R comps vs. Street tires
02-17-2010, 11:30 PM
#16
I been driving DE events for about 10 years. The past 5 years I have been using Hoosiers and most recently BFG R1's. Last fall we had an event that was rainy and then would dry up and then rain again. Rather then changing wheels over and over I just kept my street tires on. They are Hankook V12 Evo's (a high performance summer Tire). I was amazed at how much grip and how little tread squirm they had. I did find braking different. Having run Toyo RA-1's in the past I found these very comparable in performance to the Toyo's. Probably only 2 or 3 seconds slower then the BFG's. I am also impressed by the Michelin PS-2's that have been on many of my students cars. There are many high performance summer tires made and they will like your street allignment.
02-18-2010, 12:30 AM
#17
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Another plug for RA1s. No longer produced in my sizes (245/305 x 18), so I stocked up (1 half gone on the wheels, 2 sets in waiting). Not sure what's left in the warehouse. It's perhaps the all-around best balanced tire going. Fine in the cold and wet, great in the dry. A "real" Sport Cup (meaning not the Porsche N 19s) can be ever so slightly quicker in the dry, but you pay for it in the wet and cold.
02-18-2010, 08:31 AM
#18
Rennlist Member
I used to drive the MPSC on the street - no problems.
I think the RA1s and Nittos are also great recommendations.
(And I've been known to drive to Lime Rock on my BFG R1s or Hoosiers, but that's only about 40 miles for me...)
02-18-2010, 01:43 PM
#20
Hi guys, one more classic 'dual use, good at neither' thread:
I now do about 12 track days a year, and am a signed-off (but still novice, improving) driver. I have about 30 days of PCA DE experience, spread over the last 5 years. My interest is in learning, not outright speed/performance.
I wil have a second set of wheels available and am debating whether to get R comps or good performacne street tires (RE11, Direzza Star Spec). My alignment is set conservatively (1.75 degrees neg camber) on stock ROW Euro suspension since I still do about 5K miles a year of street driving. I have been trying to maintain a reasonable wear pattern.
Are R comps even an option with such an alignment?
Alignment values aside, any ideas about the cost effectiveness of either approach (wear rate/cost of tires?)
What would you do if you were in my shoes?
Thanks for any tips and advice.
Best,
Matt
I now do about 12 track days a year, and am a signed-off (but still novice, improving) driver. I have about 30 days of PCA DE experience, spread over the last 5 years. My interest is in learning, not outright speed/performance.
I wil have a second set of wheels available and am debating whether to get R comps or good performacne street tires (RE11, Direzza Star Spec). My alignment is set conservatively (1.75 degrees neg camber) on stock ROW Euro suspension since I still do about 5K miles a year of street driving. I have been trying to maintain a reasonable wear pattern.
Are R comps even an option with such an alignment?
Alignment values aside, any ideas about the cost effectiveness of either approach (wear rate/cost of tires?)
What would you do if you were in my shoes?
Thanks for any tips and advice.
Best,
Matt
First: You will get a much better return by installing your Euro seats and getting harnesses. There is no substitute for being able to feel what the car is doing. On a track under 2 miles a proper setup (seats etc) is probably worth 2-3 seconds right off the bat, and another second or two over the long haul.
Second:As for tires, they are the only thing keeping the car on the road, so you will benefit from having the right tool for the job.
Lots of people say that street tires are a great learning tool - and they are. But there are some things you don't/can't learn on street tires. Although you will learn car control skills that translate to R-comps, there is no substitute for feeling 1.5+Gs [or whatever your platform generates] under braking and in the corners, or feeling the car progressively slide at the limit. On street tires, things happen relatively slowly, so you have time to react. On R-comps, things happen quickly, so you have to be way in front of the car. There are a number of other differences, but IMO, you are doing yourself a disservice by not going to R-comps (assuming you do have a good core set of skills).
I am certain that with racing seats, harnesses, and R-comps, your progression will be much faster than with street tires and 3-point seat belts.
Third: your alignment will affect tire wear, but going from -1.75 to -2.5 degrees negative camber will not be that dramatic. A proper alignment does help, but you are not really that far off. Some tires like a little more negative camber, some a little less. But you are generally in the range to get decent performance. Keep in mind that more negative camber is good on the track, but eats the inside on the street. [I buy "hard" street tires and leave the car setup for the track].
-td
02-18-2010, 03:29 PM
#21
Rennlist Member
I couldn't possibly disagree more with that statement. Going back to street tires is an absolute blast. You can really push the car to its limits and you get lots of feedback to help keep from going PAST the limits and getting into trouble. Yes they're slower, but they're a lot funner.
02-18-2010, 04:42 PM
#22
Rennlist Member
Brian_77_3.6 wrote:
Sorry OT, unless OP decides to go R compound.
How do the BFG R1's compare to Hoosiers in terms of durability?
I like how long the RA1's last and they are good to the end, but they are pricier than both the Hoosiers and BFG R1's.
18"
locally quoted.
RA1 245/40/18 $289
RA1 335/30/18 $426
Tire Rack
Hoosier 255/40/18 or 265/35/18 $297 or $300
Hoosier 345/35/18 $376
Tire Rack
BFG 245/40/18 $277 265/35/18 $254
BFG 335/30/18 $318
I been driving DE events for about 10 years. The past 5 years I have been using Hoosiers and most recently BFG R1's.
How do the BFG R1's compare to Hoosiers in terms of durability?
I like how long the RA1's last and they are good to the end, but they are pricier than both the Hoosiers and BFG R1's.
18"
locally quoted.
RA1 245/40/18 $289
RA1 335/30/18 $426
Tire Rack
Hoosier 255/40/18 or 265/35/18 $297 or $300
Hoosier 345/35/18 $376
Tire Rack
BFG 245/40/18 $277 265/35/18 $254
BFG 335/30/18 $318
02-18-2010, 05:40 PM
#23
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There's not as much difference between good street tires like PS2s and R-compound tires. A couple of seconds over a long track isn't earth-shattering. Telemetry (G loads, lap times, etc.) showed that there's not much difference between PS2 and the faux PSCup (19" Porsche N rated). Almost exactly the same in lateral and braking Gs. RA1s are better, haven't used Hoosiers, but I know they are gripper (but you give up wet and cold performance, durability).
02-18-2010, 06:06 PM
#24
Rennlist Member
I need 315/17's, have to go with NT-01's on my hot rod.
02-18-2010, 06:31 PM
#25
May I throw a recommendation in here for the Bridgestone RE-11.
Best street tire I've ever driven on track. No, it's not an R-comp, but it's darn close. Stiff sidewalls, very grippy, minimal tread squirm, doesn't overheat unless you _really_ abuse it.
And, the "Uni-T" rubber compound construction means that the tire starts with "softer" rubber under the surface. As the tire wears and heat-cycles, that softer rubber hardens up a little bit to where it is equivalent to the grip that you started with when the tire was new.
In other words, a grippy almost-R-comp that keeps its grip no matter how much it is heat-cycled.
It truly is amazing the level of tire technology that exists today.
Best street tire I've ever driven on track. No, it's not an R-comp, but it's darn close. Stiff sidewalls, very grippy, minimal tread squirm, doesn't overheat unless you _really_ abuse it.
And, the "Uni-T" rubber compound construction means that the tire starts with "softer" rubber under the surface. As the tire wears and heat-cycles, that softer rubber hardens up a little bit to where it is equivalent to the grip that you started with when the tire was new.
In other words, a grippy almost-R-comp that keeps its grip no matter how much it is heat-cycled.
It truly is amazing the level of tire technology that exists today.
02-18-2010, 07:46 PM
#26
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I researched what sizes RA1 were slated for return to production and got this:
The only thing we know for sure now is that the RA1's that were brought back are the ones they use for spec tires in NASA & SCCA. As fas the R888 goes Toyo has said they are going to keep it around.
We received the info back for Toyo the only 18" RA1 that will be brought back into production is the 275/35-18. No other tires at this time other than the limited RA1's and the complete line of R888's will be offered in the US.
The only thing we know for sure now is that the RA1's that were brought back are the ones they use for spec tires in NASA & SCCA. As fas the R888 goes Toyo has said they are going to keep it around.
We received the info back for Toyo the only 18" RA1 that will be brought back into production is the 275/35-18. No other tires at this time other than the limited RA1's and the complete line of R888's will be offered in the US.
02-19-2010, 02:55 PM
#27
Rennlist Member
Thread Starter
My vote is for you to get either Nitto NT01s or Toyo RA1s (both R-comps) for the following reasons. These tires will give you a lot more grip than street tires, and they're no more expensive then good street tires. You also do not need to worry about them "aging out" before you get full use out of them because they age well. At 12 events/year, you're doing 50 heat cycles anyway. You'd be better with more neg camber, but 1.75 is pretty close.
Personally, I moved to R-compounds a few years ago, and then last year went "purist" running a season of DE with street tires. In the end, the street tires got flat spotted and I was simply going slower and making more noise! Moral victories come few and far between when you DE in a 944 n/a, so I'm back to R-compounds this year.
Personally, I moved to R-compounds a few years ago, and then last year went "purist" running a season of DE with street tires. In the end, the street tires got flat spotted and I was simply going slower and making more noise! Moral victories come few and far between when you DE in a 944 n/a, so I'm back to R-compounds this year.
I run Nitto NT-05 for street and really think they would be a great tire for you. I ran them in the constant rain at Calabogie event last september and they were great. If I were you, I wouldn't run MPSC simply because they suck in the rain, they heat cycle out before you even cord them. Really, for mild use, I would consider NT-05 or NT-01 for R-comp.
Another plug for RA1s. No longer produced in my sizes (245/305 x 18), so I stocked up (1 half gone on the wheels, 2 sets in waiting). Not sure what's left in the warehouse. It's perhaps the all-around best balanced tire going. Fine in the cold and wet, great in the dry. A "real" Sport Cup (meaning not the Porsche N 19s) can be ever so slightly quicker in the dry, but you pay for it in the wet and cold.
My thoughts:
First: You will get a much better return by installing your Euro seats and getting harnesses. There is no substitute for being able to feel what the car is doing. On a track under 2 miles a proper setup (seats etc) is probably worth 2-3 seconds right off the bat, and another second or two over the long haul.
Second:As for tires, they are the only thing keeping the car on the road, so you will benefit from having the right tool for the job.
Lots of people say that street tires are a great learning tool - and they are. But there are some things you don't/can't learn on street tires. Although you will learn car control skills that translate to R-comps, there is no substitute for feeling 1.5+Gs [or whatever your platform generates] under braking and in the corners, or feeling the car progressively slide at the limit. On street tires, things happen relatively slowly, so you have time to react. On R-comps, things happen quickly, so you have to be way in front of the car. There are a number of other differences, but IMO, you are doing yourself a disservice by not going to R-comps (assuming you do have a good core set of skills).
I am certain that with racing seats, harnesses, and R-comps, your progression will be much faster than with street tires and 3-point seat belts.
Third: your alignment will affect tire wear, but going from -1.75 to -2.5 degrees negative camber will not be that dramatic. A proper alignment does help, but you are not really that far off. Some tires like a little more negative camber, some a little less. But you are generally in the range to get decent performance. Keep in mind that more negative camber is good on the track, but eats the inside on the street.
First: You will get a much better return by installing your Euro seats and getting harnesses. There is no substitute for being able to feel what the car is doing. On a track under 2 miles a proper setup (seats etc) is probably worth 2-3 seconds right off the bat, and another second or two over the long haul.
Second:As for tires, they are the only thing keeping the car on the road, so you will benefit from having the right tool for the job.
Lots of people say that street tires are a great learning tool - and they are. But there are some things you don't/can't learn on street tires. Although you will learn car control skills that translate to R-comps, there is no substitute for feeling 1.5+Gs [or whatever your platform generates] under braking and in the corners, or feeling the car progressively slide at the limit. On street tires, things happen relatively slowly, so you have time to react. On R-comps, things happen quickly, so you have to be way in front of the car. There are a number of other differences, but IMO, you are doing yourself a disservice by not going to R-comps (assuming you do have a good core set of skills).
I am certain that with racing seats, harnesses, and R-comps, your progression will be much faster than with street tires and 3-point seat belts.
Third: your alignment will affect tire wear, but going from -1.75 to -2.5 degrees negative camber will not be that dramatic. A proper alignment does help, but you are not really that far off. Some tires like a little more negative camber, some a little less. But you are generally in the range to get decent performance. Keep in mind that more negative camber is good on the track, but eats the inside on the street.
Heard a rumor they were back in full production and on their site they list all sizes - http://toyotires.com/tire/pattern/proxes-ra1
I need 315/17's, have to go with NT-01's on my hot rod.
I need 315/17's, have to go with NT-01's on my hot rod.
I researched what sizes RA1 were slated for return to production and got this:
The only thing we know for sure now is that the RA1's that were brought back are the ones they use for spec tires in NASA & SCCA. As fas the R888 goes Toyo has said they are going to keep it around.
We received the info back for Toyo the only 18" RA1 that will be brought back into production is the 275/35-18. No other tires at this time other than the limited RA1's and the complete line of R888's will be offered in the US.
The only thing we know for sure now is that the RA1's that were brought back are the ones they use for spec tires in NASA & SCCA. As fas the R888 goes Toyo has said they are going to keep it around.
We received the info back for Toyo the only 18" RA1 that will be brought back into production is the 275/35-18. No other tires at this time other than the limited RA1's and the complete line of R888's will be offered in the US.
Best,
Matt
02-19-2010, 03:01 PM
#28
Rennlist Member
Thread Starter
Quick follow-on question:
The appeal of the RA-1's was their wet performance. I understand that PSC's are specifically bad in the wet.
How do the NT-01's fare in that department?
Best,
Matt
The appeal of the RA-1's was their wet performance. I understand that PSC's are specifically bad in the wet.
How do the NT-01's fare in that department?
Best,
Matt
02-19-2010, 03:46 PM
#30
The MPSC is not a great tire IMO for short sessions. They take too long to get operating temperature.
-td