The thing that bothers me is that you can buy a set of expensive tires and there is no information on what tire pressure to use to get the optimal performace out of the tire.

So this is limited to high performance tires good for up to 200mph, no 60 series BFG tires just ZR rated and above.

Alright the poll didn't work, just list your tires and the tire pressure in this thread and a reason if you want.

 

You have been on this site long enough to know you will get answers all over the place. For me I live in the Northeast with lots of bad roads.
BFGoodrich G-Force Sport Com-2 Summer Only 255/45x17 30PSI, for better handling would raise to 35 PSI

 

Goodyear Eagle F1 Asymmetric 2
255/45-18 running 33PSI.

Seems to be wearing well.

 

Nitto NT555's at 32 PSI seem to be the best compromise......

Jebby

 

I just put 4 new Cooper Cobra's on my 81. I am running them at 30 PSI. they seem to be fine.

 

I've gone through many sets of W and Y rated tires over the years on my Vette and other vehicles i own. I get the best symmetrical ware with Nitrogen running 6-8 psi less than the max tire rated pressure of 51 psi.

That is on my Nissan SUV, 2001 firebird, and 79 Vette. My Vette has wide tires, getting the rears for even tread depth ware is something you ahve to keep on top of. Radial tires leak over time and I do jack the car up to relieve the springs and tires over the winter.

 

I run 30 cold in all my cars from a 61 to a new 2016 Z06. It just seems to be the sweet spot for both performance and tire wear. By the time the tires warm up in the summer, they will get to about 36.

 

BFG'S work for me

 

I own a few cars...and they all have ZR tires (W/Y's) ultra high performance summer only and ultra high performance all seasons including my DD's.

78 Vette-255/45/17 ZR Kuhmo ECSTA-ultra high performance summer only- 35 PSI
2008 Chrysler 300-245/55/18-Cooper RS3-A (all season)-35 PSI
94 Mustang GT Convertible-245/45/17-Cooper RS-3 (Ultra high Performance Summer Only)-40 PSI
2001 Pontiac Grand Prix-225/55/16-Cooper RS3-A- 35 PSI

I generally run 35-40 PSI with ultra high performance tires..AND usually get 40,000+ miles out of each of them...C6Z06 excluded

 

255/50r17 nitto invos, 32psi. Started up higher initially, but any higher than that is brutally rough on some of the pot holed country roads (highish speed limits) around my house. I have fairly stiff suspension (factory gymkhana with just over a coil removed in the front and ~1.5" removed from the rear leaf, bilstein sports all round). At 36psi, it was just unbearable over rough roads at 80+km/h (50+mph), and I have always driven cars with stiff suspension. I also seem to have fairly consistent temps across the tyre at this pressure, but haven't driven it enough to determine tyre wear yet.

Edit: Should note that is cold pressure. Rises 4-6 psi when hot.

 

I generally rely on the tire mfgr's and tire shop to help me know what the cold pressure is on Any of my vehicles..
You ask them and tell them what your primary driving is and the weight of the car and they will know..
Caveat..makes a huge difference to have steering, alignment etc all up to spec..Any tire will wear poorly if misapplied to a vehicle whose alignment or suspension are not right..

Add to this having a loose "nut" behind the wheel or on the gas pedal..and things can go south for performance-longevity fast.

I run current BFG radials.255/60 R15 RWL on my '78..Same size that came on the car when new only current generation..

Where I live and drive..tho they ARE speed rated above 100 mph.....I never drive the car much in excess of the max speed of 70mph here in the Pacific Northwest..Jim

 

My apologies to the OP...as he's running hotter than I ever will..The BFG's are working great for me and my humble driving needs..
.I'm not certain why anyone running even a modified C3 would need 200 mph rated tires..but suppose there's some reason..Jim
#

 

I run 35 PSI even on my daily driver which has 45 series 17s on it.
I don't think you could go wrong choosing in the range of 32 to 35 PSI.

 

I have addressed this question before on many other threads, but will attempt a short answer here since you asked. Tires are not all round and black. There are big differences in the impact that tires can have on the suspension of any car, old or new. ZR tires are really not about the actual speed rating since most people do not drive over 100+ mph on the street. What the speed rating does tell you is much about the tire's capabilities to reject heat build up, the tire's construction (MUCH stronger carcass and much stiffer sidewall preventing sidewall flex), grip level in the dry and wet, and something not apparent, the ride capabilities of the tire. A ZR tire will run MUCH cooler than a S rated tire like the S rated BFG 255/60/15, is a MUCH stronger tire carcass than the S rated tire, uses softer rubber than the rock hard S rated tire greatly enhancing the cars handling in the dry and wet as well as braking ability, AND will offer a superior ride to the BFG 255/60/15. When I switched from the BFG 255/60/15's on my 78 to the current 255/45/17 ultra high performance summer only tires, the difference in all these characteristics to the S rated tire was unbelievable and the reason I use ZR tires on my 190,000 mile 2001 Pontiac Grand prix since day 1 it was new....I can assure you using these tires has nothing to do with their 168 MPH speed rating since the car has no where near that top speed capability. Heck, you can buy a chevy cruze that comes with V/Z tires in the sport versions....for all these reasons.

 

Same here on my 72 but inflated to 35.

 

Thanks to OP for his definitive rely to my Q about why 200 mph speed rating..I'm not certain the cost difference subtle changes to ride would even be noticeable for me..Jim

 

I thought that I would try something new on my Nissan cross over AWD suv. Maybe get a MPG more. They a AA traction and temp rated. V speed of 149. I've never been over 100 mph and the nissan seems to like 80 -85 right at what the freeways are posted.

To be green they use higher tire pressure to decrease rolling resistance. When I brought them I wrongly trusted the tire store to correctly inflate them. Like monkeys they inflated them to the door sticker even though these were wider and lower aspect ratio with a max psi of 51. Just driving home it seem to wallow and unresponsive steering. I checked the pressure and they were @32 psi. So I went back and had them filled to 44 psi with Nitrogen. It was what they needed. Now 40,000 miles later they are getting low on tread depth.

Continental - PureContact with EcoPlus Technology

The PureContact with EcoPlus Technology is Continental's Grand Touring All-Season tire developed for the drivers of luxury performance sedans, sporty coupes and crossover vehicles. PureContact tires are designed to balance long wear, a comfortable ride and low rolling resistance with wet grip and all-season traction, even in light snow.

Featuring a silica-enhanced, all-season tread compound, the PureContact with EcoPlus Technology incorporates Continental's Tg-F Polymers and +Silane additives to improve treadwear, fuel efficiency and traction on slippery roads. The compound is molded into a computer-optimized asymmetric tread design that reduces pattern noise while chamfered tread block edges enhance dry-road handling. Independent tread blocks are siped to provide additional biting edges while Continental's Traction Grooves (vertical ridges in the circumferential grooves) promote three-dimensional snow-to-snow traction.

 

Lots of good info here, glad it wasn't a poll. I bought TOYO T1R's for my Vette a few years ago, still plenty of tread. They were filled with nitrogen and pretty sure I told them to fill them to 32psi even though it was a tire and wheel shop.

So it seems my 32psi is somewhere in the middle. One thing that surprised me and touched on above was the lower profile tires had a much softer ride than the BFG's I took off. The other was the handling which made it feel like it was on rails around a corner.

As for the speed rating that is taken care of above by jb78L-82. However I did have my rear tires up to 186mph on a chassis dyno, and I am over the speed rating of the BFG's on the dragstip