Question: what is the best Trans & Dif gear selection?

[Jester]

I thought it is worth getting some opinions from the roadster experts regarding the best transmission gearing and differential gearing selection for combination performance, street and longer hwy cruising. I use the car for spirited driving and hwy cruising. I have a tko 600 with an .82 fifth gear and a moser rear with a 3.31. powered by a Coyote. The car seems to perform very well and cruising at 75 mpg - revs at ~ 2500 rpm. I assume this is typical. I plan to drive as is for the upcoming season and I may change the gearing to lower the rpm in 5th gear

I would like to know if this gearing set-up is typical - best for my application.

[Jester]

I have reviewed many of the posts on the other forum on this topic and it seems as though the 0.82 fifth gear with a 3.31 rear is very common and often recommended (or similar gear ratio) as it results in a cruising speed of 70 mph @ ~ 2500 rpm vs the 0.64 fifth gear at 2500 rpm for ~90 mph. Many comments that the 0.64 fifth gear requires very high hwy speeds and many engines bog down in 5th at lower rpm requiring a down shift to 4th. I have also seen several posts that some owners have changed out the 0.64 gear for the 0.82 gear to get a more useable 5th gear.

After further thought, I think the 0.82 5th gear is the correct choice.

[Avalanche325]

The combination you have is probably one of the most common for an all around car. I have the same thing with a 347.

[Jester]

The combination you have is probably one of the most common for an all around car. I have the same thing with a 347.

Ok - thanks for confirming