Gonna turn up the boost..pls alleviate my concerns

[DrtyRat]

I'm taking my car to my mechanic today to have the boost turned up on my car. I have searched many online forums about turning up the boost on stock sr's and pretty much had my mind made up to go to 12lbs. However,(i say this next line w/much hesitation) I was reading SCC and came arcross a formula for figuring out injector sizing......

Crank HP x Brake Specific Fuel Consumtion
___________________________ = Injector flow (lb/hr)

# of injectors x Duty Cycle

then to get cc's....

Flow (cc/min) = Flow (lb/gr) x 10.5

Well when I plug in my #'s of 240 crank hp x BSHP(it states .6 for turbo'd cars), w/ the # of injectors (4) x .80 duty cycle and then convert it to cc's I come up w/ a # of 472.5 cc's...obviously since its stock I only have 370's. Is this formula way off? Is my Crank Hp estimate way off? Obviously I want to be safe but I'm itching for more power...Help Calm Me Down!...please

My setup...
S14 sr (t28 turbo)
FMIC
Supra TT fuel pump
3" DP
3" Test pipe
Blitz Nur spec exhaust
....no fuel management and stock maf

[93 240sxfastback]

Just get the injectors. It's better to be safe then sorry, and get some kind of tune.

[tre]

wow you think too much haha.

550cc (or is it 555cc?) Nismo's go for it :P

[spdfreek0o]

Your definetly going to need bigger injectors, but also think about 555cc at an 80% duty cycle is ony 444cc. so you will either need to get bigger injectors and lower the duty cycle or get the 555s and raise the duty cycle. But alot of people suggest not going over 80% duty cycle on injectors. Talk to Dave @ Deatschwerks and he'll hook you up with what you need.

[NemeGuero]

Word.. Deatschwerks will take care of ya.

[DrtyRat]

yeah I know what you guys mean w/getting the bigger injectors (as a matter of fact I'll be getting 550's from Deatschwerks) but It's not like I can just slap in the larger injectors and walk away from it. I plan on my next mod being the SAFC and then save a lil and get the injectors. BTW I got the homedepot mbc installed today and w/it all the way closed it wont go past 10lbs. I somewhat happy w/the power it added but does it sound right that it would only boost to 10lbs? My mechanic says that he may have to "adjust" the wastegate spring but he was in a rush to get home.

[FIA Nissan]

Get a stiffer spring on the MBC.

[DJ_Sunrise]

i run about 11-12 lbs of boost daily on my s14 SR as well, with no problems. heres my setup
apexi pfc
mr downpipe + turbo outlet
apexi n1 dual
304 steel intake pipe
blitz lm fmic
this is as far as any power mods go..
my car is untuned, and it runs perfectly fine. the one day where i did hit 12lbs of boost around 7k rpm i hit 85% injector cycle. keep off anything past 6k rpm at anymore than 10psi and you will be more than fine, unless the only reason i am is cuz my pfc is so super duper.. hmm. haha. btw, ive heard different things, but supposedly the SR mafs max at 240whp? so you may need an upgrade. i have about 260whp, and run fine.. so i dunno..

-Bart

[DrtyRat]

Thanks for the info DJ...I'm sure having the PFC is helping you but your post does help w/my concerns.
BTW...where can I get a stiffer spring?...thanks again guys for the help