I have my choice of 225/40/17 and 225/45/17 Hoosier R6's (non-staggered) for track (NASA TT). Not sure order next. I've been using the 45's for the past year since that's closer to stock. I like them, but I'm wondering if the gearing change with 40's would be helpful. Anyone have experience?

 

I'd say it's advantage or disadvantage would be track dependent. The shorter tire will give you slightly more acceleration in a given gear, but you would reach redline at a lower speed. It's like getting a slightly shorter rear end, the 3.6% difference in tire diameter equates to a rear end ratio of ~4.25.

If you are just reaching the rev limiter at the end of the straight with the 45 tires, you would mostly likely have to shift again or ride the rev limiter with the 40 tires, which may slow you down. The flip side of that is also true, you may be able gain time by using the full rev range in a given gear when before you weren't.

Take a look at the tracks you run at and see if you would benefit from such a change. It may help on some and hurt on others.

Aaron was running 225/40-17 A6s on his old s2000 with success in the Midwest/Great Lakes region.

 

Hi Pat,

For what it's worth, I would have loved to have the slight gearing advantage at Putnam this weekend - For me, 4th gear was just barely dropping me out of VTEC. 225/40 would have helped a lot over the 255/40 I was running.

Aaron did say he thought the 225/40 A6 tire was the fastest tire he's run on the S2000, not sure if that is due just to the A6 compound, or a combination of the size and compound.

I think it would have been helpful at Autobahn too. You can watch Aaron's video and see where he shifts. If I recall, the only place that was questionable was between turns 3 and 4, where he was bouncing off the limiter, but kept it in 4th gear for turn 4.

 

There would also be a very slight advantage to using a shorter tire because it will lower the car and reduce the drag.

 

Interesting. I'm bouncing off the limiter at Autobahn south with the raised redline - so I think a shorter gear would be helpful. Should carry me through "patience" faster and, even though it's an added shift, it's probably a needed one. Plus, I coming out with a shorter gear sounds beneficial as well. I think it would help on the back straight at Gingerman, but I'm not sure about the front straight. I think I'll give it a try.

Jason - did you ever figure out what transmission you had? Stock final drive right?

 

Yeah, Aaron said it is the AP2 transmission. The final drive is stock as far as I know.

So are the final drive ratios/differential ratios the same between the AP1 and AP2's

 

Hey Jason, it's Derek. AP1s and AP2s have the same 4.1 final drive ratio (in the diff). The gearing difference is all in the gearbox.

 

Hi Derek, thanks for the clarification.

Your AP1 vs mine seem so much different in shifting locations. Odd that after making the AP2 torque-ier with a lower redline that Honda also geared it lower. I guess they were gunning for fast acceleration numbers..?

Pat - yeah give it a try next year! All the cool kids will be doing it. I'm hoping that the A6 will work pretty well in the very cool temperatures we get for the first couple events of the year.