MPSC vs. Hoosier- Lateral Gs data
06-09-2006, 01:01 AM
#31
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that settles it... i need to get my car under 2800# so hoosiers won't cord BEFORE they heat cycle out, LOL.
Originally Posted by cstreit
Off track weight with driver and fuel (and NASA GTS margin weight) is 2280# Dry weight is around 1990#. We talked extensively about this on Pelican Parts and basically everyone with cars under 2400# hate 'em, everyone above 2800# love them....
...and yeah, I heat cycle out Hoosiers well before they cord...
...and yeah, I heat cycle out Hoosiers well before they cord...
06-12-2006, 05:04 PM
#32
Nordschleife Master
Here's another data point. I tried Hoosier R6s for the Glen sprint race, and ran a 2:12.0. Put on MPSCs with 22 heat cycles for the enduro and ran a D class best 2:10.2 (3 best time in D ever, and the best for a non 944 turbo cup). Now, I think part of it is that I'm not yet comfortable with the feel of the Hoosiers, but clearly the MPSCs are plenty fast.
06-12-2006, 05:33 PM
#33
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Originally Posted by 38D
Here's another data point. I tried Hoosier R6s for the Glen sprint race, and ran a 2:12.0. Put on MPSCs with 22 heat cycles for the enduro and ran a D class best 2:10.2 (3 best time in D ever, and the best for a non 944 turbo cup). Now, I think part of it is that I'm not yet comfortable with the feel of the Hoosiers, but clearly the MPSCs are plenty fast.
George
06-13-2006, 02:53 PM
#34
Three Wheelin'
MPSC vs Hoosier R6
At the Glen last week I datalogged all my runs and here is what I found...
The MPSC were consistant at 1.0-1.3g with peak of 1.5g in toe and turn 1
The R6s were consistant at 1.2-1.5g with a peak in the toe of 1.75g !!!
The Hoosiers are defintiely faster with more grip, they wear beatutifully even now, have great turn in, but very little feedback. I don't have much experience on full slicks, but the R6s are grip grip slip with little warning they are about to give. This is how slicks have been described to me.
I am happy with them for now. (on my 2nd set)
The MPSC were consistant at 1.0-1.3g with peak of 1.5g in toe and turn 1
The R6s were consistant at 1.2-1.5g with a peak in the toe of 1.75g !!!
The Hoosiers are defintiely faster with more grip, they wear beatutifully even now, have great turn in, but very little feedback. I don't have much experience on full slicks, but the R6s are grip grip slip with little warning they are about to give. This is how slicks have been described to me.
I am happy with them for now. (on my 2nd set)
06-13-2006, 03:06 PM
#35
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that's great Ed.
would you care to share what your suspension settings and tire pressures are? thx
would you care to share what your suspension settings and tire pressures are? thx
Originally Posted by Ed Newman
At the Glen last week I datalogged all my runs and here is what I found...
The MPSC were consistant at 1.0-1.3g with peak of 1.5g in toe and turn 1
The R6s were consistant at 1.2-1.5g with a peak in the toe of 1.75g !!!
The Hoosiers are defintiely faster with more grip, they wear beatutifully even now, have great turn in, but very little feedback. I don't have much experience on full slicks, but the R6s are grip grip slip with little warning they are about to give. This is how slicks have been described to me.
I am happy with them for now. (on my 2nd set)
The MPSC were consistant at 1.0-1.3g with peak of 1.5g in toe and turn 1
The R6s were consistant at 1.2-1.5g with a peak in the toe of 1.75g !!!
The Hoosiers are defintiely faster with more grip, they wear beatutifully even now, have great turn in, but very little feedback. I don't have much experience on full slicks, but the R6s are grip grip slip with little warning they are about to give. This is how slicks have been described to me.
I am happy with them for now. (on my 2nd set)
06-13-2006, 03:32 PM
#36
Three Wheelin'
Moton coilovers @ 150 psi with 700/900 springs, TRG monoballs, GT3 sway bars and -3 deg on all 4 corners. 245/40 Front, 315/30 rear on 9's and 11's. Pressures are 36 hot, car weighs about 2920 plus fuel and driver.
I just made a bunch of mods so the car is not dialed in. It was very loose and I could not figure out why. The car has been clunking and we finally tracked it down to the top nuts on the struts not being tight and the car had 1" of undamped travel on 3 corners. Once we fixed it the car was more stable, but still very loose. Even with that, I managed a few 2:13's in DE and a 2:15 in the race. I think once it i dialed in, the car can run a 2:11 or maybe even a 2:10. Running through the DAS data, if I combine the first half of one lap and the second half from another, it was a 2:11, so the car has it, i need to find out if I have it, lol.
The R6's seem like a winner so far, I need a warm sunny day to get the car really dialed in and get a few more days on them. To be fair, I should be comparing to 265/315 shaved MPSCs, which may be just as fast... but that is another test and more $$$
I just made a bunch of mods so the car is not dialed in. It was very loose and I could not figure out why. The car has been clunking and we finally tracked it down to the top nuts on the struts not being tight and the car had 1" of undamped travel on 3 corners. Once we fixed it the car was more stable, but still very loose. Even with that, I managed a few 2:13's in DE and a 2:15 in the race. I think once it i dialed in, the car can run a 2:11 or maybe even a 2:10. Running through the DAS data, if I combine the first half of one lap and the second half from another, it was a 2:11, so the car has it, i need to find out if I have it, lol.
The R6's seem like a winner so far, I need a warm sunny day to get the car really dialed in and get a few more days on them. To be fair, I should be comparing to 265/315 shaved MPSCs, which may be just as fast... but that is another test and more $$$
06-13-2006, 03:50 PM
#37
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thanx!
i am a little confused, however. most seem to say that hooisers (so4/so5) have a much more progressive breakaway than the MPSC. from what you are saying, the R6's have the same "snap" tendancy as the MPSC. do you think it is your setup or have hoosiers changed?
did you try try them at 40+ pressures (hoosier recommendation)
i am a little confused, however. most seem to say that hooisers (so4/so5) have a much more progressive breakaway than the MPSC. from what you are saying, the R6's have the same "snap" tendancy as the MPSC. do you think it is your setup or have hoosiers changed?
did you try try them at 40+ pressures (hoosier recommendation)
Originally Posted by Ed Newman
Moton coilovers @ 150 psi with 700/900 springs, TRG monoballs, GT3 sway bars and -3 deg on all 4 corners. 245/40 Front, 315/30 rear on 9's and 11's. Pressures are 36 hot, car weighs about 2920 plus fuel and driver.
I just made a bunch of mods so the car is not dialed in. It was very loose and I could not figure out why. The car has been clunking and we finally tracked it down to the top nuts on the struts not being tight and the car had 1" of undamped travel on 3 corners. Once we fixed it the car was more stable, but still very loose. Even with that, I managed a few 2:13's in DE and a 2:15 in the race. I think once it i dialed in, the car can run a 2:11 or maybe even a 2:10. Running through the DAS data, if I combine the first half of one lap and the second half from another, it was a 2:11, so the car has it, i need to find out if I have it, lol.
The R6's seem like a winner so far, I need a warm sunny day to get the car really dialed in and get a few more days on them. To be fair, I should be comparing to 265/315 shaved MPSCs, which may be just as fast... but that is another test and more $$$
I just made a bunch of mods so the car is not dialed in. It was very loose and I could not figure out why. The car has been clunking and we finally tracked it down to the top nuts on the struts not being tight and the car had 1" of undamped travel on 3 corners. Once we fixed it the car was more stable, but still very loose. Even with that, I managed a few 2:13's in DE and a 2:15 in the race. I think once it i dialed in, the car can run a 2:11 or maybe even a 2:10. Running through the DAS data, if I combine the first half of one lap and the second half from another, it was a 2:11, so the car has it, i need to find out if I have it, lol.
The R6's seem like a winner so far, I need a warm sunny day to get the car really dialed in and get a few more days on them. To be fair, I should be comparing to 265/315 shaved MPSCs, which may be just as fast... but that is another test and more $$$
06-13-2006, 04:35 PM
#38
Three Wheelin'
The S04 and S05 were very progressive. The R6s IMO are very different. I found the MPSCs to be pretty progressive without much of a snap. They at least make noise so you can tell when you are pushing them.
06-13-2006, 05:02 PM
#39
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Carlos,
The Hoosier engineers suggest starting with a hot pressure of about 5 lbs less than R4s and adjusting from there. That gets you pretty close to what Ed is running.
I'm on my second set of R6s and am pretty happy. The good news is they seem to last forever. I had about 12 heat cycles on a set and they looked like new. I switched to a set with one cycle thinking I would pick up a second or more like I would have with the R4s. No such luck. The old ones were as fast as the new. These tires might actually last for more than one race weekend.
They also stay sticky for a little bit longer. Maybe 15 minutes rather than 5. Overall all a big improvement.
Jim
The Hoosier engineers suggest starting with a hot pressure of about 5 lbs less than R4s and adjusting from there. That gets you pretty close to what Ed is running.
I'm on my second set of R6s and am pretty happy. The good news is they seem to last forever. I had about 12 heat cycles on a set and they looked like new. I switched to a set with one cycle thinking I would pick up a second or more like I would have with the R4s. No such luck. The old ones were as fast as the new. These tires might actually last for more than one race weekend.
They also stay sticky for a little bit longer. Maybe 15 minutes rather than 5. Overall all a big improvement.
Jim
06-13-2006, 05:50 PM
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Thanks for the good info guys. I will have to give them a try.
Carlos, I run the 05's at 38psi hot. I've been told with the new carcass, you can run the R6's about 2psi lower.
George
Carlos, I run the 05's at 38psi hot. I've been told with the new carcass, you can run the R6's about 2psi lower.
George
06-13-2006, 06:08 PM
#41
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This from Hoosier, as provided for the "Care and feeding of Hoosier R6/A6" information in Tire Rack's Tech section:
Tire Pressure Recommendations for Competition
Traditionally, Hoosier tires have often required higher pressures than other brands. This has changed with the A6/R6.
Roadrace/Track Applications
Vehicle Size Recommended - Hot Pressure - Cold Pressure
1800-2200 lbs 34-37+ 26-31
2200-2600 lbs 35-38+ 27-32
2600-3000 lbs 37-41+ 27-32
over 3000 lbs 38-43+ 27-33
+ Higher pressures will improve the performance capability but will require a more sensitive feel to take advantage of the increase.
One characteristic of the tires is the tendency to "skate" initially (when inflation pressures are correct). It is important to resist lowering the pressure to attempt to eliminate this feeling. Dropping the pressure too far may improve the "feel" of the tire however it will also lower the performance and increase the wear rate.
Tire Pressure Recommendations for Competition
Traditionally, Hoosier tires have often required higher pressures than other brands. This has changed with the A6/R6.
Roadrace/Track Applications
Vehicle Size Recommended - Hot Pressure - Cold Pressure
1800-2200 lbs 34-37+ 26-31
2200-2600 lbs 35-38+ 27-32
2600-3000 lbs 37-41+ 27-32
over 3000 lbs 38-43+ 27-33
+ Higher pressures will improve the performance capability but will require a more sensitive feel to take advantage of the increase.
One characteristic of the tires is the tendency to "skate" initially (when inflation pressures are correct). It is important to resist lowering the pressure to attempt to eliminate this feeling. Dropping the pressure too far may improve the "feel" of the tire however it will also lower the performance and increase the wear rate.
06-13-2006, 10:09 PM
#42
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thx guys,
Ed: that is definetley something to look out for, especially since i am using R5 ft/R6 rr. the hooiser guy and tire rack said that it should cause a little bit of push cuz the R6s are stickier. i'll soon find out.
JimB: great to know that the R6s will last for more than a race weekend. that'll mean it will last 4 events for me. i will be using the MPSCs for saturday practice and the R6s for sunday timetrial. now i wish i got a full set of R6s instead of R5 fronts/R6s rear. hoosier said it would be fine.
George: good data point
Bull: here's a little bit more about the care and feeding of the R6 (from hoosiertire.com)
"Independent rear suspension
With IRS and proper geometry up front, tire pressures can be reduced from the recommendations listed above. When there is adequate camber gain and good roll control, the Hoosier radial tire will perform very well at the reduced air pressure. This results in a bigger "sweet spot" and easier control at the limit.
When tuning at reduced pressures use the following formula to determine the minimum safe pressure: Divide the total vehicle weight, including fuel and driver, by 100 to arrive at the minimum safe pressure. Example: Your car weighs 2750 lbs. as raced. The minimum safe (cold) pressure is 27.5 psi."
Ed: that is definetley something to look out for, especially since i am using R5 ft/R6 rr. the hooiser guy and tire rack said that it should cause a little bit of push cuz the R6s are stickier. i'll soon find out.
JimB: great to know that the R6s will last for more than a race weekend. that'll mean it will last 4 events for me. i will be using the MPSCs for saturday practice and the R6s for sunday timetrial. now i wish i got a full set of R6s instead of R5 fronts/R6s rear. hoosier said it would be fine.
George: good data point
Bull: here's a little bit more about the care and feeding of the R6 (from hoosiertire.com)
"Independent rear suspension
With IRS and proper geometry up front, tire pressures can be reduced from the recommendations listed above. When there is adequate camber gain and good roll control, the Hoosier radial tire will perform very well at the reduced air pressure. This results in a bigger "sweet spot" and easier control at the limit.
When tuning at reduced pressures use the following formula to determine the minimum safe pressure: Divide the total vehicle weight, including fuel and driver, by 100 to arrive at the minimum safe pressure. Example: Your car weighs 2750 lbs. as raced. The minimum safe (cold) pressure is 27.5 psi."
06-14-2006, 01:54 AM
#43
Three Wheelin'
Originally Posted by 38D
Here's another data point. I tried Hoosier R6s for the Glen sprint race, and ran a 2:12.0. Put on MPSCs with 22 heat cycles for the enduro and ran a D class best 2:10.2 (3 best time in D ever, and the best for a non 944 turbo cup). Now, I think part of it is that I'm not yet comfortable with the feel of the Hoosiers, but clearly the MPSCs are plenty fast.
06-14-2006, 10:12 AM
#45
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Originally Posted by Ed Newman
The S04 and S05 were very progressive. The R6s IMO are very different. I found the MPSCs to be pretty progressive without much of a snap. They at least make noise so you can tell when you are pushing them.
When I spoke to the Hoosier rep at their home office, he told me that the 05's and R6's use the same exact compound, the only difference being the carcuss.
Interesting............
George