Watch the TPC code for replacement tires

[Throat Yogurt]

Since we’re on the subject of tires anyone size up from OEM? My last car I was able to get a little better straight line traction without any rubbing by going up to 305’s instead of 295’s in the rear

After driving the car at Spring Mountain, I'm not changing a f***ing thing. The handling balance is perfect.

 

[theprototype]

After driving the car at Spring Mountain, I'm not changing a f***ing thing. The handling balance is perfect.

Lol I feel ya, but here's the rub (pun intended) - I ain't taking any turns at 50+ mph like I did in Spring Mountain out here in the real world. So for me I'd rather have more rubber contacting the ground for that straight line traction because let's face it, I floor this thing from a stop every day but I won't be tracking it for a while (if ever).

 

[Throat Yogurt]

Lol I feel ya, but here's the rub (pun intended) - I ain't taking any turns at 50+ mph like I did in Spring Mountain out here in the real world. So for me I'd rather have more rubber contacting the ground for that straight line traction because let's face it, I floor this thing from a stop every day but I won't be tracking it for a while (if ever).

Striaght line traction is definitely more of an issue for you in the 5 than me in the 4!

 

[MatthewAMEL]

It's not just the size. While the TPC PS4S is good, it's hard pressed to handle the straight line acceleration and the 275 up front can't stop all the understeer.

On the OEM wheel, The Falken RT660 is avail. It's an EXCELLENT dry grip tire.

According to Apex, you can get a 20" on F/R and then the Goodyear Supercar3 in 285/305 is available. Also an excellent tire. On the 20", you can also get the GY SC3R...arguably the best 100TW track tire. Again, 285/305.

Haven't seen anyone get a >305 on the rear yet.

 

[theprototype]

It's not just the size. While the TPC PS4S is good, it's hard pressed to handle the straight line acceleration and the 275 up front can't stop all the understeer.

On the OEM wheel, The Falken RT660 is avail. It's an EXCELLENT dry grip tire.

According to Apex, you can get a 20" on F/R and then the Goodyear Supercar3 in 285/305 is available. Also an excellent tire. On the 20", you can also get the GY SC3R...arguably the best 100TW track tire. Again, 285/305.

Haven't seen anyone get a >305 on the rear yet.

Yeah, if I go 315 in the back I would definitely be shooting for a 285 in the front. Another benefit to sizing up is the tire fills the wheel well a teensy bit better and to my untrained eye adds to the aggressive look.

 

[Andi]

Happens on every car forum. I’ll never understand why people are intent on taking such an amazing piece of engineering and making it worse.

Stock handling balance is amazing and the custom spec tires are a big part of that. My advice is DFIU.

 

[99sport]

On the OEM wheel, The Falken RT660 is avail. It's an EXCELLENT dry grip tire.

When the Falken 615s came out they owned the street tire (non racing slick) class in autocross for several years. Other manufacturers finally matched them, but the 660s are currently very competitive in autocross where maximum grip (not heat resistance) is paramount.

Grassrootsmotorsports does multiple tire tests per year (whenever a promising tire is released) and the Falkens are near the top of their testing. I don't remember them testing the PS4S and certainly not the TPC ones.

My guess is the Falkens would overheat on a 4200lb car on a fast racetrack in short order (fast autocross tires often get cooled with water after a 60 second lap to maintain their grip), but I do think they might be promising for regular street driving.

I'm sure the Cadillac engineers choose the best tire available for a wide range of requirements (low noise, great ride, ability to do track days for multiple hours, good wet and dry grip, etc), but if your only requirement is dry grip I do wonder if the Falkens would be better.

Someone in Florida (where Grassrootsmotorsports is based) should volunteer their blackwing for a tire test

 

[Daijoubu]

Since we’re on the subject of tires anyone size up from OEM? My last car I was able to get a little better straight line traction without any rubbing by going up to 305’s instead of 295’s in the rear

 

[Throat Yogurt]

When the Falken 615s came out they owned the street tire (non racing slick) class in autocross for several years. Other manufacturers finally matched them, but the 660s are currently very competitive in autocross where maximum grip (not heat resistance) is paramount.

Grassrootsmotorsports does multiple tire tests per year (whenever a promising tire is released) and the Falkens are near the top of their testing. I don't remember them testing the PS4S and certainly not the TPC ones.

My guess is the Falkens would overheat on a 4200lb car on a fast racetrack in short order (fast autocross tires often get cooled with water after a 60 second lap to maintain their grip), but I do think they might be promising for regular street driving.

I'm sure the Cadillac engineers choose the best tire available for a wide range of requirements (low noise, great ride, ability to do track days for multiple hours, good wet and dry grip, etc), but if your only requirement is dry grip I do wonder if the Falkens would be better.

Someone in Florida (where Grassrootsmotorsports is based) should volunteer their blackwing for a tire test

Yeah, I used to autox on Falkens back in the day and those things would overheat like a MFer to the point where you had to spray them down with water between runs.

 

[99sport]

Ultimate track tire guide | 200tw, 100tw, street-legal track, R-comp

In this tire buyer's guide, we cover 200tw, 100tw, street-legal track and R-comp tires.

grassrootsmotorsports.com

I'm not sure how the TPC varies from the regular 4S, but based on the table below, the Falken should lap a track faster, but the 4S destroys it in wear / longevity (which you'd expect from a factory tire) and also wet traction.

2022 Cadillac CT5-V Blackwing at Lightning Lap 2022

The apex predator is still a contender for quickest four-door. Maybe next time.

www.caranddriver.com

"Even if the Cadillac had turned that time, it would not be enough to beat the new Lightning Lap four-door king, the Porsche Panamera Turbo S. To do that, Cadillac would have to mount an even grippier tire. A Pilot Sport Cup 2 R could be the way to take the throne. There's only one way to find out, Cadillac."

 

[MatthewAMEL]

It's about time we had a tire thread!

RE: the RT660...I have run them since they were announced. They are top-tier AutoX tire and an even better track tire. They handle heat very well. Far, far better than the RE-71, A052 or RivalS.

I ran multiple sets for years on my SS 1LE which is a 3,800lb car and set PB at every track I ran with them.

BTW - At my 1st Time Trial with the Blackwing, part of the tech process is to weigh the car. Mine (BW5, M6) weighed 3990. These cars aren't as heavy as you would think.

GRM typically only tests 200TW tires. Occasionally, they will do a 100TW test. I often run with them at the FIRM (where they perform their tests). I can ask if they have done any PS4S testing next time I see them.

As for the differences in TPC versions and non-TPC...this video does a great job of explaining.

 

[MatthewAMEL]

Oh. And the PSS5 is on the way?

Yup. Michelin Pilot Sport S5 is launching this summer. OEM for first year. Benefits include the same construction as TPC/*-spec in the Retail version.

They changed the naming convention again. It’s not the PS5S…it’s the Pilot Sport S 5. PSS5.

 

[sethsquire]

GM did it.

The 5.3L V8 FWD LS cars of about 2008. That would be the Impala SS, Grand Prix GXP and Monte Carlo SS.

Excellent bit of trivia right there. I remembered that about the tires on the GXP, but not the other two

 

[MDM]

The 5 definitely needs much more traction to make 1st gear actually usable. I'm thinking some Mickey Thompson or Nitto drag radials would make it really fun.

 

[strohw]

The TPC front is on back order still. I ordered a set from Tire Rack about 10 days ago and they still haven't got any in stock. Usually they have an estimate but they don't have one as of now. Driving around on winters still.

 

[Daijoubu]

The TPC front is on back order still. I ordered a set from Tire Rack about 10 days ago and they still haven't got any in stock. Usually they have an estimate but they don't have one as of now. Driving around on winters still.

Weirdly, I ordered a full set back in September from Tirerack, and they finally arrived in January. Rears were in stock, they were waiting on fronts to send them all together. When I got them, though the date codes on the fronts were way older (I think December 2021) than the rears (October 2022). So, the tires seem to be out there somewhere. Next time, I'm going to check with the dealer first.

 

[LongGrayLine16]

better straight line traction without any rubbing by going up to 305’s instead of 295’s in the rear

As physics has taught us, traction is not a result of the tire's width. Traction is a result of the tire's compound and the coefficient of friction. Softer tires mean higher coefficient of friction - leads to better grip.

Wider tires allows for a greater contact patch (surface area). Greater surface area means that you can run softer tires and still support the weight of the car without failing.

Wider tires in the SAME TW mean they will theoretically last longer because the wear over time is distributed over a larger surface area.

But, yes, a wider tire sounds cooler when you tell your buddies about how thicc she is

 

[dstewart51]

Time for tires, cant find the TPC spec for the front locally, dont have time to wait for the TPC spec tires to come in so going to have to put a set of aftermarket PS4S's. I'm sure the new aftermarket 4s's will still feel better than the old warn out OEM's.

 

[BimmerFan]

Time for tires, cant find the TPC spec for the front locally, dont have time to wait for the TPC spec tires to come in so going to have to put a set of aftermarket PS4S's. I'm sure the new aftermarket 4s's will still feel better than the old warn out OEM's.

View attachment 21722

How in the world did you do that to the inside of the tire? You've either got some alignment issues or some very aggressively configured camber plates.

Happens on every car forum. I’ll never understand why people are intent on taking such an amazing piece of engineering and making it worse.

Stock handling balance is amazing and the custom spec tires are a big part of that. My advice is DFIU.

OMG, ain't that de truth bruh! These guys (and gals) think that they are better engineers than the folks at GM/Ford/Porsche/BMW etc. Sure, everything is a compromise of price/performance/longevity but let's not mess it all up. They generally know what they are doing, especially on their performance cars.

Of course, I'm not referring to you fellas here, just everyone else.

 

[RDATLTE]

Time for tires, cant find the TPC spec for the front locally, dont have time to wait for the TPC spec tires to come in so going to have to put a set of aftermarket PS4S's. I'm sure the new aftermarket 4s's will still feel better than the old warn out OEM's.

View attachment 21722

Damn, that's a lot of tread left for them to chord on the inside like that.