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Would this help?

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Old 08-21-2016, 07:09 AM
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Car: 1986 Pontiac Firebird s/e
Engine: 305 Chevy
Transmission: 700r4
Axle/Gears: 2.77 for now
Would this help?

Sirs,
I have a 1986 Firebird s/e that I brought off of an old lady 130k, with the Lg4 305. I installed a Comp Cam 260 H cam, and started it up. Of course, I expected to run with a lope , and it popped a check engine light. I was wondering if switching to a L69 computer of the same year would help adapt the car to aftermarket cam. I am planning on a few standard mods as well, long tube headers, and new 3" single exhaust, and I do already have an Edelbrock performer intake on her as well. The stock Lg4 cam had 179 duration @ .050s, and this Comp Cam has 212 @ .050s.
I'm trying to have this car running with NO check engine lights, so I can sell it quick.
Old 08-21-2016, 09:49 AM
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naf
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Re: Would this help?

Originally Posted by w41duvernay
I'm trying to have this car running with NO check engine lights, so I can sell it quick.
Put the original cam back in?
Old 08-21-2016, 10:03 AM
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Car: 86 Trans Am WS6
Engine: 383 stroker
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Re: Would this help?

the ecm isn't going to see what it wants to see with that cam, you're better off ditching the ecm and going with a non ecm controlled carb
Old 08-21-2016, 10:26 AM
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Re: Would this help?

Originally Posted by naf
Put the original cam back in?

Old 08-21-2016, 11:40 AM
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Car: 1986 Pontiac Firebird s/e
Engine: 305 Chevy
Transmission: 700r4
Axle/Gears: 2.77 for now
Re: Would this help?

Originally Posted by naf
Put the original cam back in?
Naf,
I don't know what happened to peanut cam. It's gone. I want to try to go to a mid 80's HO ecm.
Old 08-21-2016, 02:11 PM
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Axle/Gears: 3.27/3.70 borg warner 9 bolt
Re: Would this help?

Well what code did it send? You may need the ECM tuned.
Old 08-21-2016, 05:28 PM
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Re: Would this help?

Originally Posted by TylerSteez
the ecm isn't going to see what it wants to see with that cam, you're better off ditching the ecm and going with a non ecm controlled carb
I agree, and it will make much more power.
Old 08-21-2016, 10:34 PM
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Car: 1986 Pontiac Firebird s/e
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Axle/Gears: 2.77 for now
Re: Would this help?

I've ordered a L69 ecu from another 1986 Camaro. Since the cam timing on the L69 engines are only 10 degrees less than the Comp 260H cams, I'm going to try that first. I'm going to the shop and readjust the valves to make sure all of the valves have been properly done. My pop thinks that may have been a problem.
Give me a couple of weeks on this one guys. I let you know what is going on.




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