tuning for 75# injectors

[camcojb]

I have an 05 GTO with a 402 twin turbo. I'm trying to get the car up and running and of course the stock tune won't run, too rich since the injector is over twice the size. So I found this chart from someone here:

http://www.allmod.net/hpt/injectors.xls

Plugged in my 75# @ 43.5 psi with the GTO's 58 psi fp and transferred the grams/sec numbers into the stock tune. It seemed worse, definitely won't idle.

I now have been told by Ken that GM doesn't allow over 63.5# injectors in their code, so is there something else to tweak to get it right? Also, the engine is a 402, so I'm sure the displacement needs to be changed, I'll need to find that.

Jody

[S2H]

for those others who are looking for info..
to do 75# injectors in an LS2

put these #'s in your injector table..

58.83345    59.19967    59.56395    59.92629    60.28670    60.64420    60.99976    61.35339    61.70507    62.05482    62.40263    62.74851    63.09244    63.43444    63.49257    63.49257    63.49257

then multiply your entire VE by 1.47
same for MAF tables and cranking VE

this should get you in the ball park...

[S2H]

and as far as your displacement question..

((pi/4)*(Bore^2)*(Stroke))*0.0163870641

bore and stroke in inches
0.0163870641 is Cubic Inches into Liters


or the less precise using just generic #'s
(CID/#of Cylinders)*0.0163870641

meaning generic #'s like 346 or 402 or 427 for when you dont have an exact bore and stroke meausrment...but you know what the motot is supposed to be
divide by 8 cylinders and convert to Liters

you may or may not need to scale your VE table accordingly...
I think Keith told me some OS's used it and soem didnt use it in conjunction with VE and MAF...
so from 346 to 402 is an increase of 16ish %

[camcojb]

Thank you very much.

Jody