LS1 RX7 corner weighed versus stock RX7 - F-Body Road Racing and Autocross Forums

I weighed both cars over the weekend at our autocross event at giants stadium. Both cars had spare removed. Both had almost full tanks of gas but my car has a reduced capacity tank which holds 5 gallons less (5 gallons at 8 lbs/gallon = 40 lbs). Both had stock 16 x 8 rims but i had 245-45-16's Yok AO32R's and rotary had 265-45-16 Kumho ecsta v700's. My car is missing AC, PS and ABS. My battery is in bin on passenger side whereas stock RX7 has battery in original position up front. Bottom line is mine weighed about 15 lbs more but had a better weight distribution of 50.5/49.5 front to rear and his stock RX7 was 53/47:
--------------LS1 ------- Rotary
Left Front: 684 ------- 718
Right Front: 695 ------- 718
Total Front: 1379 ------- 1436

Left Rear: 705 ------- 660
Right Rear: 645 ------- 618
Total Rear: 1350 ------- 1278
TOTAL: 2729 ------- 2714
% over Front: .505 ------- .530
% over Rear: .495 ------- .470

not a perfect comparison because i have some items remove/relocated, but it just shows it doesn't kill the handling or the weight distribution.

the owner of the stock RX7 was my passenger on the last run; listen to his comments at the very end:
http://207.127.219.37/video/AX.wmv

My fastest time was 54.0 and his was 55.5. His tires (265-45-16 kumbo ecsta v700) were way better than mine (yok AO32R 245-45-16 Hard compound), no comparision. they were wider and stickier. My yok's are hard compound and are better on road courses than autocross. He is SCCA SS class driver that is original owner of the car, which is 93 R1. He races full season and competes in Kopeka, but this was my first autocross of the year!! and my first time ever autocrossing any RX7. He has stock R1 springs (stiffer than my stock non-R1 springs?) and $2000 koni custom valved double adjustable shocks (tripoint) and i have 13 year old stock units. The lack of ABS in my car definitely hurt my times as the video reflects constant right front tire lockup (dusty course, need new bleed because i just installed new master, need to adjust proportioning valve, who knows). He loved the car and how it felt on the course so that means a lot coming from a die hard rotary owner/racer.

After that autocross, i had my car tuned on dyno:

(IMG:http://207.127.219.37/images/rxdyno2.jpg)

with the 2730 lbs curb weight and approx crank hp equalling 460 hp, i have lbs per hp ratio better than new z06 and viper:
me: 2730/460 = 5.93 lbs/hp
viper: 3470/510 hp = 6.80 lbs/HP
C6 z06: 3147/505 hp = 6.23 lbs/HP

2MCHPWR View Member Profile	Nov 12 2005, 05:03 PM Post #1
Member Group: Advanced Members Posts: 218 Joined: 1-March 04 From: NY Member No.: 260	I weighed both cars over the weekend at our autocross event at giants stadium. Both cars had spare removed. Both had almost full tanks of gas but my car has a reduced capacity tank which holds 5 gallons less (5 gallons at 8 lbs/gallon = 40 lbs). Both had stock 16 x 8 rims but i had 245-45-16's Yok AO32R's and rotary had 265-45-16 Kumho ecsta v700's. My car is missing AC, PS and ABS. My battery is in bin on passenger side whereas stock RX7 has battery in original position up front. Bottom line is mine weighed about 15 lbs more but had a better weight distribution of 50.5/49.5 front to rear and his stock RX7 was 53/47: --------------LS1 ------- Rotary Left Front: 684 ------- 718 Right Front: 695 ------- 718 Total Front: 1379 ------- 1436 Left Rear: 705 ------- 660 Right Rear: 645 ------- 618 Total Rear: 1350 ------- 1278 TOTAL: 2729 ------- 2714 % over Front: .505 ------- .530 % over Rear: .495 ------- .470 not a perfect comparison because i have some items remove/relocated, but it just shows it doesn't kill the handling or the weight distribution. the owner of the stock RX7 was my passenger on the last run; listen to his comments at the very end: http://207.127.219.37/video/AX.wmv My fastest time was 54.0 and his was 55.5. His tires (265-45-16 kumbo ecsta v700) were way better than mine (yok AO32R 245-45-16 Hard compound), no comparision. they were wider and stickier. My yok's are hard compound and are better on road courses than autocross. He is SCCA SS class driver that is original owner of the car, which is 93 R1. He races full season and competes in Kopeka, but this was my first autocross of the year!! and my first time ever autocrossing any RX7. He has stock R1 springs (stiffer than my stock non-R1 springs?) and $2000 koni custom valved double adjustable shocks (tripoint) and i have 13 year old stock units. The lack of ABS in my car definitely hurt my times as the video reflects constant right front tire lockup (dusty course, need new bleed because i just installed new master, need to adjust proportioning valve, who knows). He loved the car and how it felt on the course so that means a lot coming from a die hard rotary owner/racer. After that autocross, i had my car tuned on dyno: (IMG:http://207.127.219.37/images/rxdyno2.jpg) with the 2730 lbs curb weight and approx crank hp equalling 460 hp, i have lbs per hp ratio better than new z06 and viper: me: 2730/460 = 5.93 lbs/hp viper: 3470/510 hp = 6.80 lbs/HP C6 z06: 3147/505 hp = 6.23 lbs/HP