Phreak's 2016 AutoX Season

[Phreak]

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[Siestarider]

I purchased Joe's pyrometer just so I could relate psi to actual tire temps. Quick summary of my first track day using it, clockwise track, 170's LF 160's RF 150's Rears. Stock suspension and alignment, 215/45/16 Rival S tires 45 psi hot front 43 hot rears. This setup was good for a couple PB's that day.

LF wears fast on that track. I have literally zero experience with tire temps, maybe some more drivers will report pressures and temps and we can sort out what works best.

Re temps, I have to remind myself this car will pull power if temps are excessive, so for track days I quit worrying about it. Or turn the heater on if I can't help worrying.

 

[Phreak]

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[Froctor]

The video was nice to look at. No tire squeal or anything... you're really getting the most out of the car it seems like. I'd love to have some seat time with you and get some tips.

For the tire rollover, maybe you could make the same video but looking at the front tires? Maybe you could see how they react on turns and acceleration? I personally would love to see that.

 

[Phreak]

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[commonplatypus]

Quick question, and I think I've asked you already, but I can't quite recall...

Why did you go with the 205/50 vs the 205/45 RE71? Isn't the compound on the taller tire worse? Is having the slightly taller gearing really that much more advantageous vs the better compound that would be provided by the smaller diameter version of the tire? I understand the 205/50 is also significantly cheaper, as well. I ask because I must soon choose between these two sizes for my own purposes.

 

[Phreak]

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[Phreak]

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[commonplatypus]

There are advantages and disadvantages to both:

Benifits for 205/45:
-Lower center of gravity
-Quicker Acceleration (because it is shorter)
-OEM sizing for the car
-2lbs lighter

Benifits for 205/50:
-50$ cheaper per tire
-Better top end speed (because it is a taller tire)
-About 3/8" wider than the 205/45

For me the price combined with the wider tire made it more attractive. I don't really feel the lighter weight and better acceleration are that noticeable, but the extra grip and top end certainly are for me.

Perfect! Thank you. Do you have any issues with the car coming up on two wheels and "bicycling"? Your Koni Yellow videos didn't suggest as much. I'm kind of nervous about possible rollover issues and I feel like the 205/45 might prevent this because of the lower CoG.

 

[Phreak]

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[commonplatypus]

Holy shit that video is quite frankly a bit terrifying. I'm willing to by your testimony however and believe that the chances of it happening are probably pretty low and that it seems like you get enough awareness of it happening to be able to react to it by turning into the tilt.

Thanks for the well thought out post and info. Do you think there are ways to prevent this from happening aside from choosing different tires from the re71?

Also what do you think the likelihood of the SCCA imposing some sort of regulation or classing restriction against using tires like the re71 are? It is pretty obvious that Bridgestone is not being honest about the treadwear rating on the tire at this point.

Do you think it could be ruled out as an option next year or beyond?

 

[Phreak]

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[Siestarider]

Jim Clark drove a Lotus Ford Cortina at Sebring one year, every time he ran the Esses he put two wheels up at each transition peak. Esses were different then than today's version, exit was just before the old MG bridge. What he did seemed routine for him. My dad pointed it out to me, you had to be in just the right place to watch both sides, front higher than rear, not a lot of air, but seemingly exactly the same every lap. Plenty of drivers raised one front each way, but he is the only one I recall raised both.

 

[RAAMaudio]

I am quite sure I had two feet off the ground quite often at MMP the only time I have tracked this car but likely and it felt like 3 a few times, great fun pounding over the curbs, I am not the smoothest driver nor anywhere near the being called talented but I can make some pretty good lap times but hard on tires and brakes, and engines, and suspension and, everything else....but I build and maintain it and love that part as well

 

[Phreak]

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[Phreak]

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[Siestarider]

Congratulations! The Fist of Autocross strikes again!

 

[Phreak]

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[commonplatypus]

Because of you I finally pulled the trigger on an RE71 and Sparco 16" setup. Very excited to begin applying some of your writing to my autocross runs to see if I can't make a huge improvement in my times!

 

[Phreak]

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