225/45/15 BFG g-Force Rival
06-02-2013, 09:22 PM
#124
Took them out to Texas A@M for a autoX practice event. 3 of my friends (a MSM and 2 drivers in a mini) and I were all running different size rivals.
It had rained that morning and they were loose as hell as we were all hydro planing through huge puddles there were right in the middle of a few turns and slaloms. Every one else was spinning out two including a subaru.
As they day went on and the course dried they really began to grip. It seemed the hotter I got them the more they gripped. They did not seem to get slick even when doing 7~8 back to back runs. They got quicker. It was in the low to mid 90s that day.
I'll see how they do when I get around to do a event in the Heat in about 3 weeks.
It had rained that morning and they were loose as hell as we were all hydro planing through huge puddles there were right in the middle of a few turns and slaloms. Every one else was spinning out two including a subaru.
As they day went on and the course dried they really began to grip. It seemed the hotter I got them the more they gripped. They did not seem to get slick even when doing 7~8 back to back runs. They got quicker. It was in the low to mid 90s that day.
I'll see how they do when I get around to do a event in the Heat in about 3 weeks.
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06-04-2013, 10:55 PM
#134
Pick a starting pressure at your next event. 20, 25, 30, 35psi. Doesn't matter. Go out and get them hot. Record tread temps, ambient temp, track surface temp, lap time, hot pressure and brief note about car balance. With that on simple test, you will know more about your particular cars setup than I will ever know from my desk here in California. The key bit will be how much pressure rise you get at the end of one session, thus, your ideal starting pressure.
I make my living helping people make their Miatas faster. Trust me.
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06-04-2013, 11:42 PM
#135
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Thanks for the insight. Having never raced anything ever, I have no clue.
I assumed your testing of this size and brand tire on track preped miatas in varying conditions resulted in a relatively narrow pressure range. A starting range you could suggest before continuing with the fine procedure above.
No offense or ill tone intended.
I assumed your testing of this size and brand tire on track preped miatas in varying conditions resulted in a relatively narrow pressure range. A starting range you could suggest before continuing with the fine procedure above.
No offense or ill tone intended.
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06-05-2013, 12:00 AM
#136
Thanks for the insight. Having never raced anything ever, I have no clue.
I assumed your testing of this size and brand tire on track preped miatas in varying conditions resulted in a relatively narrow pressure range. A starting range you could suggest before continuing with the fine procedure above.
No offense or ill tone intended.
I assumed your testing of this size and brand tire on track preped miatas in varying conditions resulted in a relatively narrow pressure range. A starting range you could suggest before continuing with the fine procedure above.
No offense or ill tone intended.
I'll take an educated guess once I know a little more about your car but you have to promise me you will buy a pyrometer and learn how to use it.
-Is this cold pressure for autocross, time trial, track days, wheel to wheel racing or just for driving around town with the occasional backroad blast?
-Total car weight with driver
-approximate whp
-damper type, brand
-spring rates
-alignment settings
-ride height F/R
-sway bar diameters F/R
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06-16-2013, 09:02 AM
#138
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Just had my first autox event on them, they start working very quickly compared to rs3. This was in 80 degree weather. Definitely felt more grip under braking and acceleration. I didn't have any problem locking them up as I would before on RS3, it seemed easier to modulate the brakes. They seemed a bit more forgiving compared to RS3 when trail braking. There were spots where I know the RS3 would've let go and it would've been oversteering. I had to get used to this. On a slicker lot, I ran 31 psi hot, seemed pretty good at that temp. I don't have a pyrometer so I was just guessing, not sure if that was too high or not. I noticed some people run them as low as 28. With softer suspension I probably want more, right?
This is my setup
445/335 springs (a bit rear biased compared to a usual setup
camber -2.2/1.9
15x9 36
Tubular front sway bar, disconnected rear
torsen
Can't wait to try them at the track, I'm thinking for track I'll probably raise the pressures a bit by 2-3 psi.
Here's a vid of yesterday
This is my setup
445/335 springs (a bit rear biased compared to a usual setup
camber -2.2/1.9
15x9 36
Tubular front sway bar, disconnected rear
torsen
Can't wait to try them at the track, I'm thinking for track I'll probably raise the pressures a bit by 2-3 psi.
Here's a vid of yesterday
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06-16-2013, 03:16 PM
#139
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Setup - '99 NB, Xidas 700/450, RB front sway, N/A, 9" 6ULs, as much camber as possbile.
Previous tire - RS-3's, always higher inside temp than outside, so needed more camber. 30 psi got middle temp 1/2 between inside and outside.
225 Rivals at the track yesterday, 82-95 ambiant
1. Started at 30 psi cold - Insides higher than outsides (needs less camber), middles closer to outsides (needs more air), to 34-35 hot
2. Went to 32 psi cold - Insides still higher than outsides, middles better, but still closer to outsides. to 37 hot
Tires are quicker to turn in, must slow down hands, and noisier. Broke away twice unexpectedly. Times were 4 seconds slower than RS-3s three weeks ago on a 2:15 sec lap, but I may have been trying too hard.
Measuring the exit of corner to the longest straight, 500 RPM less than the RS-3s.
Plan:
1. Start at 34 cold and re-measure.
2. Not sell the RS-3's I took off.
Previous tire - RS-3's, always higher inside temp than outside, so needed more camber. 30 psi got middle temp 1/2 between inside and outside.
225 Rivals at the track yesterday, 82-95 ambiant
1. Started at 30 psi cold - Insides higher than outsides (needs less camber), middles closer to outsides (needs more air), to 34-35 hot
2. Went to 32 psi cold - Insides still higher than outsides, middles better, but still closer to outsides. to 37 hot
Tires are quicker to turn in, must slow down hands, and noisier. Broke away twice unexpectedly. Times were 4 seconds slower than RS-3s three weeks ago on a 2:15 sec lap, but I may have been trying too hard.
Measuring the exit of corner to the longest straight, 500 RPM less than the RS-3s.
Plan:
1. Start at 34 cold and re-measure.
2. Not sell the RS-3's I took off.
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06-16-2013, 03:34 PM
#140
Try to get your hot temps down to 32psig and see how it feels. I'm quite happy in the same range as Slider for autocross, which is nice because he's also my competition, although I was a no show to yesterday's event due to the morning rain and other priorities. I think the lowest I ran was 28psig cold, then maintain them around 30-32 hot with 1psig higher in the front for my setup.
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