I just bought a solid 69 SS clone, with a 454, TH350 three speed, 12 bolt posi 3.73 rear end. Just starting to enjoy the car, but want to add an overdrive to make it more enjoyable at 55 mph +. Any recommendations on whether to look to add an overdrive or to replace with a newer beefed up 700R? I have not decided if I will keep the 454 or not, some have said to make it more desireable for resale, a 502 is the way to go.

Any advise on transmission or engine replacement?

Thanks
Ron

It all depends on the power level of Your motor. Adding a O.D. transmission would be the way to go, but You could also install some 3:08's to settle down the cruise RPM's. There are several different avenue's, but I wouldn't replace a good 454 with a 502 just for resale.

I would recommend an overdrive tranny over adding an overdrive to your current tranny such as a Gear Vendor. They are extremely well made but the one I had was only 22% overdrive which didn`t help as much as I had hoped. Went to a 5 speed Tremec with 36%, helped a lot. Go with a 700R4 and leave the 3.73 gears I think you`ll have a blast with it.

Sid