17 or 18? Light weight?

ruchi · Post by **ruchi** » Fri Jul 30, 2004 10:40 pm

remember there will also be a cost difference between tyres for 17" and 18" rims.

D-TRAIN · Post by **D-TRAIN** » Sun Aug 01, 2004 4:56 pm

Guni_GuGu wrote:How much of a difference, do you think we're talking about in power with regards to the weight difference between the stock 16", to something like ~9kg 18" (without tyres) so add in an estimated weight on the tyres too??

Have any of you with 18's lowered your car?

If you can get 18"s that weigh 9kgs, you're doing pretty well for yourself.

I think 17"s are just right, with some lowering springs.

I've got 17" OZ Superleggeras and they weigh 6.5kg each without tyres. They definately feel lighter than the stocks.

I've also asked Momo how much their 17's weigh, and was told just above the 10kg mark.

RallyMad · Post by **RallyMad** » Mon Aug 02, 2004 6:54 pm

Guni_GuGu wrote:How much of a difference, do you think we're talking about in power with regards to the weight difference between the stock 16", to something like ~9kg 18" (without tyres) so add in an estimated weight on the tyres too??

I would think that you won't lose or gain power from going to a larger wheel. What you'll get is handling improvements with a lighter rolling mass, and maybe better grip with lower profile tyres. But I think mostly you'll just get a sweet looking ride

Guni_GuGu · Post by **Guni_GuGu** » Tue Aug 03, 2004 12:59 pm

D-TRAIN wrote:
Guni_GuGu wrote:How much of a difference, do you think we're talking about in power with regards to the weight difference between the stock 16", to something like ~9kg 18" (without tyres) so add in an estimated weight on the tyres too??

Have any of you with 18's lowered your car?
If you can get 18"s that weigh 9kgs, you're doing pretty well for yourself.

I think 17"s are just right, with some lowering springs.

I've got 17" OZ Superleggeras and they weigh 6.5kg each without tyres. They definately feel lighter than the stocks.

I've also asked Momo how much their 17's weigh, and was told just above the 10kg mark.

I remember reading, that Momo's were actually very very heavy.

Still not sure, which way i'm heading though... 17's lowered sounds good, but, won't they're be some issues with rubbing? I'm really keen on some 235/40 or something about there....

Then again, I think the fto will look soooo shilick with some big ass 18's on em...

-------

For RallyMad:
Since the wheels, are very likely to be heavier, for power is needed to drive them, thus, I'd have to most definantly believe, it would reduce the power at the wheel on the fto.

Remember those dyno's some of you guys did at UAS, how did ya'll go with the different size rims?

RallyMad · Post by **RallyMad** » Fri Aug 06, 2004 7:27 pm

Maybe your right there GUni-Gugu but I would think the effect would be marginal.

And as the old arguement with dynos go it would be hard to compare the power figures from a car with 17 vs 18's becasue it would depend also on the tyres they had, what psi, wear, etc.

Sorry for being picky and I'm not trying to be arguementative either but I feel your looking to much at trying to earn power out of something which I think is mostly cosmetic while giving some benefits to traction, but then again as has been pointed out to me, F1 run fine on 13's don't they? Be it that they are crazy light magnesium wheels still.

I hope you find some wheels you like though mate

ruchi · Post by **ruchi** » Fri Aug 06, 2004 8:54 pm

OK, lets clear a few things up...

Firstly the weight to consider is the overall tyre & rim combo, not just the rim by itself.

Secondly, by altering the weight of the tyre & rim combo you will alter the inertia of the wheels not the power of the car.

Inertia is the ability / inability of an item to change motion, the lighter a wheel is the easier it is to change its motion while the heavier it is the harder it will be to change its motion. This also applies for any other turning items on a car such as flywheel, pulleys etc.

Like most things with cars it is a matter of getting the right balance and tuning it to the way you want it, it is not a matter of less inertia is better and more is bad. While lower inertia will allow the car to accelerate faster, it also means that those items which turn (wheels, flywheel, pulleys etc.) will have less momentum and will not be able to maintain the speed at which they turn when you take your foot off the accelerator. This means that revs will fall faster, making it harder to stay within the powerband range and in extreme cases can also lead to an increase in stalling (the stall point rises).

Probably the most important issue relating to the weight of the wheels is that of suspension and handling. Rather than going through it all again let me point you to another topic that covers this:

http://www.ftoaustralia.com/modules.php ... pic&t=2696

RallyMad · Post by **RallyMad** » Sat Aug 07, 2004 1:42 am

Thanks for that Ruchi, that was what I was trying to say

MrFT000 · Post by **MrFT000** » Wed Aug 25, 2004 12:39 am

Enkei's are good rims if you can afford to dish out the cash.
lightweight, look good and overall a good quality rim.
but again - $$$$$

D-TRAIN · Post by **D-TRAIN** » Sun Nov 07, 2004 10:06 am

Those interested in light weight rims, check out this site, if you haven't already have:

http://www.wheelweights.net/

Go O.Z.!!