Hello, I have a 65 Valiant with a newly rebuilt 225. The engine is runs strong but about 60 mph is as fast as the car wants to go without feeling like i'm pushing it to hard. It has the 904 trans.
My question is, could it be the gears in the rear end? Could I replace them with taller gears to be able to drive a little more comfortably on the freeway? Any help would be great. Thanks

sfellon@keyway.net

It sounds like you might have 3.55 or even 3.91. I had almost the same problem with my old 66 /6 truck. If I remember correctly the guy at the diff shop said I had 4.88 and the truck sounded really!! wound up at 55mph(topped out at 60, but could cruise 4 gear at 25 easy). I put 3.91 in it and it helped alot, 65 is still pushing it though.
Well I may not have helped much but it sounds like your on the right track. Good luck.


andyman225_99@yahoo.com

Go and check the ratio, the number is stamped on the edge of the ring gear, under the rear cover. The ratio is also stamped on the outside of the center section, usually on the drivers side "cross-rib". (a gussit going from the center section to the "leg")

When all else fails, spin one wheel around 2 times, (the other wheel held solid, like on the ground) and count the turns of the diff. yoke. My bet is it will go around 3 1/4 turns which would be a 3.23 ratio. Let us know what you find.

If it is not the gear ratio, no strong high RPM "pull" could be caused by no spark advance or a lean main jet in the carb.
DD