,

I've had my TPC'd SC for about 5 years now and about 50 k miles. The fall in boost is expected and results from the SC providing a linear increase in flow with rpm whilst the engines capability to flow increases non linearly due to its cams/headers etc. Although the boost drops the flow through the engine remains linear with rpm as defined by the SC intake characteristics. There is another effect at higher rpms where the SC intake and cams/headers start to limit the flow and efficiency which is why the temperature goes up resulting in more pressure seen but the flow is decreasing. Having been through intercoolers chargecoolers, new belts etc etc on the setup this has been my observation but mine drops from .6 bar to .4 bar running a 2.6" pulley and w/a injection pre-SC so it could be a belt. I have also removed as many bends as I can between the air filter and the engine intake manifold to reduce parasitic losses.

BR, Mark.