I am getting new wheels soon and have been seriously thinking about 15" wheels for faster acceleration and lighter weight. Does anyone have any hard numbers on how much hp loss there would be from a 34lbs a piece 15" wheel compared to a 38.8 lbs. a piece 17" wheel? Obviously the 17"s will look better, but I personally don't mind smaller 15" wheels, plus a 5 lb difference and smaller rotating diameter would help with acceleration. Anyone race at the track with one and then the other? What were your results?
Thanks for any help
Will
Larger wheels = larger rotational mass = slower acceleration (may not be much, but at a drag strip, 1 or 2 tenths makes a difference...)
Go with the 15's
Its the same concept for auto-x, the smaller diameter rims actually help.
if you get 15's they shoudl be a lot lighter then 38 lbs....or are you counting the tire to?
you will still have slower than stock acceleration. a 34lb 15in wheel is heavy. I don't think any stock j-body wheel weighs much over 20lbs
sorry the wieght was with the tires,
the wheels only weigh 14 lbs for the 15" and 19" for the 17" and the tires weigh ~20 lbs. either way...
38lbs with tires still seems high. I have 14's with drag radials, that are at 23lbs with tires.
FU Tuning
the 15's are 34 lbs with tires, if you had motegi tracklites which are 10lbs each and about the lightest wheel you can buy then that would mean your tires only weigh 13 lbs, I find that hard to believe.
The lightest 14" tire at tirerack weighs 14lbs, and has a width of 175... very skinny. then your wheels would have to weigh 9 lbs, which is totally possible but I would not drive around every day on something that ridicoulous looking. What exactly do you run?
My stock 15" steelies w/tire weigh 36.5lbs. My 17" Velox w/tire weigh 38.5lbs.
But you also have remember your moving the majority of weight out from the center which will effect acceleration and deceleration. It won't be much but it will be noticeable...
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My 15 '' mangles 8 spoke rims are really heavy for 15's compared to my stock steelies; i noticed a huge difference when putting on my 14 inch steelies with winter tires; feels more peppier now.
But i now want to go bigger and get some 17's.
Who makes a fairly light 17' and what is the style name?
98 j-body sedan
Will Paulman wrote:The lightest 14" tire at tirerack weighs 14lbs, and has a width of 175... very skinny. then your wheels would have to weigh 9 lbs, which is totally possible but I would not drive around every day on something that ridicoulous looking. What exactly do you run?
I'm runing drag radials, but that is only for the track, and they are not 175's.
FU Tuning
The absolute lightest 15" combo with, 205/60-15 tires would be tracklites (10 lbs.) and the lightest street tire I have found are Falkens ziex 512's(20lbs) that makes 30 lbs, so 34 doesn't seem to heavy to me, especially since the wheels I am getting are ~$60 each compared to tracklites ~$210 each, I'll take my $600 and 4 extra lbs. per corner and be happy.
So what kind of wheels and what brand of tire do you have?
The weight of the wheel has a very small effect on acceleration. The biggest difference is the diameter (as has been said). Most of the weight is in the barrel of the wheel, and as you move it out farther, there's more inertia to oversome. A lighter wheel will reduce unsprung mass, which is good for handling, If you took at 15x7" and a 17x7" wheel, both with 205's (say 50's for the 15 and 40's for the 17), that both weighed exactly the same, the handling would be almost identical, the 17's would be a little better because of more direct turn in due to less sidewall. Straight line performance, even if the 17" wheel weighed less, would be much different. For instance. On my Z34 many years ago I went from the stock 16x6.5" wheels and tires (225/60r16), weighing 51lbs, to a 17x8 wheel with a 245/45r17 weighing in at 49lbs, and I lost .3s at the track.
At the strip, smaller wheel is better, at the track, it depends on what you're comfortable with.
for autox though, the 15 with a smaller diameter tire will give you better acceleration out of the corner than a stock size tire.
my 05 cavalier does 15.2 bone stock with 14s
Some good light / cheap wheels are 15" Nippon F-2 wheels, they weight about 11 lbs each and cost about $300 a set.
- 93 mph in the 1/8 mile
Member of J-Body Of Michigan.
I've looked for those in a 5 x 100 bolt pattern and can't seem to find them anywhere.
i know with 15's traction was a huge issue for me... even before boost when I was heavily modified NA regular 15 inch tires would roast through second... I went with the stock wheel/tire combo and didnt have an issue and posted my BEST ET's NA
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