1st trip to track, now have gear questions

[fford]

Here is my question, what should I do with the rear gearing?
I have a standard T5 with 3.73 gears out back. 26" diameter ET streets out back. My trap speed was 130.63 @ about 6400 rpm. Problem is the tune is only good to 6000 because I start to float valves, but I had to push it. ET was 11.122 but part of that is due to the FMS clutch slipping, I am upgrading that right now to a spec 3 as soon as I find one!lol
What would I expect from say a 3.55 which I happen to be able to get, I do also still have the stock 2.73 in the garage?

 

[57fairlane]

my vote is for 3.27s . . .

 

[67coupe]

Keeping the tires the same diameter?

What RPM do you want at the finish line?

Assuming 6000rpm and the same 26" tires and a 1:1 4th gear:

3.55 = 131 mph
3.27 = 142 mph