Randy Pobst Twitter Today

[BmacIL]

I honestly don’t think people here understand that when you get to these crazy amounts of power how the increase grip from one tire such as the 4S makes so much of a difference when you go to an R compound. That R compound Allows for much later breaking, more lateral G and speed through corners and quicker for Full throttle acceleration out of it. The other parts of the CFTP Package no question work and have an impact, however their affect is dramatically decreased without the grip provided by the R compound.

It was said best earlier: you could throw the CFTP aero, minimal spring rate increase, magneride and abs tuning at the base car, and it would have nowhere near the pace of the CFTP car. The tires actually allow for a lot of that stuff to make a significant difference.

Some of you people need to take a basic physics course with a supplement of Caroll Smith.

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[Trackaholic]

From what I’ve seen over the years, as a rule of thumb, switching from street to R-comp tires is worth roughly 1 second per mile.

-T

 

[Droopy1592]

another Good example ‘16 350R ran a 1:36.11 at Laguna Seca, now I couldn’t find a ‘16 350 but Maybe someone else has it or knows? They made some tweaks to areo and suspension and added SC2 tires and the ‘19 350 ran a 1:36.83!! Now obviously there complete tuning for the added grip helped but that’s gotta say something about the tire.

I already posted about this a couple of pages back. There were calibration and aero changes of all sorts, adjustments to the suspension, and I know from paying attention for 30+ years, Michelin rarely stands still on tire tech. There are often year to year minor improvements even on the same model. Run a updated R with the changes and new tires and it will probably be even faster. Not much, but probably faster than 1:36.11.

 

[Droopy1592]

You’re right, they are not totally linear nor did I ever say that. However we aren’t comparing different vehicles here with different characteristics, we are simply comparing tires. And there’s a much closer relationship there. For example the 1LE at the ring is 13.6 seconds faster on the 12.9 mile circuit than the ZL1. At VIR 4.1 miles 4.4 seconds 1LE faster. Totally different tracks yet very similar differences. I imagine the GT500 will have very similar differences from track to track.
You could individually swap the wing/suspension/weight reduction or tires. None well reduce the base (w/tp) like the tires. Now if I was a full on track rat (not the 2-3 a year I currently do) I’d go all in on the complete package for sure.
Is there any data on the wing where the additional downforce really comes into play? I know a lot of times the speeds have to be much higher then we typically see to get the true benefit. I’d be very curious to see what kind of gains the CF wheels provide, my thought is they mostly relate to a better feel, and response not necessarily much lap time increase. But I’d love to see some data on that if anyone has ever done it seen data on it.

no, you didn’t say it directly, but your math clearly implies it. I’m sure I could run through data and find tracks where it’s not proportional (time and distance deltas). We just have to wait and see.

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