The biggest con to Pontiac motors is the cost of building a high performance one. Parts are more expensive and Pontiac basically didn't make very many high performance engines you can use as a base to start with.
Pontiac motors aren't that heavy. They weight more than a SBC, but less than a BBC. Add headers and an aluminum intake and you are probably on par with the weignt of a stock SBC with iron intake and exhaust manifolds.
I know what you mean about making the late 80s early 90s F-bodys fast. I think that is why there aren't that many fast ones around. You could probably build your Pontiac motor for the same price as fixing up your current car and retaining the ability to pass a smog check.
On Pontiac motors: they are torque monsters. Pontiac made big heavy cars and the motors were designed accordingly. The intake ports on the heads were designed to flow very well at low RPMs. The standard heads run out breath after 5,000 RPMs. As a result, the rest of the engine was designed to run under 5K. The crank is cast steel (not bad) and the rods were cast steel (bad). A stock 2-bolt bottom end is good to a little over 6,000 RPMs if you use aftermarket forged rods. However, you need better heads to do it.
The best Pontiac heads are the Ram Air III and IV heads. They a very expensive - about $1,000 for a set that needs to be rebuilt. Edelbrock makes a good set of aluminum heads that are patterned after the Ram Air IV heads. I would go that route if you have the money. Add the cost of a rebuild and some porting to the price of the Pontiac heads and you will easily hit the $1,800 price tag of the Edelbrock heads.
The only issue I see is that the 80 T/A would also have smog requirements, unless its exempted somehow. It would have a smog pump, catalytic converters, and all that stuff.
I am currently helping a friend with not so good mechanical abilities fix up his '72 Firebird. He insisted on using a Pontiac motor, so I have had to do a little research. E-mail me if you are interested in more info. We found several good sources of info for properly building a good Pontiac motor.
Pearl blue & white 69 Camaro with supercharged 350, Tremec TKO, and 3.73 12-bolt
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