Next CDC Autox Sunday May 25th at Waldorf

[echan]

The next CDC autocross will be on a SUNday (not the normal day of the week) on May 25th at Regency Furniture Blue Crab Stadium in Waldorf, MD.

Reservations for members and their guests is now open. Non-members can make a reservation starting on Friday May 16th on a first-come first-serve basis.

Hope to see you all there!

Ed

[Nathan Atkins]

Signed up, the wait will be agonizing!

[Jim Harris]

I'm in, in the S2000.

I'm wondering, anybody, what tire index I should claim for the Direzza II. I have been using 101-200 treadwear, but not everyone is. It doesn't seem like a "low performance" street tire to me.

Anybody?

Jim

[echan]

I'm in, in the S2000.

I'm wondering, anybody, what tire index I should claim for the Direzza II. I have been using 101-200 treadwear, but not everyone is. It doesn't seem like a "low performance" street tire to me.

Anybody?

Jim

That is the correct selection. The "low performance" tire is for a standard non-performance/economy/all season tire.

[Areddi]

Ill be on my delayed honeymoon from getting married last fall so I'll miss this one. Very unfortunate cause I have to wait to the end of the season to see what CDC can do with the Blue Crabs lot. Have fun everyone!

[Nathan Atkins]

Haha! Alex loses by default!

[Bondfire]

I won't be able to make it either, have a family Memorial day weekend picnic. Can't believe I have to miss one of the events at this venue!

[aeonracer]

Jim, I never know which HP knockdown to take. I've seen S2000 dynos at 190, and some at 210. I take the high performance street tire 1.0 but then take the 1.1 on power (150-200 at the wheels). Weight is 1.0 as well (2500-3000). If I'm using the wrong index, please let me know.

[Jim Harris]

My impression that our S2000s dyno mostly around 205-210. Assuming 15 percent driveline loss, we come in at 204. So I always select that.

Obviously we're right on the margins, and it could vary from dyno type to dyno type, but that's the breaks.

Jim

[aeonracer]

Either way we should be running the same index, whatever it is. I really don't care and you could probably argue for / against either one.

[glennkrueger]

Jim and Tommy Layton both run the 200-250 HP index for their S2000s. I used to run the 150-200 one because I figured the AP1s dyno right around 200 and mine has a 6-figure odometer reading. But after reading that they use that index, I changed as well.

[Nathan Atkins]

Must be nice having dyno figures that sort of correlate to your actual manufacturer's quoted output!

My car claims 232 at the crank, but they typically dyno at 175-185whp

mine dyno'ed at 154whp

I've seen stock stooks dyno as high as 215whp, but typically just on the high side of 200

[Areddi]

I don't always lost 34% instead of the usual 15% versus power claims, but when I do, because rotary.

[Nathan Atkins]

I'm confident that its still a 15% loss or so, the engine probably produces 200 at the crank give or take, but it lost another 15% due to peacocking bullshit claims that the engine made more power than it did. Mazda always overstate their power figures. They initially quoted 250, then quickly brought it down to 238 after having to return several cars for disappointed customers they then had to revise it again to 232. EPA allows you to quote the actual power value with a 1% tolerance for marketing purposes like a nice round 500 instead of 504 for example. In Britain is quoted as 228bhp, Germany says 231 PS which is also 228bhp.

so if it actually makes 228, that still puts it at 194 to the wheels on a 15% loss which it clearly doesnt make, thats forty more than my car puts down and at least 10 more than average. weaksauce.

But it does speak to the elegance of the chassis that it can go toe to toe with 370Zs with a hundred and some more horses and Twins with similar power but less weight. Double A-arm FTW

No im not bitter at all