i'm extremely lean on dyno 150whp - Honda Forum / Acura Forum

themi6group · 05-08-2002, 04:40 AM

i dyno'd my greddy turbo'd 98 civic ex yesterday and it's dangerously lean. i was running 8psi w/ intercooler, bov, black box, vafc, etc. producing only 150whp. across the entire powerband i was lean at 13.5 af ratio when i want to be 12.5. we tried everything to richen it but no luck. anyone have any suggestions? i'm still running stock injectors, 12.1 fp, black box, and vafc.

SoFlaGS-T · 05-08-2002, 06:18 AM

you should do some fuel mods... get a new fuel pump that makes higher flow and match that up with bigger injectors like 440's...

themi6group · 05-08-2002, 06:36 AM

yeah i have a 255lph fi fuel pump. 440's seem to large. are they ideal for 8psi?

Dr Drew · 05-08-2002, 08:04 AM

maybe i'm wrong but I thought the greddy kit came with aftermarket injectors... ?? or is that only the twin cam ??

themi6group · 05-08-2002, 08:46 AM

the gsr and si kit comes w/ the injectors. the 92-95 kit doesn't. after looking at my dyno sheets i've noticed that my injectors seem fine. now i'm suspicious at the black box. it's suppose to deliver fuel but it doesn' t seem to be.

Dr Drew · 05-08-2002, 12:01 PM

What was your injector duty cycle at peak ?? What is your Fuel pressure ??

b18c5turbo · 05-08-2002, 04:17 PM

get a vortech fmu this should resolve the prob

98AccordEX · 05-08-2002, 05:48 PM

cant you just make the VAFC make you run rich? i know its electronic and the mechanical stuff has to be able to push the fuel but i am running 6 lbs and i am running rich on stock settings on my VAFC

themi6group · 05-08-2002, 07:13 PM

you know fellas, i should've been runnin' hella rich but i was too lean. i'm running a 12.1 vortech fpr, fi fuel pump, greddy black box and vafc. i don't know what the duty cycle was but it was maxed. the vafc can only lean when your rich but there's a small amount of richen but not for me cause i was mad lean. i think i figured it out by disconnecting the black box. i really won't know until i get it dyno'd though. i'm gonna only run w/ the vafc and see what happens. thanks and if anyone has any suggestions on the setup holla.

Dr Drew · 05-09-2002, 07:10 AM

If the duty cycle reaches over 90% it isn't stable with stock pressure (~43psi static). Higher fuel pressure makes the duty cycle lower than what it would be with stock pressure. High fuel pressures make your injectors open slower than normal and not eject fuel properly. See if you can find a set of 97+ prelude or accord injectors cheap somewhere. They are 270cc compaired to the stock 240. You already have the AFC to compensate for idle duty cycle.

turbob16hatch · 05-09-2002, 07:16 AM

The stock injector is 260cc saturated type.

themi6group · 05-09-2002, 08:10 AM

oh i see, thanks fellas. i see the 97+ prelude vtec injectors are 280cc. i didn't know about the accord ones. cool

Dr Drew · 05-09-2002, 12:44 PM

My bad, I didn't realize the Lude injectors were 280cc, for some reason I thought they were 270. Here is a link to a post about injector size. BTW the civic/integra injectors are 240cc.

Injector specs

themi6group · 05-09-2002, 12:51 PM

thanks man,
anyone know what accord injectors would work?

Dr Drew · 05-09-2002, 01:07 PM

My friend had accord 270cc injectors on his C1. Don't know what year though...