Hey guys,

I was wondering, since vacuum is required for the proper working of the brake booster and FPR, how does it work under boost (in which case there's no vacuum)?

For example I understand that you never brake and gas at the same time (for street driving) but what about the FPR? How does it work under boost when it requires vacuum for the proper working?

Thanks a ton!

 

the brake booster has a check valve, so no worry. the FPR raises the fuel pressure 1psi for every 1 psi of boost to keep flow the same against the added air pressure in the runners.

 

http://www.trade9shoes.com

 

So does the stock FPR on a civic work with boost or only with vacuum?

 

i wouldn't say never. brake boosting!

but the fpr does work under boost.

 

i never got brake boosting to work on the highway
how do you guys do it?

 

Basically your holding the brake to put the engine under a load while maintaining a certain speed and, most important, building boost. Once you got the pressure you want then let go of the brake and feel the power or wheel spin. Thats the way I look at it.

 

i have hold the brakes on the hway and throttle and t wont build any boost