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BlackMK4
Aug 23, 2006

wat.
Megamarm
The door jamb tire pressure is for the OE tires, not that I am saying that they are right about the sidewall pressure

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BlackMK4
Aug 23, 2006

wat.
Megamarm

JQADDINGMACHINE posted:

Yes i might have worded it poorly, I meant they think the sidewall is the correct pressure when it isn't and complain about the dealerships setting pressure "low" at only 36psi or whatever.

Totally, sorry, I wasn't trying to call you out, I was just throwing a thought out

BlackMK4
Aug 23, 2006

wat.
Megamarm
Tires are incredibly difficult to compare when they are close unless you are literally hot swapping between brand new sets on the same car on the same day and have data to base a conclusion off of. It is easy to call a set of tires poo poo when you're replacing an unevenly and heat cycled set out for a brand new set of a different brand.

BlackMK4
Aug 23, 2006

wat.
Megamarm
RE71R will last nowhere near that and cost much more, but you already know that. What kind of car is it?

BlackMK4
Aug 23, 2006

wat.
Megamarm
In addition to what Jamal mentioned, maybe the Maxxis VR1 or RT615K+. The normal NT01/RC1 suck in the rain and the RE71R/A052 wears very fast.

I've heard good things about the Federal he mentioned

BlackMK4
Aug 23, 2006

wat.
Megamarm
Once you're into the <=200TW area the ratings are all bullshit and just done to check a box for classing in certain orgs, it annoys me.

The kings of bullshit are the SC3R at 100tw and the A052 at 200tw, both are way outside of the normal window.

BlackMK4
Aug 23, 2006

wat.
Megamarm
Grassroots Motorsports is for you then :) They focus on 200tw tires, and mostly ones that come in 15".

You can usually get a pre-read on stuff like that if you visit the right forums and listen to what people like Andy Hollis have to say.

BlackMK4
Aug 23, 2006

wat.
Megamarm
Additionally, listed tread width and treadwear are bullshit for <=200tw tires so it might not be a stretch anyway

BlackMK4
Aug 23, 2006

wat.
Megamarm
I assume you mean +22 and +26 for offset. 22 - 15 = effective +7

You'd need an offset of -5 to match your 20" wheels, so you more or less need a 30mm spacer with the 19" wheels.

https://www.willtheyfit.com/ is your friend. Subtract your spacer size from the wheel offset to get your effective offset.

BlackMK4
Aug 23, 2006

wat.
Megamarm
Way too many variables to answer that.

BlackMK4
Aug 23, 2006

wat.
Megamarm
Swap the wheels side to side and you'll have your answer

fwiw, i've noticed the brz is extremely sensitive to rear tires and causing pulling left on throttle / right lifting throttle

BlackMK4 fucked around with this message at 00:44 on Dec 27, 2021

BlackMK4
Aug 23, 2006

wat.
Megamarm
RT660 is a much faster tire than the RT615K+ and will also live a much shorter life.

In terms of tracking them, the RT660 kind of has a reputation right now for coming apart. Just run the 615K+ unless you're competing.

BlackMK4
Aug 23, 2006

wat.
Megamarm
It is fine other than not working properly in the wet.

BlackMK4
Aug 23, 2006

wat.
Megamarm
Someone finally did official testing on tire width vs wheel width... matches up with what 949 Emilio / Andy Hollis have been saying for like a decade. Maybe now the stigma towards a non bubbled sidewall can die

https://www.tirerack.com/tires/tests/testDisplay.jsp?ttid=296

quote:

Summary
So what did we learn? The key takeaways are that in the dry, a wider tire does not automatically mean faster lap times. Using a wheel width that properly supports the tire will provide faster laps than a wider tire with very little wheel support. We saw this in our testing - the 215/45R17 tire on the 9" wide wheel was noticeably faster than the much wider 245/40R17 tire on the 7" wide wheel. That's not to say tire width doesn't matter, though, as the 225/45R17 combinations were all faster than the 215/45R17s. The 245/40R17 on the 9" wide wheel was very close to the 225/45R17 on the same wheel. If we could fit a 10" wheel width on our test cars, the pattern seems to indicate a 245 on a 10" would have been the fastest combination of all.

In the wet, a narrower tire is generally faster than a wide one, and once again, more support from the wheel is better. The 215s on the 8s and 215s on the 9s were the fastest combinations in the wet. The 215s on 7s, 225s on 8s, and 225s on 9s were a step back from there, and all the 245s, along with the 225s on 7s, set the slowest wet laps of the test.

BlackMK4
Aug 23, 2006

wat.
Megamarm

devicenull posted:

I should bring this in and insist they patch it right



lmao. My condolences

BlackMK4
Aug 23, 2006

wat.
Megamarm
Costco had a sale on Bridgestone RE71RS, finally time to try a quicker tire after running Toyo RRs and Maxxis RC1s exclusively for the past five years of track days.

BlackMK4
Aug 23, 2006

wat.
Megamarm

Imperador do Brasil posted:

My 911’s extra wheel set have RE-71RS’s mounted on them and I can’t wait til spring to run them.

Yesss, I've heard nothing but good things. I'll see how they do for me in a few weeks.

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BlackMK4
Aug 23, 2006

wat.
Megamarm
This is an example of why I have trust issues with tire sizes. I run my car in a series that uses a tire template gauge for tire width legality due to advertised tire sizing being BS.

This is a 257mm tire template moved all the way left on a 255/40/17 Maxxis RC1 on a 9.5" wheel, which is a DOT legal competition tire that runs fairly wide compared to most 255 tires. Easily a third or half and inch of clearance on the tire gauge, as to be expected.



Had a set of 255/40/17 Bridgestone RE71RS mounted to another set of the same 17x9.5" wheels today.




It is the exact limit and likely won't clear as the tire wears since it already touches the sidewall when pushed onto the tread, which is convenient since the rule is that you can bring a new tire mounted on the same size wheel if you fail the go-no-go test.

Also, the 200tw RE71RS is a faster tire than the 100tw RC1.

Guess I get to carry an extra new tire with me to events.

BlackMK4 fucked around with this message at 21:20 on Dec 29, 2023

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