Team Chevelle banner
1 - 17 of 17 Posts

·
Registered
Joined
·
418 Posts
Discussion Starter · #1 ·
I'm running 15x8s all the way around with 245/60R15s on the front. The car goes 12.60s at 108.xx at the moment. If i were to get some lighter aluminum wheels and put skinnies on the front, how much time would that get me? any clues? thanks

roger
 

·
In Memoriam
66 El Camino 57 Chevy pickup 2004 Tahoe
Joined
·
29,419 Posts
might want to weigh the aluminum wheels to see if they're actually lighter. some aren't.

I doubt any difference between the rotating weight of the different rims is impacting your times. Think of how small this is in relation to the car weight.
 

·
Registered
Joined
·
418 Posts
Discussion Starter · #3 ·
yeah the car is a full weight chevelle. i think the last time i went from regular tires to pizza cutters on the front i dropped a tenth. that was with a different motor and an automatic trans and i was running low 14s.
 

·
Registered
Joined
·
250 Posts
If you went from 4-15x8 steel wheels to 2-15x8 and 2-15x5.5 forged wheels I would say a solid tenth to 2 tenths...billet aluminum would be slightly less.

Don't forget this is unsprung weight. ;)
 

·
Registered
Joined
·
418 Posts
Discussion Starter · #7 ·
502 can you explain 'unsprung' weight. i kind of get it but wouldn't mind having it explained to me.

wouldn't there be two variables, the weight added to the vehicle, and the extra work necessary to rotate a heavier object?
 

·
Registered
Joined
·
418 Posts
Discussion Starter · #8 ·
rotate the rear wheels that is, and and less wind resistance with pizza cutters on the front.
 

·
Registered
Joined
·
14,625 Posts
I weighed my tires when I went from 15x7 with 205x75x15 and 15x8 with 275x60s. To my centerlines drag 05. I had the same size tires put on the center lines, rim size is 15x3.5 and 275x60. I saved 64 pounds. I dont know if this helps Jim
 

·
Registered
Joined
·
203 Posts
Chev-man, I Just Did A Comparison Of Different Wheels And Tires On The Front Of My Chevelle. I Have Been Running Cragar Street Star Chrome Steel 15x6 With 26" Tall Street Tires And I Weighed Them. They Weighed 45lbs. Each, So 90 Lbs. In Front Tires And Wheels. I Borrowed Billscamino's Front Skinny Weld Racing Aluminum Wheels With Hoosier 28x15x4.5 Racing Tires Mounted On Them. These Wheels Look Identical To My Chrome Wheels But They Are Aluminum. His Wheels With Tires Mounted Weighed 20lbs. Each Or 40 Lbs. Total For Front Wheel And Tire Combos. So If I Got The Same Setup As Bill I Would See A 50 Lb. Weight Loss Off The Front End. Will Be Going To Test Bills Tires And Wheels At The Track Soon To See How Much They Help With My 60' Times And E.t.'s. Maybe This Will Help You.
 

·
Registered
Joined
·
418 Posts
Discussion Starter · #12 ·
Laughing Rat

Nice, let me know how you make out.
 

·
Premium Member
Joined
·
7,278 Posts

·
Registered
Joined
·
1,070 Posts
If the same size (diameter) front tires are not used the test will really not be valid. A shorter front tire will give a deeper stage and a slower et. A tall tire will have the same effect as shallow staging and show a slightly faster et.

I had a car with 28" front tires. There was a tenth et difference from shallow staging ( barely bumping on the light) to deep staging(putting out the top bulb). The shorter the tire the less difference you will see. This was with a high 9 second car.
 

·
Registered
Joined
·
418 Posts
Discussion Starter · #16 ·
art, nice article. thanks for posting it. definately don't feel bad about keeping the rallies on.:beers:
 

·
Registered
Joined
·
1,889 Posts
I'd say rolling resistance has alot to do with it, swapping to radial slicks was worth .08 in ET on my car, and they were 4lbs heavier then the tires i took off (total).

If your car weighs 3900lbs, 100lbs is 2.49% of the total
If your 2300lbs, its 4.3%
And if your a dragster and weigh 1700lbs, its 5.9%

So i'd say its nearly impossible for 100lbs to effect every car the same.
 
1 - 17 of 17 Posts
Top