Hi guys I am getting a pulley upgrade for my procharger supercharger from 9-12 psi sci trim and I am using my
original injectors on my gta-5.7.
my only time slip for last year was 13.7 1/4 mi. at 102 mph.
I calculated my flywheel hp at @ 350-375 at most so if I ad
the 12 psi pulley i figure @ 400 hp at the fly wheel.
so I used several calculators and read lots about injector size.
My car is not a daily driver but it drives like one (idles,sounds,etc good)I use on weekends.I was thinking of getting 26#injectors but found that lots of people had problems with the smaller sizes with a certain
manufacturer.So,then I figured the 24# ford racing(svo)would flow@ 25# at stock pressure.

I have tuned the chip for injector constant fan settings etc...

what is your advise ?
Is the 24# svo going to be the best fi for cruising but the duty cycle will be too high when racing a couple times a year?
Or
Is the 30# better because it can be used at cruising part throttle applications and have plenty reserve.
I assume and hope the only chip change needed will be the injector constant.
also I intend to get a fmu recal kit from ati when i upgrade.

Any of you guys that have experience I would appreciate
your advise thanks.

My car is an 89 gta edelbrock ,headders, dual cats, edelbrock exhaust,procharger sci 9psi supercharger
subframe connectors wonderbar,msd ignition,adj pres reg .

 

I would go with the 30 lbs injectors. I am suprised you still run stock injectors. I am running 24 lbs in my NA motor making 350 to the crank. I would at least get 30lbs. Also turning up the fuel pressure isnt always the way to go. Because when you do that your injectors become inconcistent. At least that what some one told me.

 

I just bought some 24 pounder Fords from Summit for my upgrades later this year. I run a Vortech on a 305 and am adding heads and a Crane 2030. I figure with an 8X fmu, the 24#'s will allow me all the power I'll make and some reserve. I was told by a Vortech technical advisor that Rochester injectors will "slam shut" at around 70 to 80 psi, and sometimes just cease to work. Obviously, leaning out is bad. Leaning out under boost is potentially catestrophic, so my advice is get the biggest size that you can readily tell your chip to "deal with." Given your combination, you could probably use 30#s.