Is there an aftermarket contraption that y'all possess that would allow me to reduce my highway cruising rpm? I'm told differetial gears are the way to go. i've searched the internet and came up with nil. thanks.

 

The mew MR with 6 speed would take care of that !

 

It sure would except I have a 5 speed. A new transmission and swap would cost how much? 4-5k+? I don't want to spend that much bling.

 

Junk yard wreck?

 

Unfortunately, the MR 6 speed and GSR 5 speed both share virtually the same top gear.

GSR box:
1: 2.928:1
2: 1.950:1
3: 1.407:1
4: 1.031:1
5: 0.720:1
Final drive: 4.529:1

MR Box:
1: 2.91
2: 1.94
3: 1.43
4: 1.10
5: 0.87
6: 0.69
Final drive: 4.582:1

As you can see, they share virtually the same top gear (0.72 vs. 0.69), but the slight difference in final drive makes it about even.

In order to drop the highway cruise rpm, you can change the mainshaft in the gearbox to something lower, like a 4.11. I believe HKS or JUN offers something to this effect or perhaps try calling Sheperd Racing. Last I spoke with them, they said they could do a 4.11. This will basically make acceleration less violent, but allow you to gain more mph in all gears. Don't feel like doing the calculations again, but I think it makes 5th gear stretch to 200+mph.

 

How much does a custom mainshaft cost?