68Supreme

i have an origonal 68 Supreme w/ a 350 rocket. Car runs and drives perfectly for being a 68 " its like butter". I am comtemplating rebuilding the motor, even though it runs fine. I would just like more power to the wheels.

opinons from the pros; should i rebuild storke my origonal 350 with all matching numbers? or just pick up a spare block. If i bore my origonal block does my ride lose a lot of its value?

help me out, im torn

Oldsguy

Welcome to our site. If you car is numbers matching already and you want to keep it that way then acquire another engine and rebuild it. When it is ready, switch them out and store the original. To be honest though, unless your car had a convertible top, a four speed with a bench seat, or some other very rare option it won't be that much of a collector's item even though we all value our Oldsmobiles very much. As far as how to rebuild it or how far to go, I don't think you need to stroke the engine. The classic formula of a little more aggressive camshaft with valve train parts, aftermarket manifold and carburetor, headers to dual exhuasts and a freshened up tranny would do the trick. Oh, and simply re-boring the cylinders is really just maintenance if you do it to the original block but don't do it unless it needs it.

2blu442

I know it's a personal preference, but I'm a sucker for the big blocks. A 425 or 455 will give you more grunt, and would be an easy swap. Years ago I rebuilt a 1970 455 with a better cam, intake and carb. I ran it in a 1971 Cutlass Supreme with 2.56 rear end gears. Then later I pulled that engine to put it in my 1970 442 and replaced it with a 1968 350 already rebuilt, so I'm not sure what was in it but the idle was smooth. The two engines pulled hard to about 50 mph, then the 350 started to level off. The 455 continuned to push me back in the seat well past the 80 mph mark, which is as fast as I drove it in normal driving conditions, passing someone. That's my experience with a mild build on each for good driveability. John

68Supreme

Thanks for the feed back, i guess my Olds is not special enough to view as a collectors item. oh well she's still mine, I'll probably just rebuild my 350 if it gives me any problems, but for now she rides like butta

Redog

I nice way to go, if you want more power, I would go to Mondellotwister.com and buy myself a new set of forged flat top pistons. Be sure that you get the right size, if you're getting it boared out a bit.

These pistons will increase compression, how much depends on cc of your heads. If you have the 5 heads, Stainlees valves, 1.6 or 1.7 rockers, new springs, longer pushrods, tied all together with a nice cam from Mondello (jm 18-20 or JM 20-22) will make a nice amount of power. Don't forget the Intake manifold, re-jetted q-jet or a new carb, and maybe a nice set of headers followed up by a decent dual exhaust, will make a decent amount of power.

There are a couple of little things you can get too, but also don't over look a 4 speed tranny instead of the 3 speed and a higher ratio rear end set up

68Supreme

with the set up you speak of, what are the possible power ranges i could pull from my existing motor? oh and i have a 2 sp so may be in the market for another tranny soon.