i am doin a N/A set up with upgraded pistons, rods, rings, entire head so what size would be best any help would be sweet

 

I can't see where 550's would hurt. But don't take my word for it, for all I know you could be fine with 720's.

 

WTF? What is your setup. That might help a little.

 

what kind of compression are you running?

 

the real question is, how much power do you anticipate to be making? the stock injectors can support quite a bit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by motrayEG6 &raquo;</TD></TR><TR><TD CLASS="quote">i am doin a N/A set up with upgraded pistons, rods, rings, entire head so what size would be best any help would be sweet</TD></TR></TABLE>

Assuming your gonna run High compression and a pretty aggressive set of cam's i'd reccomend some RC 310's. No way in hell would you need some 700 injectors, way to big IMHO. I'm running an integra gsr fuel pump and rc 310's on my 12:5:1 cr b18c1 and it matches up very nicely.

 

"MOST" n/a builts are fine with stock injectors, N/A 240s are good until atleast 250whp, boosted not so much.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by schardbody &raquo;</TD></TR><TR><TD CLASS="quote">"MOST" n/a builts are fine with stock injectors, N/A 240s are good until atleast 250whp, boosted not so much.</TD></TR></TABLE>

x2

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jimmy &raquo;</TD></TR><TR><TD CLASS="quote">

Assuming your gonna run High compression and a pretty aggressive set of cam's i'd reccomend some RC 310's. No way in hell would you need some 700 injectors, way to big IMHO. I'm running an integra gsr fuel pump and rc 310's on my 12:5:1 cr b18c1 and it matches up very nicely.</TD></TR></TABLE>

x2

rc 310's are probably the way to go. but yeah. like everyone said, your setup info would be nice

just be sure to get your car tuned after you pop in those injectors. a great tune goes a long way

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by schardbody &raquo;</TD></TR><TR><TD CLASS="quote">"MOST" n/a builts are fine with stock injectors, N/A 240s are good until atleast 250whp, boosted not so much.</TD></TR></TABLE>

I highly doubt you can get 250whp on stock injectors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sal &raquo;</TD></TR><TR><TD CLASS="quote">

I highly doubt you can get 250whp on stock injectors.</TD></TR></TABLE>

im sorry you feel that way, i have personally gotten 225whp on stock 240s, and they werent maxed.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by schardbody &raquo;</TD></TR><TR><TD CLASS="quote">im sorry you feel that way, i have personally gotten 225whp on stock 240s, and they werent maxed.</TD></TR></TABLE>

Wow, almost every car ive ever seen with stock injectors usually top out at approximately 200whp give or take a few hp. What were you revving your motor to? Also what was the duty cycle of the injectors?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by schardbody &raquo;</TD></TR><TR><TD CLASS="quote">"MOST" n/a builts are fine with stock injectors, N/A 240s are good until atleast 250whp, boosted not so much.</TD></TR></TABLE>
IMO with anything past 200whp the 310s should be used. simply for high RPM injector duty cycle reasons. the 240s will do 250whp but they will make you unhappy over time. (random/odd problems as they die)

NOTE: it's fairly commonly accepted that anything over 80% DC is shortening the life of the injector

 

ooh. dont forget having a high pressure fuel pump such as a walbro 255 is extremely helpful, with or without the stock injectors.

 

255lph is too much for N/A apps, the 190lph is more than enough.
Plus installing the 255lph without a high flow FPR your fuel pressure will be higher at idle which will cause a rough idle and if things get bad enough a CEL.
Tuning can take care of this but it makes things more difficult than they have to be.

 

i made 241 whp on rc 440 injectors.

 

thanks for the help i will go with the 310s and a 190 fuel pump u guys helped out huge thanks again

 

If you're running a stock GSR or SI fuel pump now you won't need to upgrade it.

 

here maybe this can help http://www.rceng.com/technical.htm#WORKSHEET

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sal &raquo;</TD></TR><TR><TD CLASS="quote">Wow, almost every car ive ever seen with stock injectors usually top out at approximately 200whp give or take a few hp. What were you revving your motor to? Also what was the duty cycle of the injectors?</TD></TR></TABLE>

yeah, at stock rail pressure they do depending on max RPM, the motor im referring to was a built LS gude (bullfrog) top end and ECU. was revving to 8200rpm and making power the whole time. i didnt tune this motor myself, so i cant say what the exact duty cycle was but i know rail pressure was like 55-60psi. im certain i would have been told if i needed bigger injectors, then again, maybe they didnt care enough to let me know. i dont know, i got rid of the car a few months after the dyno time.

 

I can't see where 550's would hurt. But don't take my word for it, for all I know you could be fine with 720's.


sry, i lol'ed at this. injectors of that size are for SERIOUS turbo apps.

 

i am running a b20b block and gsr head

 

also could i get away with useing b18c pistons or do i have to find b20 pistons

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by motrayEG6 &raquo;</TD></TR><TR><TD CLASS="quote">also could i get away with useing b18c pistons or do i have to find b20 pistons</TD></TR></TABLE>

you need 84mm pistons to match the b20's bore. stock b18c pistons will not fit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by doood &raquo;</TD></TR><TR><TD CLASS="quote">you need 84mm pistons to match the b20's bore. stock b18c pistons will not fit.</TD></TR></TABLE>

sure they will fit.........very loosely.