jyalpert
Member
Yeah, probably not much, especially given the lack of camber adjustability. Though I would really love to see someone do a ridiculous widebody RocketBunny Tesla.
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Best Tires/Wheels for Tracking Model 3
- Thread starter kbecks13
- Start date
SammichLover
Banned
If you ever want to hook your Model 3 up with some of the purple crack, that'll have to happen. No Hoosiers within weight specs for the Model 3 until somewhere above 300.
beastmode13
Member
jyalpert
Member
I corded the outer edge of 3 of 4 4S tires in 4 track days with the factory alignment at 36 psi cold.(~44 psi hot.) More negative camber was definitely needed and the pressures were too low. The tires were rolling onto the sidewall. Ambient temperature was around 70 deg F.
With the RE71-4 I started at 40 psi (~50psi hot) still need more negative camber but have more even wear after 2 days. The tire wear was pushing just to the arrows. Ambient temperature was around 90 deg F.
The MPP rear camber arms (and toe?) are looking like an imperative to help the tires wear more evenly and allow one to drop the pressures. Hopefully it's easy to adjust between street and track settings.
With the RE71-4 I started at 40 psi (~50psi hot) still need more negative camber but have more even wear after 2 days. The tire wear was pushing just to the arrows. Ambient temperature was around 90 deg F.
The MPP rear camber arms (and toe?) are looking like an imperative to help the tires wear more evenly and allow one to drop the pressures. Hopefully it's easy to adjust between street and track settings.
jyalpert
Member
Just another data point. At stock pressure (42psi cold), I did the same to all 4 tires in 2 track days.
Same location, Saturday I used 37psi and Sunday I used 39psi for one sessions and then switched back to 37psi. Wear pattern on the tires looks odd to my eyes. I'll post a picture if I get some time and remember.
I like 275/35/19 on the P3D. Apart from being wider, they're actually closer to the stock diameter than the 265/35/19's are (3mm taller vs. 5mm shorter). Being taller also helps with the top end in theory, but 3mm is likely negligible. Another small bonus, 275 width on a 9.5" wheel means you're more protected from curb rash as the rubber protrudes 3-4mm past the edge of the wheel.
275's can work up front, but it's close enough that some tires might not work depending on how square/rounded the sidewall shape is.
Below is a picture of the front suspension clearance on my 275 PS4S's on 19x9.5" +40 wheels and a 3mm spacer. I think a 10 inch wheel would need +33 or less offset to make it work. It's very close.
Debating on a second set of 17-18lb 19x9.5" wheels and 275/35 RE-71R's for track-only use in the future if I end up getting more competitive.
275's can work up front, but it's close enough that some tires might not work depending on how square/rounded the sidewall shape is.
Below is a picture of the front suspension clearance on my 275 PS4S's on 19x9.5" +40 wheels and a 3mm spacer. I think a 10 inch wheel would need +33 or less offset to make it work. It's very close.
Debating on a second set of 17-18lb 19x9.5" wheels and 275/35 RE-71R's for track-only use in the future if I end up getting more competitive.
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beastmode13
Member
beastmode13
Member
That seems high.
There is a thread about Randy Pobst at Tesla Corsa 3, he asked the pressure to be set at 28psi on the RE71R. Of course, Randy is Randy.
Lol yes he did, and we didn't believe him! Ended up lowering them quite a bit during the day to stay under 40 hot BUT my car has camber arms installed and about -1.8 degrees of camber dialed in, so that helps prevent the sidewall rolling situation.
I know this is a 3 thread...but i just got a set of Yoko A052 255, 20" for my P85 and they are pretty damn close to RE71R (not sure about wear yet)....I was only .25 seconds off top time in our autocross and took PAX by >100pts!!! just slayed it this weekend...soo close to beating a fully prepped SMF Civic DX with a fast driver!
I run about 38 PSI warm for any set of 200 TW
I run about 38 PSI warm for any set of 200 TW
jyalpert
Member
Typical target pressure on the RE71R is somewhere in the 32-35 range. I'd guess something like 50psi is due to a combination of not nearly enough negative camber + too narrow a tire, requiring ungodly pressures to keep from destroying the shoulder.
Would be very interested to see some pyrometer readings across the tread, as well as someone chalking the sidewalls to see what portion of the tread is being used. There is likely a LOT more grip available from dialing this in.
Tire Pressures - Finding the Sweet Spot
jyalpert
Member
Alignment is pretty much S stock ~2 degree toe in on rear (not sure you can change an S too much with out other links?). I have a square set up now for proper F street. Fronts wear on the outside, rears on the inside & rotating keeps them wearing smooth across the entire tread until they become complete slicks before cording.
the 255 yoko have more tread contact than the RE71 & on the 20" they bulge a little more where the RE71 look better fit on the sidewall. seems to work well. really don;t know what is faster. our course was set up pretty quick. The Vette in AS was ~.5 behind me and I have never been so close in time to the Civic driver in any of his prepped cars so I feel that the AO52 may be faster or pretty equal in auto X
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jyalpert
Member
Nice!
Does the Model 3 dynamically toe out at the rear under compression? Could probably reduce inner shoulder wear with something closer to 0 toe, but then risk an unpredictably loose rear end (like the S2000)?
It certainly is crazy high pressure but that's what was required due to the lack of negative camber. I'm sure there would be GOBS of grip by installing the MPP camber arms, lowering the pressure, and increasing the negative camber - hopefully to something between -2 and -3 deg. That said the car was easily manageable and lots of fun even with the street alignment. I am planning on starting around 32psi with negative camber and see how it goes. (I used to run 30 psi front, 32 psi rear in another car with -3 deg front and rear.)
P.S. I've done so many track weekends I don't know how many it's been. I stopped counting around 100 days on track. Haha, that makes it sound like I have a problem.
Agreed, it would be close with the RE71-R. The RE71-R 275/35R19 has a 10" tread width. The Pilot Sport 4S 275/35R19 has a 9.8" tread width. The +40mm wheels on a P3D with 3mm more rotor and 3mm spacer compared to the P3D+ +35mm wheels have 1mm more of clearance on the inside.
The stock diameter tires are as follows:
334mm (18") - 790 revs / mi
335mm (19") - 787 revs / mi
336mm (20") - 786 revs / mi
The RE71-R specs are as follows:
265/35R19 - 791 revs / mi
275/35R20 - 784 revs / mi
So they're both really close but the 265/35 actually match very very closely to the 18" wheels. I suspect that we should lie and choose the closest diameter when calibrating the TPMS as I don't know why else the car cares about the wheel size.
While I didn't chalk there is no doubt where the tires were being worn after a 20 - 30 minute session.