Hey all. I've read some conflicting thoughts on what differential I should be using. I have a early '74 260 that had an auto. I did the conversion to a 4 speed ( I already had one from a 260Z ) The stock diff I believe 3.545 that was being used with the auto is still there. What should or would be best to be using. I'ld rather have more lower end. Thanks ahead of time

Bobby

Stick with the 3.54. It will be a good all-around ratio for a daily driver. A 3.7 or 3.9 would be more performance oriented with a loss in economy. Unless you plan on upgrading the engine I wouldn't persue that option IMHO.

Thanks ezzzzzz I do have some mods. Triple webers, header, Monza exhaust, lite weight flywheel, Centerforce Stage 2 clutch. Daily driver when it's sunny......... No winter use (I'm in the northeast)

Would the scenario change if I also swapped to a 5 speed?

Would the scenario change if I also swapped to a 5 speed?

You could actually go as much as 4.11 with a 5 speed and still have a better overall high gear ratio than you do now with the 4 speed/3.545.

Great wheels/tires , what are you running?

I have a 4.11 R180 w/ the 4 speed. It's great fun from 0 - 60, but it's bad in the highway (3,700 rpms at 65). I have a 5 speed thats going in (again) this Winter that should make the car more "highway driveable".