245/40-17 would yield shorter gearing than 255/40-17.

 

Ah HA!! For the smaller/local venues, that would be a big help.... Heck, I didn't reach the rev. limiter at Nats, so it might be helpful there too. Then again, I was slow... Maybe the other faster AP1 folk were on the limiter.

Thanks for explainin' it to me.

-Dave

 

Interesting! Looks like the difference may be minimal though ... would you notice it on course in 2nd? Wonder what the weight difference is?

245/40ZR17 24.7(dia) 9.8(width) 9.1(tread width) 840(revs/mile) (weight?)
255/40ZR17 25.0(dia) 10.2(width) 9.0(tread width) 830(revs/mile) 26lbs

The Hoosier A6s 245 vs 275 is a 1" difference in diameter. That equates to a 2-3mph difference according to data logs from last year. If the tire works better for the S2000, none of this will matter anyways.

-Marc

 

Interesting.

 

Yes, this is definitely not a huge gain or anything, but it helps out the gearing of the overgeared AP1. 1 mph may not sound like a lot, but remember, it's moves the sweet spot of our engine's peaky powerband. Other benefits include a slight natural lowering of the car, being able to slightly lower it more, a slight (.3 lbs) weight reduction, slightly more responsive tires. All of this, and no drawbacks, if their info is indeed correct.

I like "free" performance upgrades

James Yom

 

These cars flat-out rule in STR trim. I loved my 2 years on the sticky Hoosiers in A Stock, but the change to STR just turned the fun factor knob up to 11.

Today's event, my fastest run and event FTD: http://www.youtube.com/watch?v=DA4z60v2vyQ
Wild bumps around at 0:13, 0:36, and 0:41. The section at 0:41 felt crazy in the car but 0:13 looks worse in the video! I think I know why I have more tire rub issues than most here... I run 10mm bumpstop packers on stock-length shocks and bumpstops to keep the front tires out of the fenders.

Yeah, major brain fart at 0:55! I just kept the clutch in and coasted to the corner. Doh.

 

I would agree with turning up the fun factor knob to 11 relative to STR. I am happy that I spent the first five years running stock class so that driving was the priority, but now setting up the car is half the fun.

Fun video. I may have to get one of those DL1s.

 

Here's a video from yesterday on a very fun and challenging course. If you cannot down shift in an S2000 you are screwed, especially an AP1.

Sept 19, 2010 - Fastest Raw Time 66.2 sec +1 at Marana Airport, Tucson, AZ

Course map, runs clockwise.

 

^ Very nice!... BTW how are you all determining when to downshift and when not to

 

I'm sorry to pollute this thread with my newbness, but I'm looking at an '01 S2000 that I want to run in STR. I ran my RX8 in STX until I had to get rid of it.

Anyway, while I'm sure this info is already buried in this thread someplace, I have to make a decision about the car today in order to book my flight and pick it up this weekend.

Does the '01 AP1 have any significant disadvantages when compared to other years or the AP2?

What are the pluses and negatives about the '01 vs. the other years in terms of tire width accommodation (with or without rolling), aftermarket support, ECU tuning, and any other mods that would be legal in the ST class?

Again, sorry about posting about topics that I know have been covered, but I'm under the gun on time. A link to an FAQ or SCCA resource is welcome!