so we have a 65' olds 98. it was custom ordered with ulra-high compression 425 super rocket, pitch slip th400, and 10 bolt posi rear end. the trans just blew out, so we had a racing trans built for it (we know a guy that owns a hotrod shop) and now its in paint. really on that car though, i want to do engine work. stock it has 420HP, and 460TQ!! and i see so many areas that are easily improved. so rite now, i want to machine the heads, replace the intake, get a bigger carb, dual exhaust, cam it, headers (stock manifolds will not work with duals), and upgraded valve train. this isn't going to be all done in one shot, it will be a long process of refining everything, but i wanted to see what everyone thought, and see if anyone had any suggestions. we are going to do the quarter mile some time next weekend, i will post numbers then. based on the eighth mile time it had, before the tune up, oil, new tires, suspension work, and oh yeah, a race trans, we are hopping for mid 11s to high 10s. baseline 1/8 mile was 6.56@78MPH, not warmed up at 6AM, 29 degrees.

 

Ok the 65 98 came standard with a 4bbl 425 engine and single exhaust rated at 360 HP. There was an optional upgrade engine and that was the 425 Sfire engine rated at 370 HP and it had dual exhaust. ALL the 98's came standard with the switch pitch turbo 400 trans. If your car has a posi that would have been optional. Trying to make a heavy luxury car a race piece is difficult. The more your do to increase HP the less fun it is to drive and lives less happier on the street. Many things can be done to that 425 and the choice is yours.

 

im not arguing you, im just replying with info i have been told. i have been told (3 times) that GM had HP limits on their cars. they would say full size cars can only be rated at (X) HP or less for insurance reasons. the manufacturers would go above that, and still under rate it. from what i can tall, torque was pretty spot on though... i was told, by a guy that used to race these cars that it produced a little over 420HP. as far as the pitch slip goes, i know they came with that, i didn't mean for it to sound how it did, and it does have a posi. we have the original receipt to the car, i was just asking how common that option was. as far as not being happy, and being hard to make a race piece, its all ready SERIOUSLY fast, and fun as hell to drive... i am not worried about that going away because it has even more power.

like i said, im not arguing you, im just replying.