Pro-M 75mm with stock Meter = engine kaboom!

Boss 351

Here sthhhhhhhheeeve take a picthh of my man flowe
Jul 13, 2003
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Canada
Well I have a Pro-M calibrated for 24lb injectors, Cobra intake, 24lb injectors, 70mm Throttle body, 1.7 rockers, and AFR 165 heads. Saving up to buy a tweecer, wideband O2 sensor, and a new 95GT computer (I have a 92 Cougar, not a Mustang). I want to have the entire setup calibrated properly from A to Z... Afterbuying these parts, I wish I would have swapped over to carb, but it's too late now... Stupid EFI bullcrap! :(

Of course so far, nothing is installed, I even have the paper air filter. But I wanted to see what happens when I upgrade my 55mmm MAF housing with the larger one, however using the stock meter. I think I felt a small difference (very little, can't hardly tell it's there - could be in my head) in the upper RPM, no change in the lower. The engine idles great, good throttle responce (better than before), doesn't ping (currently has cheap 89 octane fuel)...

I was warned that this will kill the engine? So I did some searching and read this: http://www.allfordmustangs.com/Detailed/583.shtml From what I gather I could be causing a lean condition with this new "setup". I will run the car for a week like this and constantly check the spark plugs for sings of a lean condition. So far, I did not notice any change from stock. Not that it really matters, I'm just really curious about this now :nonono: :shrug: Sometimes my curious nature gets the best of me. I'm learning this EFI stuff.
 
Seems like your project has risk and no reward, why bother.
And why would you use a 95 mustang computer? Not nearly as good as the foxbody computers.
 
The A9L (which I do have in stock) won't work with the MN12. The more I learn about this stuff... the more I want to buy an old carb'd car :lol: