I know a few of the folks here are autocrossing the RX8 on Hoosier 275/35-18's and am wondering how many runs on average you are getting before cording these tires. I'm trying to estimate my tire budget for next season. Thanks.

 

Well, that's an interesting question.....

So far, we have noticed the following (275/35/18 A3SO4's and 275/35/18 R3SO4's):

The autocross compound wears quickly at first (2/32" gone the first day), then start to settle in to a slightly better wear pattern after the first couple of heat cycles. Ours quit being effective after about 25 runs, but have yet to wear out (100+ runs), but we can go faster on our set of roadrace compound than the autocross compound after about 25 runs.

The roadrace set has about 75-80 runs on them, and are about a half second slower than new. The dropoff in performance has been gradual, and not nearly as much as the autocrossers. Also, the roadrace compound wore quickly initially, but after a couple of heat cycles have settled down. I can tell they are (also) losing grip, but it doesn't look like they will EVER wear out on their own!

So, if you are planning on waiting until they are corded, buy the roadrace compound and run the entire season (unless you run national events, then buy a new set of autocrossers for every event) - with the proper pressures and driving style, you should be fine. We ran all of 04 on one set of autocross and one set of roadrace compound.

 

Thanks Tim. I do usually run the west coast tours and pros though its been a few years since I've run more than one pro in a season. I'm trying to decide whether I want to run B Stock or set the car up for STU. Its seems like it may end up being cheaper to run STU despite the initial setup costs.

OT, I notice you have photos of the racing beat and borla exhausts on your site. Which do you prefer?

Thanks, Tom Smith

 

The Borla sounds a little better (I think) and is lighter, but it was annoying to have to loosen and retighten all the "slip" joints on the system every couple of autocrosses to stop it from rattling on the heat shield.

The Racing Beat sounds WAY better than stock, and best I can tell it's a couple of pounds heavier than the stock system, but the quality of build is second to none. I'm keeping it.

 

***cough***waitforthe710***cough*** :p

Hi Tom!

 

Anyone tried the dB's on an open exhaust?

 

I think Racing Beat tried one and said it actually hurt their ears - maybe poke around on their website or give them a call. I'm thinking the TI is the way to go, but the manufacturers aren't any I've heard of. Anyone else?

 

I couldn't help myself and cranked her up when I removed the cat.

oh my...

 

Tom/Keith - I was talking to Brian Goodwin today by e-mail and it sounds like there may be a few more exhast systems in the works, which hopefully will be available in the next few months. From the sounds of it, it may be worth waiting for...

 

an unfettered rotary is something you dont want to hear too much of. why are they so loud? and the sound is especially grating.

has anyone had success with the treatments like formula V on heat cycled/hard tires?

sure hope the 710's stay fast longer than 25 runs... ouch.

james

 

LOL

 

LOL

Hi Annie!

I know and am waiting for the 710 but who knows when our sizes will arrive and who knows when non-contract drivers will get some.

I'll probably start the season with R3S04's.

As for the Borla exhaust slip joints, I would just tack weld them after everything is in place.

Tom

 

I could care less about the sound it makes as long as it's under a certain dB at a certain amount of feet. Sure, the quieter the better for a good neighbor policy at tracks, but when it comes down to brass tacks... weight is weight.

If it's 'loud and grating enough' that's fantastic for ProSolo starts... if you can get your competitor at the line distraced by your sound... all the better. :D (ie: the 1st time I lined up with Jr. Johnson with my new at the time exhuast on my Subaru... he actually looked over and shouted something.... couldn't hear a word!) We came back in and he mentioned something about 'that sound came from a Subaru?' It was a good enough distracton if you can unsettle Jr.

There's more to an exhaust than having 'just the right sound' to me. I could care less how obnoxious it is as long as it's legal.

--kC

 

>here's more to an exhaust than having 'just the right sound' to me. I could care less how
>obnoxious it is as long as it's legal.

hehe, i guess i am still suffering from when i modified my rx7 along those lines. guess im getting old.

i like loud- my autocross car sets off car alarms when i drive by :D its just the rotary has a sound like a saw cutting through the bone in your head. but if you are talking cat-back that might pass sound.

james