warheart

Hi guys!
I´m building 383 stealth ram it´s gonna be my daily driver. I´d like to get some ideas what injectors and throttle body would be suitable with my specs.
It´s conservative set up with compucam 2032 (214/220@.050), and CR around 10:1. I´d like to get lots of torque and still decent gas mileage. Also do i have to get a custom chip??
ok thanks
martin

warheart

Oh the heads are stock TPI....

warheart

anyone???

Jza

I went with 30# on a similar setup. Gives you a good range to work with and doesn't overwork the injectors if you up it's duty cycle.

grumpyvette

your injectors need to match the airflow requirements and hp levels the engines likely to see. with that cam you might be able to use the stock injectors, but certainly anything in the 24lb-30 lb range should work reasonably well. my HSR 383 has 11:1 cpr fully ported heads and a much larger roller cam , 30 lb injectors were at thier max limit in the upper rpm range but worked reasonably well, I swapped to 36 lb and they work, keep in mind Im running at about 475 flywheel hp, with that cam & cpr Id doubt youll exceed 420hp, so 24lb-30 lb will easily supply the engines needs, btw get an adjustable fuel pressure regulator on the fuel rails and a gauge, knowing the fuel pressure and having the ability to adjust it makes tunning easier

http://store.summitracing.com/partde...art=SUM-800199

http://store.summitracing.com/partde...5&autoview=sku



http://www.z31.com/software/injector.pl


http://www.rbracing-rsr.com/fuelinjectors.htm


http://users.erols.com/srweiss/tableifc.htm

http://users.erols.com/srweiss/calcpchg.htm

keep in mind the HSR intake port flow rates are far higher than the stock heads and can be ported to flow even better, so aftermarket heads, a low restriction exhaust, higher rear gearing will be needed to take full advantage of the EFI INTAKES flow potential

warheart

ok but what about TB i was thinking of 52mm or 58mm BBK also i saw a 54mm remanufactured one on the ebay.. the TPIS is a bit expensive and do i need a new chip or the stock ECU would be fine?

grumpyvette

your NOT likely to see any major gains going from a 52mm to a 54mm-58mm
yes it will flow more if you do a few mods but the current combo will easily be supplied with the stock tb,keep in mind they use the same TPI tb on the 502

bbc factory injected combo,
http://www.sdparts.com/product/12499...eAssembly.aspx


Id suggest staying with the stock TB untill youve installed all other mods, like a full 3" exhaust, a cam with more durration, a 3.73 rear gear and bigger aftermarket heads, yeah, a bigger tb looks cool, but the gains are minimal at best, save the cash for the bigger exhaust and better heads that give you better results. youll need to do tunning and a custom chip may help, but you can do a good deal with the modded stock setup if you understand how everything works ,before its mandatory

warheart

thanks grumpyvette, who makes good custom chips??

customblackbird

iTrader: (15)

idk how u would make 420hp with stock TPI heads.... unless they are the aluminum vette heads and are ported like crazy. a 383 with the head and cam combo might make 350hp bc the heads are killing u, the HSR/cam are outa the range of the stock tpi heads especially on a 383. the stock heads dont flow enough for a 350... let alone a 383. even if the are ported like crazy... an upgrade to vortec heads yeilds 40-50hp over a stock TPI head with a stock cam. if u where to add vortech heads u could see 400-430 crank hp.

im building a 383 hsr now and i got patriots aluminum 195cc heads, hsr, comp cams XFI cam 230/236 at .56/.57 lift and 1.6rr and i might see 500crank hp. im gona be going with 30lb injectors that should be good to about 450-475 hp then u just bump the fuel pressure. urs wont see 400hp so i would get 24-26lb injectors. stock lS1'S etc run 24lb injectors and they are pushing 330hp stock. the stock TB should be ok up untill 375-400hp then it becomes a restiction, even tho its known that u should upgrade to a 52mm with 350-400hp 350. im going with a 58mm TB tho bc i'll be making more power. ur 383 is gona want alot of air and the HSR will give it and ur cam seem ok but u will see huge power gains with aftermarket heads.

just a hint... dont waste ur time with the stock TPI castings they arent worth it... u'll spend 600$ just getting them redone without porting or machine work and for 100$ more u could get vortecs or another head for not that much more.