Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pads

[Bruce H.]

For those that have tracked theirs on the street tire...do they hold up fairly well to track temps without significant chunking, excessive wear, etc? I would think the TA's extra camber would help, nor would I be pushing the car that hard as I will need to drive it home again I should have it on the road early April, 1 or 2 local HPDE to learn the car in May, and then a 3000+ mile road trip in June with 2 track days at both Road Atlanta and then Virginia International. One set of tires needs to go the distance, and I'm sure to run into wet weather driving on road and possibly track where the street tire could be the safer bet. It also seems senseless to wear out a set of Corsas around an HPDE skidpad/track while learning the car, and with endless highway use. If that's the tire I need I could also get the dealer to swap the tires when he gets the car next month before I take delivery so the R-compound Corsas won't be subjected to below freezing temps (my garage isn't heated).

Also, I'm sure to need to change pads after 2 days at Road Atlanta, so I'll need to take spares and tools with me to do that. Which pads have you track rats tried, what's do you recommend based on first hand experience for a car that will see equal street and track use, and is changing the pads a fairly straight forward job on a Viper? I don't expect to want to push the TA too ******* the track, like I have other track cars, so the pad selection can account for that. Then again, I seem to always end up threshold braking!

Thanks in advance,

Bruce

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Hi Bruce,

I have some experience now with the Corsas and the brakes. I have driven a few thousand miles on the street P Zeros and they look like new. I have not tracked the street P Zeros, just the Corsas. I think that the Corsa would do fine in the rain, it is definitely a rain tire design as compared to MPSCs or any other R compound. My friend Gary tracked his street P Zeros at Willow Springs, a very high speed track known to punish tires. He was very complimentary about the street P Zeros. I will ask him to respond to your post. In case you're curious about the Corsas... The Corsas wore the 2nd row from the outside unusually fast on my first track day ("the groove of doom"), which was in up to 106 degree F weather. The 2nd and 3rd times I tracked it, the wear evened out and appears about normal for an R compound. Still plenty of life left in the Corsas. The Corsas performed MUCH better than the MPSCs in colder weather, and the Corsas would clearly be superior to the MPSCs in the wet, although I haven't driven either in the wet. I suspect the MPSCs would grip better in temperatures above 70 F.

On to the brakes. My front factory pads were down to 2mm after 3 track days and 4,500 miles of street/track. My rears still had 9 or 10mm, very little wear. The stock pads performed very well, never any fade or other issues, other than they wear out faster than I'd like.

On advice of Jon B of Parts Rack, I now run Brakeman 3 pads (the "new" compound) on the front. These are rotor-friendly, track/street pads. Not as aggressive as a full track pad, but much more streetable. Initial bite is strong and linear even when cold, more bite than the factory pads. They feel much like the factory pads on the street. They performed very well over the two track days, and have worn less than the factory pads did in 2 track days. I think I'll get 6 track days out of them on the front, instead of 3 to 4 from the factory pads. When the rear factory pads wear out, I'll swap them for Brakeman 3s as well. I'm starting to hear a little intermittent noise from the Brakemans on the street, but nowhere near what you would hear from a typical track pad. I will give them a few hard stops to re burnish them if they become noisy. Last time I drove them, no noise at all so it is rare so far. So my take is that Motoman 3s are an excellent pad that will last longer than the stock pads. One nice feature of the Viper - the front and rear pads are the same, so you can swap them front to rear if need be. The fronts wear out much faster than the rears, so this is a good thing. Of course, you'll want to turn or at least clean the rotors before switching from factory to Brakemans, as the compounds are different and won't play together.

I haven't swapped the pads myself yet, but will likely learn how soon. I purchased the service manual CD from Mark Jorgensen. One other item, and I'd like to get your opinion on this- I was planning on flushing my Dot 4 Motul 600 fluid at least every 6 months, but a number of Viper guys (Mark included) recommend a flush every 2 track days, 4 at the most. That's more frequent than I was planning, how often do you think you'll flush?

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Bruce,

A little more to add, perhaps you can comment. I picked up my Viper after service tonight (oil, trans, diff, air filter, inspection). After 5 track days, 2 of which were on the Brakeman 3 pads in the front, my front rotors are showing lots of small cracks (the typical spider web of small rotor cracks as a rotor ages, no separation or anything big yet). I've seen this on my friend's track cars, I don't know if this is premature or normal. According to my dealer, who races occasionally for fun, the cracks should be watched but are not yet a concern. He suggested I ask my brake guy who's an experienced racer and is a safety marshal for the Shelby Club track events. Does this seem early after only 5 track days, or about right?

Todd

 

[sjfirebird]

Hey Bruce

I did track my car back in October at Willow Springs. My GTS is 100% stock with the P-Zeros. I had the wheel alignment and camber measured before my track day and they were right on factory specifications. I did about 42 laps at at Willows Springs averaging anywhere between 92 to 97 mph per lap topping out at 143 mph on the main straight. I also spent about 20 minutes on the skidpad screwing around trying to test the limits of the car. By the way, that was hell of fun!

The tires held up very well. Looking at the treads, they certainly look like they've been on the track but there are no chunks or abnormal wear patterns. It's hard for me to estimate how much wear I did put on, but I think it was very reasonable for the speed and condition of the track (it was probably 70 degrees). I would also add that the tires gave me plenty of grip and not once did I lose adhesion other than when I was braking and down shifting too hard. On two occasions, I felt the backend get a little loose but that was not due to the tires. If you are interested, I did take some photos of my front tires during and after the event. I'd be happy to email them (can't post them from my phone)

I have not had my brakes checked but as Todd said, I also had no fade on the track. They were rock solid.

 

[sjfirebird]

Figured it out

 

[sjfirebird]

Here are my front tires

 

[Nine Ball]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

I drove my car across the country 3 times on the Corsa track pack tires. They are an excellent road tire, and work very well in rain. I drove a few hours in hard rain, they work surprisingly well. I've even had it on the road course in the rain on those tires. Much better than the PS2 or Sport Cup Michelins, when wet. They also seem to wear out slower than what I'd thought they would. No real chunking at the track.

 

[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Thanks for all the feedback fellas,

Todd,

I don't know the wear characteristics of the Corsa so I checked Tirerack and found that the Corsa "require" shaving for track use. See the bottom of http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=67. It's the only R-compound listed that does, where others are optional or recommended. Perhaps the wear you noted, and perhaps SRT providing a test car with worn (shaved?) tires, is the reason why.

I think Mark's brake flush based on number of track days is a good idea, and I think every 2 days for an aggressive driver in a Viper is probably what I would do. As far as heat checking goes, that's pretty common in my experience with track day cars. Letting the pads wear down to 2 mm is asking for trouble though as the limited pad material is less able to absorb heat, which then has to be absorbed by the calipers/fluid and rotor. One time I let a pad wear down accidentally to nothing the rotor completely cracked all the way through that face. Yours wasn't as bad but I'd keep a close eye on it. The particular pad material also impacts the way heat is transferred as well. I would suggest that pad wear could be a contributing factor to your front rotor checking. I just examined the rotors on the XKR with 5 track days, and while the fronts have slight warping from aggressive track use, there's no checking yet and maybe 6 mm of pad. Different Brembo brake system and car. The Supra and MR2's rotors have always checked.

Bruce

 

[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

sjfirebird and Tony,

Thanks for the feedback. It sounds like both tires are meeting expectations. Like to learn more about the Corsas.

Bruce

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Thanks for all the feedback fellas,

Todd,

I don't know the wear characteristics of the Corsa so I checked Tirerack and found that the Corsa "require" shaving for track use. See the bottom of http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=67. It's the only R-compound listed that does, where others are optional or recommended. Perhaps the wear you noted, and perhaps SRT providing a test car with worn (shaved?) tires, is the reason why.

I think Mark's brake flush based on number of track days is a good idea, and I think every 2 days for an aggressive driver in a Viper is probably what I would do. As far as heat checking goes, that's pretty common in my experience with track day cars. Letting the pads wear down to 2 mm is asking for trouble though as the limited pad material is less able to absorb heat, which then has to be absorbed by the calipers/fluid and rotor. One time I let a pad wear down accidentally to nothing the rotor completely cracked all the way through that face. Yours wasn't as bad but I'd keep a close eye on it. The particular pad material also impacts the way heat is transferred as well. I would suggest that pad wear could be a contributing factor to your front rotor checking. I just examined the rotors on the XKR with 5 track days, and while the fronts have slight warping from aggressive track use, there's no checking yet and maybe 6 mm of pad. Different Brembo brake system and car. The Supra and MR2's rotors have always checked.

Bruce

Great detective work, Bruce. That was our other theory, that maybe shaving would've prevented the groove of doom. Now we know. This is disappointing, as this brings the delivered price including shaving to about $3,000 US, and who knows how many track days they would last given that they'd be starting with less tread.

I'm going to throw a curve ball now. RedSled turned me onto discontinued slicks made and sold by Hoosier. These slicks are brand new. This is what he runs. In fact, the other 5 Vipers that I ran with last event were either on slicks or Hoosiers. Get this- they are as little as $115 each, plus only $15 shipping for the whole order. So that's $475 delivered, at least for us in the US. Not sure what cost and availability would be in Canada. This price delta is so good and of course the car would stick like glue that I am going to try it. A friend of mine has a lightweight aluminum trailer that he offered to loan me so that I could pull the Viper to my next tracking event. The sizes aren't perfect, but for that price, it's worth a shot.

They are Continental Radial Slicks (made by Hoosier):
Front: 305/660-18 GT-R $115
Rear: 325/710-19 GT-R $230, or GT-O $115 (I'll call them to investigate what these compounds are like, and if I should mix GT-Rs front and GT-Os rear, to save money)

https://www.hoosiertire.com/discontinuedtires.htm

For the Camaro, there are a bunch of choices of various compounds, all for $115 each. So for the Camaro, I'm thinking of pulling a mini-trailer behind it with the slicks, jack and a tool box. Several companies make small receiver hitches that tuck nicely under the back of the Camaro.

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Hey Bruce

I did track my car back in October at Willow Springs. My GTS is 100% stock with the P-Zeros. I had the wheel alignment and camber measured before my track day and they were right on factory specifications. I did about 42 laps at at Willows Springs averaging anywhere between 92 to 97 mph per lap topping out at 143 mph on the main straight. I also spent about 20 minutes on the skidpad screwing around trying to test the limits of the car. By the way, that was hell of fun!

The tires held up very well. Looking at the treads, they certainly look like they've been on the track but there are no chunks or abnormal wear patterns. It's hard for me to estimate how much wear I did put on, but I think it was very reasonable for the speed and condition of the track (it was probably 70 degrees). I would also add that the tires gave me plenty of grip and not once did I lose adhesion other than when I was braking and down shifting too hard. On two occasions, I felt the backend get a little loose but that was not due to the tires. If you are interested, I did take some photos of my front tires during and after the event. I'd be happy to email them (can't post them from my phone)

I have not had my brakes checked but as Todd said, I also had no fade on the track. They were rock solid.

Gary, thanks for posting up. Did you run Willow Springs with West Coast Racing (Jim Sexton organized this event)? He has another one on March 1 - 2, and I will likely be there my Viper. I heard about 10 Vipers were there last event. Join me if you can. I'll send you the info if interested.

 

[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

If you're trying to maximize performance then you've really always had to shave most R-compounds to remove enough tread and squirm so that it runs cool enough to not be destroyed on the track. Heat cycling is also critical on some tires. I would only get 1-2 track days out of the 285/30/18 Kumho Esta 700's on the front of the Supra. The tire would actually delaminate, with large strips peeling off the tire, and my fastest laps were just before it came apart...or perhaps because of it! I bought several on clear-out for $50 each and had a blast.

I'm going to consider using the Corsas as both you and Tony have successfully done, go a bit easy on track with this set to avoid over-heating them, and then if I like them in all other respects maybe order them shaved next time unless a more appealing option presents itself. $3000 is a lot of coin, but I have a feeling I will get very good wear from a shaved set with the extra neg. camber, limited heat cycles, and only a 45 minutes drive to get to my home track.

I'd like to pickup a set of used Gen V wheels with the stock P-Zero tires on them if anyone happens to have a set they'd like to sell, and then I can use them more for normal use. (If anyone has a set for sale please PM me).

We're likely to learn a lot about the Corsas once more guys get them on the track. I like the price of those slick...hopefully you'll have good feedback to share...good luck!

Bruce

 

[Nine Ball]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

The price of the rear 355 Corsa is going to make them not worth replacing. Roughly $900... each.

No tire is worth $900 to me. Especially when Michelin Pilot Sport Cups cost less. I run the Michelin Pilot Super Sports for my road wheels, excellent tire.

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

The price of the rear 355 Corsa is going to make them not worth replacing. Roughly $900... each.

No tire is worth $900 to me. Especially when Michelin Pilot Sport Cups cost less. I run the Michelin Pilot Super Sports for my road wheels, excellent tire.

Totally agree. We don't have a lot of choices. The Sport Cups don't grip in the cold, only good for the summer. Corsas are better in the cold, but are pricey and you have to shave 'em. Super Sports don't fit the stock wheels well. Neither do PS2s. No great choices out there.

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

If you're trying to maximize performance then you've really always had to shave most R-compounds to remove enough tread and squirm so that it runs cool enough to not be destroyed on the track. Heat cycling is also critical on some tires. I would only get 1-2 track days out of the 285/30/18 Kumho Esta 700's on the front of the Supra. The tire would actually delaminate, with large strips peeling off the tire, and my fastest laps were just before it came apart...or perhaps because of it! I bought several on clear-out for $50 each and had a blast.

I'm going to consider using the Corsas as both you and Tony have successfully done, go a bit easy on track with this set to avoid over-heating them, and then if I like them in all other respects maybe order them shaved next time unless a more appealing option presents itself. $3000 is a lot of coin, but I have a feeling I will get very good wear from a shaved set with the extra neg. camber, limited heat cycles, and only a 45 minutes drive to get to my home track.

I'd like to pickup a set of used Gen V wheels with the stock P-Zero tires on them if anyone happens to have a set they'd like to sell, and then I can use them more for normal use. (If anyone has a set for sale please PM me).

We're likely to learn a lot about the Corsas once more guys get them on the track. I like the price of those slick...hopefully you'll have good feedback to share...good luck!

Bruce

Bruce,

Check with Jon B of Parts Rack. The Sidewinder IIs are surprisingly inexpensive, and they are the lightest wheels out there.

 

[Nine Ball]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Totally agree. We don't have a lot of choices. The Sport Cups don't grip in the cold, only good for the summer. Corsas are better in the cold, but are pricey and you have to shave 'em. Super Sports don't fit the stock wheels well. Neither do PS2s. No great choices out there.

Michelin Pilot Super Sports fit the stock wheels excellent. Every Gen 3-5 Viper has identical 13.0 wide rear wheels, btw.

285/35-18 front (factory rated for up to an 11.0 front wheel, ours are 10.5)
345/30-19 rear

Both of these are 10mm narrower than the stock Gen 5 tires, so the contact patch ratio front to rear is identical. The slightly taller front tire will also look better on the car, filling that huge wheel gap up.

Tony

 

[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Michelin Pilot Super Sports fit the stock wheels excellent. Every Gen 3-5 Viper has identical 13.0 wide rear wheels, btw.

285/35-18 front (factory rated for up to an 11.0 front wheel, ours are 10.5)
345/30-19 rear

Both of these are 10mm narrower than the stock Gen 5 tires, so the contact patch ratio front to rear is identical. The slightly taller front tire will also look better on the car, filling that huge wheel gap up.

Tony

Tony,

I see though that the MPSS 345 is listed requiring an 11.5-12.5" rim, not 13". You're obviously using them and feel they fit the rim fine, but I wonder why Michelin would spec max 12.5" and not 13", particularly knowing that's a Viper size?

Also, have you seen anything from SRT to say that a .9" taller front tire won't throw off the ESC at all?

I have thought it odd that the Viper uses an 18" front and 19" rear. A 19/20 would seem to give more room for the front brakes, have a greater availability of sizes, and still give the advantage of short front sidewall for turn-in and taller rear sidewall for rear grip.

Bruce

 

[Nine Ball]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

345/35-19 is a factory Viper tire size, for Gen 3-4. They fit well on the 13.0, but I agree that 12.5 is ideal appearance-wise. I typically spec my Viper and Z06 customer rear wheels to 12.5 because it looks better.

I'm running the taller front tires on my Gen 5 now, and have 3 customers doing the same. No issues at all. The Gen 5 has a puny 25" tall front tire from the factory, which is shorter than the Gen 3-4 tires. Running the taller Gen 3-4 tires seems to work (and look) perfectly.

Honestly, I'd prefer to have seen the Viper with 19/19. Not a fan of 20" rears. I run the 19/19 on both of my Vipers. I like the appearance of the thicker rear sidewall vs the front.

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[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Thanks Tony...it sounds like the MPSS is a very good alternative to the Pirellis. I'm concerned about using an R-compound tire like the Corsa extensively on the street due to the excessive number of heat cycles that would very much deteriorate their performance when then used on a road course. That just defeats the purpose of running an R-compound. The tire's grip could be gone long before the tread is...unless the Corsa behaves differently than most other R's.

Bruce

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

I agree about the heat cycling issue, that's why I did what you're planning and have a set just for the track. I have to say that after running the MPSCs, I gained respect for the Corsas. I ran the Corsas in 107 degree F weather at Thunderhill and in sessions as cold as high 40's at Laguna Seca, and they stuck very well. In between those track days, I drove 9 hours to Spring Mountain, tracked, then 9 hours home, and tires were still very grippy. Wear was surprisingly good too, once I got past the initial groove of doom issue. A shaved Corsa is a very good track tire, except for its cost. So far I like Corsas better than the MPSCs but will reserve judgement until I run them in the summer.

Regarding Super Sports, I just can't get past the idea of raising the nose 0.45". I'd rather go down than up. Can't be good for handling either.

345s came on the Gen IV with 13" wide wheels so that's not a problem. I just hope the 325 slicks will work ok.

 

[TrackAire]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

At a bare minimum, for those that track hard and often a dedicated set of track rims/tires is a must. I've seen a couple of cars get damaged tires at track events and with no spare, what do you do on a Sunday afternoon when you need a giant Viper tire? The problem is getting your race tires to the track. Assuming that the driver only wants to drive his car to track, either a small trailer behind the Viper or having a friend haul them to track is a logical answer.

Here is another thought. Maybe we can find a contact (existing shop or business at each individual track) and make a deal to ship the tires to them before the event, drop them off after the event and they'll ship them back. Obviously this will cost money for the shipping and a fee for the shop to slap labels back on the set of tires. By using the people volume of the Viper clubs, Camaro clubs, Vette clubs, etc, there might be enough business there for a track shop owner to actually consider this as beneficial to both sides.

It would be pretty easy to use boxes sized to fit your rims/tires to protect the rim from scratches during shipping. Shipping could be set up by a company like UPS or California Overnight, etc. It could probably be set up that labels can be printed off your computer for the ship to and back to your home and then just tape them to the box for the shipping back home from the track.

Cheers,
George

 

[Nine Ball]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Even with the taller MPSS front tire, my car still has a forward rake. Still on stock suspension. Look how nice that front fender gap is, compared how it looked stock. This taller front tire is the correct size on the Gen 3/4 cars, not sure why they went with the puny front tire on the Gen V. Might be all that Pirelli had at the time. You can tell they likely set the front spring height based on the previous gen front tire height though.

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[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Tony,

The rake and gap does look great, but that picture of yours is with the 19" front wheel/tire, not the 18" with 285/35/18 MPSS tires we're talking about, right?

 

[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Todd,

Did you do a formal R-Compound tire break-in with the Corsas, or just some street use before putting them on the track? And what hot pressures are you running them on track?

Bruce

 

[VENOM V]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Todd,

Did you do a formal R-Compound tire break-in with the Corsas, or just some street use before putting them on the track? And what hot pressures are you running them on track?

Bruce

I thought hard about how I would accomplish it, but there was no safe place around here to drive the car hard enough. So I just skipped it. The brand new Corsas were driven 200 miles to the track one evening and then tracked the next day. However, I did order Tire Rack's heat cycling option for the MPSCs that are on my track wheels now. A friend of mine did a careful test on his Mustang track car. He was skeptical about whether heat cycling is beneficial. After recording the number of heat cycles on a set with, and another without heat cycling, he confirmed that the heat cycled tires lasted longer (more cycles) before grip went away. So he made me a true believer that it works. That said, my Corsas have been through 20 heat cycles on track plus about 2,000 street miles and grip is still great. I was turning some pretty fast laps at Laguna Seca last I used them. Still about 1/2 tread depth remains as well.

 

[Nine Ball]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Tony,

The rake and gap does look great, but that picture of yours is with the 19" front wheel/tire, not the 18" with 285/35/18 MPSS tires we're talking about, right?

My Forgelines are 19x10.5 front with 295/30-19 MPSS tires. They are 26.0" tall, 1 inch taller than the stock tire.

 

[Bruce H.]

Re: Driving TA on street P-Zeros for road trips to distant tracks, and spare brake pa

Todd,

Well, I guess it's possible that the lack of a proper break-in contributed to your "groove of doom", which I assume to be excessive wear of that 2nd row. I'll probably just **** it up and use the Corsas when I get it for learning the car, an HPDE or 2, and then the big trip to RA and VIR. They'll be toast by the time I get back based on your experience, although I won't be pushing as hard when I'm that far from home. My biggest concern now is keeping the tires from freezing after it leaves the factory probably next month. The transport won't be heated, and even just rolling a car on frozen R-Compounds is really bad. I spoke to the dealer this month and he thinks he can keep the car inside waiting for temps to warm up in March until delivery to me.

Tony,

Okay, same thing, that makes sense. Ride height looks perfect.

Bruce