4.10 Or 4.30 Gears In 8" Rear?
 

I GOT A 67 COUPE THAT I'M GOING TO BE BUILDING VERY SOON!

I WOULD LIKE TO KNOW WHICH GEARS WOULD BE THE MOST BENEFICIAL TO ME.

I PLAN ON USING A C4 TRANS WITH A SHIFT KIT AND 2800-3000 STAHL CONVERTER.

A 289 BORED 0.30 OVER AND A LUNATI CAM WITH .512" LIFT.

WHICH GEAR RATIO WOULD HELP ME THE MOST 4.10 OR 4.30?


THANKS FOR THE HELP!

It really depends on what you're going to use the car for. If you want it to be a driver for the street, I wouldn't put anything over 3.55 gears. 4.10 or 4.30 gears will cause the engine to really wind at highway speeds. You'll hate it if you try to take the car on a long trip. But, if you're going to take the car to the track a lot, the lower gears would help.

3.55:1 rear gears with a 25" tall rear tire will result in a 3,000 rpm cruise @ 60 mph with a C-4 or 4 speed for that matter! 4.10:1 will result in a 3,800 rpm @60 mph!!! Unless you can spin that baby to 8,000 rpm forget about doing 120 mph down the highway!

If you're going to go all out with the motor and the trans, ditch the 8-inch rear go with the 9-inch. You'll spend all that money putting the rear together just to shatter it when you get a hard launch.

I've never heard of anyone tearing up an 8" rearend. I had one for years with a 351CJ in front of it and didn't have any problems. But, I think that they usually are more expensive than 9" rearends. Changing out a center section in an 8" rearend can cost $700-$800. It might be cheaper to replace the whole axle with a 9".