SCCA Solo C Street Discussion

[Cueman]

Regarding tire pressures, I'm curious what others are using with 245 RE71's.

I finally ditched my Star Specs and picked up a set. 225 would have been preferred, but a local vendor had a screaming deal on 245's.

Tire pressures...
I have a pyrometer, so at the first event was checking temperatures, and letting them tell me what they can about what pressures to run. The surface was well worn asphalt. Not that grippy. Ambient temperature about 70 degrees.

Rear: I started at 35 psi, and bled all the way down to 27psi before getting nice even temperatures run after run. The tires were still not rolling over to the triangles.

Front: I started at 38 and bled all the way down to 31 before roll over became an issue. Temperatures said the center of the tire was still getting over worked. I wanted to bleed down more.

As for speed and feel. My co-driver and I definitely felt like the car was more sloppy feeling with less pressure... but speed seemed alright, and I thought the car got more friendly on the edge. We didn't quite PAX where we had hoped to on the new rubber, but were pretty close.

What is everyone else on 245's using for pressures? I'm thinking I might throw a couple more pounds in next time, just because 31/27 seems really low.

[Locust]

If you guys had to guess at it... what do you think the time difference is between factory alignment and -1.5 camber front, -1.0 rear on a 60 second course?

Originally Posted by Cueman

Regarding tire pressures, I'm curious what others are using with 245 RE71's.

I finally ditched my Star Specs and picked up a set. 225 would have been preferred, but a local vendor had a screaming deal on 245's.

Tire pressures...
I have a pyrometer, so at the first event was checking temperatures, and letting them tell me what they can about what pressures to run. The surface was well worn asphalt. Not that grippy. Ambient temperature about 70 degrees.

Rear: I started at 35 psi, and bled all the way down to 27psi before getting nice even temperatures run after run. The tires were still not rolling over to the triangles.

Front: I started at 38 and bled all the way down to 31 before roll over became an issue. Temperatures said the center of the tire was still getting over worked. I wanted to bleed down more.

As for speed and feel. My co-driver and I definitely felt like the car was more sloppy feeling with less pressure... but speed seemed alright, and I thought the car got more friendly on the edge. We didn't quite PAX where we had hoped to on the new rubber, but were pretty close.

What is everyone else on 245's using for pressures? I'm thinking I might throw a couple more pounds in next time, just because 31/27 seems really low.

I run 29 front, 27 rear on 225s. It wasn't even close to the triangle on the sidewall until I did that. The stupid TPMS warning light comes on but at least it's a good reminder to put air back in after I'm done racing. 31/27 isn't "really low" if that's what works.

[Biggins]

I've regularly run 31f, 27-28r on 235/45 and 225/45. It works, but do what's comfortable for your driving style/pavement.

My local lot was just resealed, so I ran 28f, 25r to compensate and it was okay. No one was fast, but I was on par with where I usually am...

[renfield90]

Originally Posted by Cueman

Regarding tire pressures, I'm curious what others are using with 245 RE71's.

I finally ditched my Star Specs and picked up a set. 225 would have been preferred, but a local vendor had a screaming deal on 245's.

Tire pressures...
I have a pyrometer, so at the first event was checking temperatures, and letting them tell me what they can about what pressures to run. The surface was well worn asphalt. Not that grippy. Ambient temperature about 70 degrees.

Rear: I started at 35 psi, and bled all the way down to 27psi before getting nice even temperatures run after run. The tires were still not rolling over to the triangles.

Front: I started at 38 and bled all the way down to 31 before roll over became an issue. Temperatures said the center of the tire was still getting over worked. I wanted to bleed down more.

As for speed and feel. My co-driver and I definitely felt like the car was more sloppy feeling with less pressure... but speed seemed alright, and I thought the car got more friendly on the edge. We didn't quite PAX where we had hoped to on the new rubber, but were pretty close.

What is everyone else on 245's using for pressures? I'm thinking I might throw a couple more pounds in next time, just because 31/27 seems really low.

FWIW the magazines ended up with low pressures as well (30-31 or so). You are probably on your own with pressures - I don't know anyone else in a twin running the 245 stones.

Also with the 245 pinched on a 7" wheel, accept the fact that you're going to murder your tread shoulders.

[anonymoustallguy]

Originally Posted by renfield90

FWIW the magazines ended up with low pressures as well (30-31 or so). You are probably on your own with pressures - I don't know anyone else in a twin running the 245 stones.

Also with the 245 pinched on a 7" wheel, accept the fact that you're going to murder your tread shoulders.

Interesting. I thought there were others. Tires look like they will be dead in three events... not sure the shoulders are going to matter. The center rib shows major major wear after only 12 runs.

[renfield90]

Originally Posted by anonymoustallguy

Interesting. I thought there were others. Tires look like they will be dead in three events... not sure the shoulders are going to matter. The center rib shows major major wear after only 12 runs.

Those who have worn through the center rib that fast either have too high a pressure, less than ideal driving style, or frequently run at a very abrasive site. There are people with 100+ runs on their stones with very reasonable wear.

Assuming you stick around 31psi and don't run at an abrasive site, try using less slip angle - not intending to criticize, but you may be overdriving the tire without realizing it. The RE-71R doesn't like a lot of slip angle anyways.

[Cueman]

weird... looks like I have a forgotten account on my wife's computer.

Criticism welcome. I registered for the Packwood Tour and Pro, which will be the first event where I get to run against other twins. Expecting to get humbled. Hopefully will learn a bunch.

[SeanRTR]

Originally Posted by anonymoustallguy

Interesting. I thought there were others. Tires look like they will be dead in three events... not sure the shoulders are going to matter. The center rib shows major major wear after only 12 runs.

The center rib on the RE71R wears very fast on the first couple of events.....


it seems to stabilize after that though, as I have several runs, and several thousand street miles on mine, and they're actually holding up alright. I still prefer last years tires though, as they actually require half a brain to drive fast.

[Jawnathin]

Originally Posted by SeanRTR

I still prefer last years tires though, as they actually require half a brain to drive fast.

On RE71s you can get away with WAYYYYYY more stuff than you could on something like an RS3 or Z2. You can be very hamfisted, throw it around and save it relatively easily. It really is an easy button to go fast.

[coneracer30]

Since we are talking about tire wear. Here are my Rival S's after 156 runs on course asphalt (Packwood and PIR). They were flipped after 70. Not too bad.

[bslate3]

What is everyone using for brake pads? I'd like just a little more bite and heat tolerance now that the Texas summer is in full swing.

[renfield90]

Originally Posted by coneracer30

Since we are talking about tire wear. Here are my Rival S's after 156 runs on course asphalt (Packwood and PIR). They were flipped after 70. Not too bad.

How is grip at this point?

Seems pretty reasonable to me. I'm expecting to flip around 80 runs.

[SVLTE]

Wow, someone else is actually running the rival S? So little love for the tire compared to the 71R. Running 225 or 245? I'm on 225's and have been curious what others are running for pressures. I knew it didn't have a sidewall as stiff as the stones, but I've found mine to need pressures at or north of 35f/33r

[TMF]

Originally Posted by bslate3

What is everyone using for brake pads? I'd like just a little more bite and heat tolerance now that the Texas summer is in full swing.

I just bought the HP+, but I literally just picked up the car on Monday and haven't installed them yet. I'd be curious to hear what others are using also. Due to the lighter weight of the car, I'm wondering if the HP+ will be too much?