Changing Gears...

[67rally]

I'm thinking about changing the differential gears in my '67 Camaro this winter and would like to hear your suggestions.

I just did a 6.0 LQ9/GTO T56 swap last spring. I did a heads/cam/intake build, 458rwhp/410ftlb. It has an Edelbrock Vic Jr. Intake, so it really likes to wind up, but with the current gearing it feels like a bit of a dog off the line. It's rev limited to 6800rpm. The rear is a '67 12 bolt posi with 3.31's. I'm running a 26.7" street tire (275/40/18). The car will see very little/if any strip time. Mostly street, not a daily driver, plan to do a few Auto-X's with it though.



The GTO T56 is geared as follows: 2.97, 2.07, 1.43, 1.00, .84, .57. Combined with my 3.31's that gives me a 1st gear final drive ratio of 9.83.

Originally I was thinking 3.73's or 3.90's. But I drove my wife's Audi S5 over the weekend and it rips off the line. From what I could find, her diff gearing is 3.89 and her trans gearing is as follows: 3.67, 2.05, 1.46, 1.13, .92, .78. Giving her a first gear final drive ratio of 14.28.

Now I'm leaning towards 4.10's, 4.30's, maybe 4.56's? Any thoughts? (Not that I'm ever going to race her, but I'm putting out almost 200hp more than her, and would hate to get eaten up from a stoplight).

[67rally]

Also, 6th gear is currently useless. I think I'm turning 2000-2200rpm at 90mph.

[astroracer]

Depends on how drivable you want it to be. How does it hook with the street tires and 3.31's? Does the Audi have traction control? That will make a big difference. I have an '02 Collector Edition T/A with LT headers, SLP air box and smooth bellows with a dyno tune after I put in a set of 3.73's. With the Traction Control on it down right ****s and gits but, with it off, it is a wheel spinning SOB. I am running 285/30-18's on it and with no, TC they may as well be 225's.
Mark

[67rally]

The Camaro hooks well with the 3.31's. If I need to go to a stickier tire with shorter gears, I'm fine with that.

The S5 is AWD, so that's a huge advantage. I'm not really worried about competing with the Audi, I just liked the gearing better so used it as an example.

[67rally]

Can a mod can move this to a section that gets a little more traffic? Like a general performance section? Thanks.