Editing the Constants (Scalars)

Hello all,
I need to start editing the constants (scalars) for:

1)The Pro Comp Cam # 07-305-8....not sure where this is

2) Long tube headers....not sure where this is/does this even need to be edited?

3)Bored 0.030 over..... i am looking at the "cylinder volume" and it is currently @ 717.25 ml/cyl. is this ok? or at what # does it need to be?

4)Bosch 3 injectors/24 lb./PN FIC24TPI.... on the "injector flow rate" it is currently @ 24.87lb/hr( i believe this is ok?)


5) Gears > 3:08.... not sure where this is

6) Tire size > 17 in ....not sure where this is

Wondering if someone can point me in the right direction to the correct constant(?) to make these adjustments.

PCM 16188051

thank you

The gear ratio and the tire size affect the speed sensor pulses per mile. Did you change gear ratio or tire size? Are you using a different pcm? If not then you probably don't need to change these values.


Cylinder volume is equal to the engine displacement in liters *.008. For a 350 that's bored .030" the calculated number is 727.41.

Bosch injector flow looks ok. There are other injector numbers related to low voltage and small pulse widths that may need changing.

Constants are single numbers, like cylinder volume. There is no single constant for the cam or headers. Cam and headers affect the volumetric efficiency and they affect spark timing. For these adjustments you'll need a way to log data so you can review how the engine is running to make changes. I know of no other method without very expensive simulation software.

The LT1 w/4L60E is in an 84' El camino, it came out of a 94"Caprice. with the 3:08 i will be running 235/60/17's. The Cam timing is too much for me to handle, so i will be going with PCMPERFORMANCE OR Moehorsepower. i'll get the gear,tire size, cylinder volume etc, done with them too, along with adjusting for my shift kit. I'm kind of ok with simple On/off stuff, but when it comes to mutiple adjustments (like how you are explaining) to compensate for other modifications, I'm not up to that kind of experience.

Out of curiosity, have you successfully flashed a tune into the PCM? That's something that I have no experience with and that's where I'm reluctant to offer assistance due to all the bricking stories. Have you tried the xls spreadsheet to calculate PPM, tire size and gear ratio located here:http://www.gearhead-efi.com/Fuel-Inj...ull=1#post2958 Can't remember from your other post, I thought you were able to log data...it's purdy much give the engine what it wants i.e. +- fuel +- spark for starters. Are those listed places on the mainland or are they local? BSM Performance was the only place that I knew of that does this sort of tuning but I don't know what happen to Bode's business. The new owner's that took over Bode's shop I think they specialize in the newer stuff.