Tire recommendation for HPDE

[Shadow277]

Drag racers go to a staggered setup because they don't need the front tires to do much more than hold the front of the car off the ground.

So with no traction requirements either laterally or for forward acceleration, drag racers tend to go with small tires up front to reduce overall car weight and rotating inertia, and to shift the car's weight distribution a tiny bit rearward. Even if that's only by a quarter of a percentage point (i.e. 53/47 to 52.75/47.25) there's still a little benefit to be had.



If your car has big power or you're driving up near the limits of front tire grip, more than likely yes.

Power sliding is almost never the fast way around a corner and is always a fast way to wear your rear tires out.


Norm

I heard they're fun...

Sponsored

 

[Brian@BMVK]

I assume you are pushing more power?

Wider = more load capacity, which = can lower tire pressures for more contact patch = more grip. Wider tires also have more thermal capacity.

 

[Shadow277]

Wider = more load capacity, which = can lower tire pressures for more contact patch = more grip. Wider tires also have more thermal capacity.

So a bigger tire is always better.

 

[Brian@BMVK]

So a bigger tire is always better.

Most of the time for pure dry lap time. Wider tires also warm-up slower, hydroplane more, tramline worse, have higher rolling resistance and cost more. There's always tradeoffs.

I have done really well on 275 square RE71Rs before. They take almost no time to warm-up and by halfway into a first autocross run, for instance, I had good temperature. The 305 square of the same tire and similar pressures definitely takes more energy to get up to temp, a full run vs half run, unless it's very warm outside.

 

[Vicr]

So in conclusion to the OP's initial question the answer is.....................another rabbit hole to go down? Thank you for those that actually gave us track novices some solid tire recommendations to look at. I too will be taking an 8 hour track class at Pacific Raceway followed up by lapping classes. I'll then be moving to AZ and then on to Wild Horse for track days. Laguna Seca and Willow springs to follow. I'll be retired and have all the time in the world to heat up brakes and wear out tires.

 

[Grintch]

The R-S4 is arguably the best lapping tire you could buy. Durable, tolerant of track heat and loads. Supercar 3 seems to be close, but a little more temp sensitive.

595 RS-Pro are a performance bargain but are missing on some of the subjective aspects compared to the other popular 200TW tires. They also will be a step back on pace for autocross/TT if you care, but then again so will the R-S4.

Don't the Federals limit you to 275? And some lesser known retailers, if you can find them in stock. I also hear they are LOUD even when new. But admittely, any tire that sees much track time tends to get noisy after it gets a certain number of hard heat cycles. But they are one of the cheaper track oriented tires. But they might not be a great choice for a tire that spends most of the time on the street, and only a couple track days a year. More a dedicated tires on a separate set of wheels, but biased to value our max performance application.

 

[Grintch]

Spacers.

Only helps in one direction, and hurts in the other.

As for the you can never have too much tire statement. There are certainly limits, but with a big heavy, power car like ours, bigger tends to be better until you hit the fitment limit. But tire compound and construction usually matters more than size. I am betting 255 Hoosier R7's would beat 305 Cup 2's, much less 200 or 300TW tires.

There are also diminishing returns. For a stockish GT, I think 305s are only marginally better than 285s. And it's a significantly more expensive and finicky setup.

 

[Brian@BMVK]

Don't the Federals limit you to 275? And some lesser known retailers, if you can find them in stock. I also hear they are LOUD even when new. But admittely, any tire that sees much track time tends to get noisy after it gets a certain number of hard heat cycles. But they are one of the cheaper track oriented tires. But they might not be a great choice for a tire that spends most of the time on the street, and only a couple track days a year. More a dedicated tires on a separate set of wheels, but biased to value our max performance application.

The RS-RR are mud tire loud. The RS-Pro are apparently much quieter, perform better. They do max at “275“ but run really wide, like to where they fit best on a 10.5" wheel rather than 9.5-10".

 

[NightmareMoon]

I assume you are pushing more power?

No (not yet), but I do need all the grip I can get.

 

[NightmareMoon]

Only helps in one direction, and hurts in the other.

As for the you can never have too much tire statement. There are certainly limits, but with a big heavy, power car like ours, bigger tends to be better until you hit the fitment limit. But tire compound and construction usually matters more than size. I am betting 255 Hoosier R7's would beat 305 Cup 2's, much less 200 or 300TW tires.

There are also diminishing returns. For a stockish GT, I think 305s are only marginally better than 285s. And it's a significantly more expensive and finicky setup.

255 R7s aside, I completely agree - the 305s are really only marginally better than 285s (with the same tire). I barely noticed any difference at all, but even incremental changes add up. In a non-competition HPDE context, I'd say its not worth it.

 

[EFI]

The RS-RR are mud tire loud. The RS-Pro are apparently much quieter, perform better. They do max at “275“ but run really wide, like to where they fit best on a 10.5" wheel rather than 9.5-10".

They definitely run wide for the rating, but not quite as wide. They fit nicely on a 10" wheel, no pinching like a 295 previous tire did.

They are just about as wide as a 285 Michelin. And can confirm they are much quieter than the RRs.

 

[Brian@BMVK]

There are also diminishing returns. For a stockish GT, I think 305s are only marginally better than 285s. And it's a significantly more expensive and finicky setup.

Can concur, 275/35R19 RE71Rs in 2019 were just as competitive in my hands as 305/30R19 in 2020. There are many other reasons why I wasn't faster last year on an overall setup that should have had measurably higher potential, but mostly it was lack of driver confidence or familiarity in a new and frequently-changing setup. On price, it's really not that much more but takes more work to get fit on the car (extended studs & spacers up front, open lugs, etc).

 

[Norm Peterson]

There are also diminishing returns. For a stockish GT, I think 305s are only marginally better than 285s. And it's a significantly more expensive and finicky setup.

Seems the big advantage to going wider with the tire size comes from the ability to run a slightly softer compound without sacrificing tread life.

Something I copied a while ago from an automotive engineering forum . . .

It says, ultimate grip is proportional to tire width ^0.15, which sounds a bit low to me. So going from a 200 to a 300 mm width tire gives you about 6% more latacc. But you can soften the compound a bit and get some more.

which tells me that going from 285 to 305 in identical compounding is only going to be worth 1%, maybe 2%.

To me, that's something you wouldn't leave on the table in timed competition where you were already competitive . . . something you'd be hard-pressed to notice at HPDE . . . and only good for inflated bragging rights on the street.


Norm

 

[shogun32]

and only good for inflated bragging rights on the street.

but I thought HPDE events were dominated by "look at how wide my tires are" boasts while in the paddock?

 

[EFI]

but I thought HPDE events were dominated by "look at how wide my tires are" boasts while in the paddock?

That and they are also dominated by those jackasses that are trying to set lap records amongst 20 other dudes on the track at the same time, and they won't let any other car get in their way or slow them down in their end goal.

Sponsored