I have a 3 Bar FPR on my car with everything else stock, but the chips. Does the 3 Bar FPR provide the engine with 3 Bar of fuel pressure at ALL times, or does the fuel pressure increase onlywith boost?

i.e. Does the car now have 3 Bar of fuel pressure even at idle?

I spoke with the folks at Marren Fuel Injection and they said this might be the cause of the gas odor in my engine oil. Of course, they doubt the injectors they serviced for me are leaking.

Thanks!

 

No, but you are running .5 bar more pressure at all times. The 3 bar rating is a a static rating (i.e no pressure positive or negative applied to the hose nipple).

Only with the vac line disconnected, with the vac line connected and say 17inhg vacuum (~.58bar) you are providing 3 - .58 = 2.42 bar of pressure to the injectors.

So basically with the 3 bar regulator on vs. the factory 2.5 bar, you are providing ~10% more fuel at all time.

RC-Engineering's tech page has the formula to calculate flow rate changes due to pressure increases

Rob

 

Thanks Rob.

So would the extra 10% of fuel at idle result in unused gas seeping past the rings into the cylinders?

 

Good question, do we need to make adjustments to our a/f mixture when we add the 3 bar reg? Otherwise, wouldn't we just be dumping too much fuel into our system? Would turning up the boost compensate?