a9l with 30lbs inj

[rawdog94]

i have a 302 with track heat intake, comp 282 cam, 65mm tb, 75mm mass air meter 30lbs inj, elderbrok heads p/p and a 9al computer. what do i need to do to make it idle correct? all it does is surge. i also have msd 6al box. please help.

 

[Paul]

Do you have a tune?

 

[SnakedMark8]

You are dealing with few things here. For one and I've posted this several times before; the so called calibrated MAFs are rarely calibrated correctly. The ones that are close will get you decent results but that's about it. There is no real repeatability with these and they do tend to cycle or move from one spectrum to another. Basically they fool the EEC into thinking there is less air coming in and so the EEC backs down the pulse width of the injectors. Problem is that this also throws off the load calculations which then throws off the spark and fuel tables beside shift programming with autos. The only real and correct way to calibrate for different injectors is through the EEC. Now you can have that MAF installed and have the vehicle dyno tuned to get the a/f corrected and if they know what they are doing they can rescale the MAF to get your load where it should be. That's one problem.

The second is also common; you need the EEC recalibrated for the increased air flow. Larger intake and mostly larger cams will cause the surging idle if the calibration isn't adjusted for this. Once again a dyno tune to correct it or a good tuner with experience dealing with this that can set you up with a mail order tune.