On a 2000 Honda Civic SI the Helms says that the Fuel Pressure should be between 40-47 psi for a b16a2.

Now I have a 255lph in-tank fuel pump and 450cc injectors what should be a healthy fuel pressure for my boosted SI?

 

IT depends on how much fuel you need, if your injectors are too small you can force more fuel throught them by raising the fuel pressure, but stock FPR is good to 900 injectors and about 400 or so horesepower.

 

so would you say that a healthy pressure would be within the stock specifications? I am pushing 275 whp 218wtq

 

You should be fine running stock fuel pressure. If you have a stock FPR then you pretty much have no choice but to run stock pressure anyways. If you have an adjustable FPR (you didnt say if you did or didn't), then you can keep it at stock pressure. Once you start dealing with larger injectors like 650-1000cc's then you'll want to lower fuel pressure slightly to improve idle on bigger injectors. In some rare cases installing a larger fuel pump will cause the system to run at a higher pressure. If that happens then you can use your adjustable FPR to lowr it back to stock pressure.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlueShadow &raquo;</TD></TR><TR><TD CLASS="quote">You should be fine running stock fuel pressure. If you have a stock FPR then you pretty much have no choice but to run stock pressure anyways. If you have an adjustable FPR (you didnt say if you did or didn't), then you can keep it at stock pressure. Once you start dealing with larger injectors like 650-1000cc's then you'll want to lower fuel pressure slightly to improve idle on bigger injectors. In some rare cases installing a larger fuel pump will cause the system to run at a higher pressure. If that happens then you can use your adjustable FPR to lowr it back to stock pressure.</TD></TR></TABLE>

not meaning to thread steal, but what pressure would you recomend running on an h22 using 1000cc (to help out the idle)... thanks

 

What I posted above was just what I read from my "how-to tune" book. Lowering fuel pressure takes some relief off of the injectors pintles (or whatever) at low idle. But after a brief search I've found that most people on here set their fuel pressure at 30-40 at idle for 1000cc's.

 

sweet man... thanks for the help/info/time...