1981 Pontiac Firebird horse power and what size engine?

1981 PONTIAC FIREBIRD

81TRANSAM

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Engine Performance problem
1981 Pontiac Firebird V8 Automatic ... miles

hi, i have a 350,The engine was bored .40 over with flat top pistion installed. what would the size of the engine will be (like a 400? that was a example.) also it has a edelbrock intake and edelbrock 650 carb. dynomax headers. what would the horsepower be at with all that done with the car..

Nov 18, 2008 at 10:27 PM

KEVIN12881

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is that the origanal engine? I thought that year had a 4.9L with 210 horsepower. Anyways you will be lucky if you can get 250 to 275 horses out of that engine, though you could hit much more if you spend the money. I have a 95 trans am with an LT1 and it only came with 275 from the factory and after more than 3k in add ons (one a raptor trans---no help in horse but help in loss), i will be lucky if i hit 300. I have a new elderbrock exhaust, cold air intake, new throtle body, new pc, good plugs and wires, and trans

Nov 23, 2008 at 8:44 AM

KEVIN12881

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you are going in the rght direction, maybe you are even at that 275 mark, but remember what you get off the crank has nothing to do with what you put to the ground!!

Nov 23, 2008 at 8:48 AM

81TRANSAM

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thanks for ur car talk.. i recently bought the car, so im tryin to find more about it. it does look like there was more done to do it, but i have to get ahold the guy who sold it to me, i can get pics if anyone would like to see the engine so there just not staring at a wall i can do that..

Nov 23, 2008 at 10:28 AM

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