lt1 power

went to the track last night with my 94 trans am that i just purchaced not long ago, it has lunati cam and stock ported heads, 355 with 2500 stall and 4.10 gears , i raced my dads 08 ls3 corvette which has bolt ons and dynoed 417rwhp, i ran 12.3 @ 112, he ran 12.6 116, but at around 6000 my car seemed to break up at 2-3 shifts and i beleive the stock injectors can not handle the power im making, what do you guys think?

jay97lt1

Has it been tuned

lt1 power

yes it has pcmforless tune

jay97lt1

I had my car mail order tuned and it sucked I even had it dynoed tuned with crap results I would datalog ur car to see what it is doing. Iam running stock injectors right now on my 383 becuz my tune was way rich Now iam tuning it myself with help from some guys on here

RamAir95TA

iTrader: (2)

Multiply your flywheel HP by .07 and that is the injector size you should use (assuming an 80% DC).

JB_97ws6TA

iTrader: (6)

I don't understand how this is relevant, breaking up and missing is usually ignition related. Now if it is popping and knocking at high rpm than I would consider a fuel related problem. Stock injectors are probably working like a rented mule on a cammed car. I was running a lunati cam in my cam only build and I had 30#svo injectors at 80% duty cycle. Like I said, if it is a miss than it is in your ignition maybe you have an arcing wire, if it just falls on its face than it may be fuel related but I would start with fuel pressure before blaming injectors. Have you upgraded your fuel pump? Have you put it on a wideband to see what your AFR is at WOT?

lt1 power

as far as i know it still has stock fuel pump,the ignition consists of autolite 106 gapped at .45,taylor 8.2 wires, hypertech 4055 coil, and stock opti.

RamAir95TA

iTrader: (2)

How big is the camshaft? You're running a stock pump with stock injectors on a heads/cam setup? I'd get a scanner on your setup ASAP and see what the injectors DC is doing, along with a fuel pressure test/wideband test. You've got to be close to maxing out the capabilities of your fuel system.

JB_97ws6TA

iTrader: (6)

holy hell I missed the stock ported head portion of the original post! That thing needs injectors/fuel pump and a wideband/dyno tune if it is not super lean I would be surprised

robsquikz28

iTrader: (246)

Thats exactly what I was thinkin. You probably need 30 lbers in their asap

IronOutlaw

iTrader: (4)

What do stock injectors look like? I just bought a 94 and the injector caps are yellow and I don't remember my other cars having yellowtop injectors?

96capricemgr

iTrader: (1)

106 are pretty likely to be causing detonation too, go to a 104 if using autolite.

lt1 power

i beleive it is 233 239 duration cam, and i was thinking the same thing the plugs may be too hot 104s would prob work better.