turn the knob up to 15X11
#1
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I turned it up to 11. 15X11 with Ύ offset Keizer Billets. Weigh ~14.2 LB. 275/35/15 Hoosier A6.
The rear pretty much fits as well as a 15X10 the front is a bit tight. 2.25 springs are needed I think and I offset the shock tops inboard by Ό to cure too much interference between the spring and the rim when turning.
First test pretty much confirmed for me the 275s like 11 wheels. The traction limit behavior is much improved. Same amazing feel I had with the 245s mounted on 10 I crushed overall top time and top PAX at a couple regional autocross events with them now. Pressure can be run about 4 psi lower contact patch stays flatter and its just easier to transition to and drive at the limits of traction.
The rear pretty much fits as well as a 15X10 the front is a bit tight. 2.25 springs are needed I think and I offset the shock tops inboard by Ό to cure too much interference between the spring and the rim when turning.
First test pretty much confirmed for me the 275s like 11 wheels. The traction limit behavior is much improved. Same amazing feel I had with the 245s mounted on 10 I crushed overall top time and top PAX at a couple regional autocross events with them now. Pressure can be run about 4 psi lower contact patch stays flatter and its just easier to transition to and drive at the limits of traction.
#9
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For autocross I have it within 10-20lbs of minimum class weight which is 2080lbs for me. For track I add about 150 lb's of stuff. Which takes 3 about hours.
1) Hard dog Hard Core
2) Harness bar
3) Door bars
4) Custom Front shock tower brace
5) Custom Rear subframe brace
6) Accusump
7) Rear Sway Bar
8) Rear wing swapped
9) Shorter Front Splitter/ undertray
For NASA TT2 time trials I run 245/40/15 to take advantage of the HP/weight advantage for 245 and under DOT tires. I also run lower boost to stay just within the HP/weight rule for TT2 class. I can make about 330 Hp or I have to add more weight. Car actually is more reliable on the track with lower boost which is nice. The car is kind of heavy with me in it in track trim compared to some of the other track beasts around the country but it seems to work well. Kind of odd for a Miata but against my current regional competition in time trials I have more HP/weight and lower grip than the BMW's and Porsches running in class on full on race slicks. I am the muscle car.
#10
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I have a Co-driver. I'm finding once I let people drive my car it works just like crack and I can extract all sorts of stuff like tires, entry fees, and gas.
Your up in this region of the world now. come to Packwood. Saturday June 28th is northwest region SCCA open practice. I don't plan on doing any of the Oregon region events there though just Northwest Region and the VCMC stuff in Canada. Between that a hand full off TTS and Laguna I have a full enough schedule.
Your up in this region of the world now. come to Packwood. Saturday June 28th is northwest region SCCA open practice. I don't plan on doing any of the Oregon region events there though just Northwest Region and the VCMC stuff in Canada. Between that a hand full off TTS and Laguna I have a full enough schedule.
#11
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I should be there. My car has been down since Jan and is about to be running again, so hopefully I'll be able to get back into events...if I can find the extra cash for a set of wheels/tires. Unfortunately Im still on the stock torsen, and as I found out chasing you around at the FM Summer Camp...I can reach its limits too easily :(
#12
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I have it convertible between Autocross and track setup. Its got welded in landing plates for Hard core roll bar and door bars which help make install faster.
For autocross I have it within 10-20lbs of minimum class weight which is 2080lbs for me. For track I add about 150 lb's of stuff. Which takes 3 about hours.
1) Hard dog Hard Core
2) Harness bar
3) Door bars
4) Custom Front shock tower brace
5) Custom Rear subframe brace
6) Accusump
7) Rear Sway Bar
8) Rear wing swapped
9) Shorter Front Splitter/ undertray
For NASA TT2 time trials I run 245/40/15 to take advantage of the HP/weight advantage for 245 and under DOT tires. I also run lower boost to stay just within the HP/weight rule for TT2 class. I can make about 330 Hp or I have to add more weight. Car actually is more reliable on the track with lower boost which is nice. The car is kind of heavy with me in it in track trim compared to some of the other track beasts around the country but it seems to work well. Kind of odd for a Miata but against my current regional competition in time trials I have more HP/weight and lower grip than the BMW's and Porsches running in class on full on race slicks. I am the muscle car.
For autocross I have it within 10-20lbs of minimum class weight which is 2080lbs for me. For track I add about 150 lb's of stuff. Which takes 3 about hours.
1) Hard dog Hard Core
2) Harness bar
3) Door bars
4) Custom Front shock tower brace
5) Custom Rear subframe brace
6) Accusump
7) Rear Sway Bar
8) Rear wing swapped
9) Shorter Front Splitter/ undertray
For NASA TT2 time trials I run 245/40/15 to take advantage of the HP/weight advantage for 245 and under DOT tires. I also run lower boost to stay just within the HP/weight rule for TT2 class. I can make about 330 Hp or I have to add more weight. Car actually is more reliable on the track with lower boost which is nice. The car is kind of heavy with me in it in track trim compared to some of the other track beasts around the country but it seems to work well. Kind of odd for a Miata but against my current regional competition in time trials I have more HP/weight and lower grip than the BMW's and Porsches running in class on full on race slicks. I am the muscle car.
#20
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Pictures with the tires stacked are comparing 10" vs 11" mounting.
Last edited by bbundy; 05-24-2014 at 06:28 PM.