toothdoc

iTrader: (7)

Can anybody tell me at what point I need to upgrade from the stock injectors? My car will have an LS6, full exhaust, FAST intake, under drive pulley and Comp Cams 228/228 .588 .588 112 + 2 degrees when it is done. Will the stock injectors be able to support that, or should I upgrade? If I should get bigger ones, how big? Thanks for any help.

SS1875

iTrader: (34)

More info needed...what kind of car and what year do you have?? Fast 78, 90, 92? Stock heads? etc.

12secSS

iTrader: (30)

For your mods, I would suggest getting at least 35lb injectors (rated at GM spec 58psi). A good replacement is the Ford SVO 30lb (rated at 43.5psi) red top injectors. But, do you plan on doing more mods? What is the power goal? That will dictate if you need to step up to 40-45lbers.

massls1guy

iTrader: (9)

I asked my tuner what size to get. You need to change your tune when you install different injectors so the best time to swap them in is when you get the cam tuned. For the mods you list you can probably go with the ones I have - Ford racing 30# red tops (which flow 36# in our cars because the fuel pressure is higher).

edit: I guess I restated what 12secSS said... we submitted at about the same time. sorry.

toothdoc

iTrader: (7)

I knew that I was leaving a few things out.

98 Z/28. Stock LS6 heads. Fast 92 intake. No further mods planned.
I realize that I will need a tune and I will have Speed Inc. take care of that after the engine is installed.

SS1875

iTrader: (34)

Your probably okay with the stock injectors, I believe they are 28# for your current application. The 30# Red Top SVO's would be a nice bump up and give you a little more to work with. If down the road you decide to make more changes, you may consider the 42# SVO's. Good luck with it all.

Turbo.TransAM

iTrader: (1)

42lbs and downtune.

'02 WS6

iTrader: (73)

Ford 30s or a set of 36s from FICINJECTORS. Either of those will be fine, it's what I'm doing.

zman1969

iTrader: (91)

I had the same question as the thread starter- almost same mods- fast 78 Livernois CNC heads TR224/224/112 cam looks like wile im assembling this, I shoud do these SVO inj too - are the a "bolt in"? same size,connector? Im shooting for 400-425 RWHP through a M6 and a 8.5" rear

01ssreda4

iTrader: (96)

can you go with too big of an injector? like being cam only and getting a good deal on 42lbs so you put them in there.

12secSS

iTrader: (30)

Yes, the red tops would be perfect. Stock 28lbers can support up to 450rwhp, I would estiamte the 30 lbers would go to 550rwhp, both on N/A setups.

Yes, you can over injector your setup. But not as bad as other things. A good example of too much injector would be running Mototron 60lb injectors on a stock setup. The reason is that during idle and part throttle cruising, the injector duty cycle is very minimal. Injectors have a minimum duty cycle (on/off ramp time) that they operate at, you should not operate near or below that. Much like operating above the max duty cycle.

You would be ok with cam only and 42 lbers, especially if you plan to use nitrous in the future.