Hey guys im looking to buy new wheels for my v6 sports coupe, i have the money to get 17" rims, but im wondering if there is actually a performance increase the bigger the rim you get? Just thought i'd ask if anyone had any opinions on this for me. I was thinking of getting 17" chrome torq thruster hehe. well give me ur input guys, i apreciate it.

 

Wheels have three opportunities to improve performance...
1. Reduction of unsprung weight

2. Increase strength

3. Support of advanced tire designs

Mostly, aftermarket wheels don't do 1 or 2 unless you
have serious money. Three well three is a great debate
as you are moving in a very specific direction with
very specific tradeoffs. That is you don't discuss the
merits of drag radials and autocross tires in the same
conversation.

If you are looking for a performance increase decide
carefully what that neans to you (drag racing, auto cross,
solo1 etc) Then look at what kind of rubber you need to support
that sort of fun. Then check your wallet and see if you
can support better wheels in addition to the speciality
rubber.

 

hmmm, so basically getting 16 or 17" wont make a differance unless its made specifically for a specific such as drag racing or something? I was looking into American racing AR136's in 16" but if 17" increased performance i would get differant wheels.

 

can you give me a example of the "serious money" wheels and what they cost? like maybe a pic of the performance wheels?

 

The larger the rim, the less sidewall on the tire of the same heights.

The only performance gain would be in road course type racing. With a very small sidewall, the tire won't roll over on hard turns. For drag racing you want a tall sidewall. That's why the majority of drag tires are for a 15" rim.

 

ahhhh, thankyou, thats what i wanted to know, i apreciate it.

 

id say for a everyday street car its better to have a slightly shorter sidewall...because on the street having alot of sidewall really wont give you much more traction. unless you deflate the tires but that isnt really safe. id say go with a 16x8 TT II i wouldnt get chrome...i got the polished ones and they are shiny enough. i put a set of z rated dunlops on them...245/50/16...looks killer.

 

i went from the stock 15x7 to ROH 17x9 and the difference in performance is astronomical. Bigger wheels allow for more rubber which equals more of your car on the road. I gained two inches of lateral rubber on the road by going to a wheel that was 2 inches per wheel wider than stock. So if you go to a wider wheel than stock your answer is yes. You will see a big difference in performance.

 

The larger the rim, the less sidewall on the tire of the same heights.

The only performance gain would be in road course type racing. With a very small sidewall, the tire won't roll over on hard turns. For drag racing you want a tall sidewall. That's why the majority of drag tires are for a 15" rim.


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UM... I HAVE A FRIEND. HIS 92 NSX HAS BEEN DROPPED1.5" AND HAS 17 AND 18" MOMO WHEEL COMBO. I HAVE HEARD HIM SAY SEVERAL TIMES THAT JE NEEDS TO GET SMALL RIMS TO SUPPORT MORE SIDEWALL IN WHEEL WELLS SO THAT HE CAN GET MORE TRACTION. NOW THE WAY HE EXPLAINED IT WAS THAT WITH A SHORTER SIDEWALL THE TIRE HAS LESS FLEXABILITY AND THEREFORE WITH LOSE TRACTION ON THE TRACK IN HARD CORNERING SITUATIONS. SO WITH MORE SIDEWALL THE WHEEL WILL ROLL ONTO THE SIDEWALL AND KEEPING TRACTION. DID THAT MAKE ANY SENSE? THIS IS WHAT I HAVE HEARD. BUT HE SAYS THE CAR RIDES AS IF IT WERE ON RAILS NOW WITH THE COMBO BUT FOR MORE TRACTION ON THE TRACK HE NEEDS THE SMALLER WHEEL TALLER TIRE COMBO. I DO UNDERSTAND THAT FOR DAILY CITY DRVING IT DOESNT REALY MATTER. BNUT WHEN IT COMES TO THE TRACK OR AUTOCROSSING DOESNT THAT MAKE SENSE?

 

khellendros, nice name..
kitiara, rastlin, flint, mayls, etc ring a bell?

 

yes of course, dragonlance characters =p, gotta love the big blue storm over krynn haha.

 

Your friend is an idiot. When a tire rolls over on the sidewall, the full tread footprint ( traction area on the tire that is intended by the tire manufacturer to remain in contact with the road) is no longer making contact, thus causing loss of traction. This is not brainsurgery. Take a bottle of white shoe polish an mark aprox. a 3" mark along the inside and outside of the tires. Now make a run on on a roadcourse and then check the polish marks to see how much was scrubed offover the edge.

If inside and outside do not touch the edges evenly- reduce tire pressure

If inside and outside scrub marks off over the tread edges evenly- raise tire pressure.

If over the outer edge but not to the inner edge-Add negative camber.
Opposite of this-add positive camber.

The lower profile and better yet stiffer sidewall will improve cornering. I would perfer a stiffer but little higher sidewall over a lower profile cheap quality tire. You get what you pay for/ dont skimp on tires.

 

well. somehting has to give when u are cornering hard. traction or the sidewall of the tire? I mean think about it. when u are cornering hard something has to give. do u want it to be your traction to give b/c u put on a stiff and short sidewall tire to tighten up the handling? or do u want a little flimsier and taller sidewall to give a lttle therefore keeping traction? It seems simple to me but maybe a little harder for you to grasp.

 

you will not gain traction by having the sidewall roll , what will happen is this

you are cornering really hard, the sidewall rolls over , the contact patch of the tire is now smaller, you lose traction. the key to this all is the contact patch of the tire, when it rolls over your contact patch will get smaller as less of the tire is on the road. when this happens you lose more traction. if wider sidewalls helped, don't you think we would see racecars with larger profile tires. look at the le mans cars, they have almost NO sidewall whatso ever and the pull 1.8 lateral g's all day long.

 

I was reading the new issue of Camaro Performers this weekend.
In this issue they have an article called "Big Wheels Turning",
where they proceeded to test different rim an tire combos on a
first gen camaro. They tried the stock 15x7, 16x8, 17x8, and and
18x8-20x8 combo. From my knowledge it is known that increasing the diameter of the
rims and decreasing the sidewall of the tire will deliver increased
lateral g's. This is due to two things, decreased sidewall flex and
also increased contact patch from the increased treadwith of the
tire. If you take a 255/50/16 verse a 255/45/17 the 17 inch tire
will have a tread width which is larger by about 0.2 - 0.3 inches.
Now although larger rims (18-20's) do provide more higher lateral
g capabilities, it must also be noted that the ride becomes much
rougher. More importantly to handling the shorter sidewall and
less flex also results in less consistent and predictable handling.
Although, they can run the slalom at faster speeds you are
really riding on the edge and when you lose grip you really lose
grip, I think that is what your friend with the NSX is talking about
STREETRUNNER.

Now if you are going to be running your car on the street I think
a 16 or 17 inch tire will be fine for performance. The 17's will
provide better cornering and visual appeal depending on what you like, but I
feel that for street duty you do not NEED 17's for handling
purposes.

Good luck making your decision and I hope I helped

 

Nazzz28 sumed this up very well.
However, I just love when some 16 yr old punk thinks she knows the world and arrogantly tells me that he grasps something and I don't. Put your Frikin Mommy & Daddy's money where your mouth is kid. I own, set, and race a Championship modified Vette in the SCCA, But I can beat you in a Pinto. You are old enough to no what a pinto is, don't you?

 

Talk is cheap, here it is.

 

Thats the first thing I thought when I seen his name also.

My brother uses Khellendros as a handle online

 

also with the tire rollover isn't possible to strip the tire off the rim in hard cornering? If that happened you better kiss your A^% goodbye cuse your goin for a rollercoster ride if ya know what i mean.......now i don't know how likely that is but it happened to a kid when i was in highschool years ago and guess what.....he didn't grow up.

 

I don't know that it would be likely unless you had a relatively tall sidewall on a 14" or 15" rim and a crappy tire. Even then, I think it would be extremely difficult to rip a tire off. However, when a tire rolls over you risk damaging the tire. I wasn't running enough tire pressure at an autocross and too much of the tire rolled over, and it caused feathering all along the edge of the tire.

 

look at the F1 cars they have the biggest profile tires in the world and look at all open wheel racing they all have tall tires. then look at nascar which is the closest besides trans am racing that u get to american cars reely racing they have tall profiles as well.

 

Next time a NASCAR race is on, watch and look for the wheel/brake camera shot. The taller tire's flex, allow's the contact patch of the tire to stay level to the racing surface as the car leans on it during a turn. I'm no rocket scientist. but it seems that a lower profile tire would have a tendancy to break loose during heavy lateral loads. Just my .02

 

thankyou. exactly what i ahve been trying to explain.

 

Lilred383 thats what I was saying. Although, extremely low
profile tires can accomplish high lateral g's, when you are pushing
them you are riding on the edge. What I'm trying to say is that
when you break loose and loose grip you really loose grip. 16
and 17 inch tires have a sidewall height that allows for more
predictable handling, and you can kind of tell and feel when you are
pushing them to there limit before you loose grip.

 

Yeah but arn't the nascar and F1 Tires made alot different than street tires? Much Stiffer Sidewalls and such? Most street tires that i know of have what 2 ply too 3 ply on the sidewalls for performance tires and 2 or less ply for normal tires...How many belts do Nascar tires have on the sides? i bet its more that that infact isn't the Goodyear runflats made with F1 Tire tech? I could be wrong and please correct me if i am but Tires for those cars and our cars are much diff as they are designed for a completly diff use.

 

OK, i *think* I can explain all this from reading this post, and from my basic cognative abilities...

There are currently 2 arguments here.
1: Sidewall flex allows tire contact patch to remain in contact
2: LACK of sidewall flex allows tire contact patch to stay in contract

Now, one fo you is wrong. But not totally. It is farily well proven that on street type tires (EG: NOT Nascar tires or CART tires..), a lower profile helps cornering. I will not dispute this because it makes sense. I used to run 225/65 Michilen Pilots on my car, I switched to 235/60 Radial T/A's. Now, the T/A's suck IMO because, I *think* the tire is a little to wide fer my stock 15" rims. I *know* that the side wall flexes quite a bit from when I check my ball joints (puch and pull of tire, ya know...). Straight line trction stayed the same because *I think* The conctact patch is being pulled askew.

So, to get back to the arguement. What is being said about larger sidewalls, is that they are more forgiving, as you will start to slip less severely when you start to skid than with low profile tires. Lower profile has a tendency to hold more load (just look at the physics - less strength is required because not as much flexing stuff, i am horrible with words - sorry). BUT, when they start to skid, they skid worse. This could possibly be just because of the higher load, or the actaull tire physics.

Alright - I took a shot at this. What does everyone think? I missed something(s), i know - point it out (cuz I dunno WHAT i missed)!!

 

well since everyone is explaining what they meant by what they said i will as well. i was saying that the taller sidewalled tire is more forgiving and will allow a less expierienced driver to drive hard. The shporter and tighter sidewalled tire will give you better handlin but when u push it too far it goes away and much worse than a (more forgiving tire). So what my friend meant by saying he needed a smaller rim combo so he coule run larger sidewall tires was so that his car would be more forgiving around the corners on the track so that he could run it hard and not worry about hurting his baby. dont get me wrong that thing is on rails with his 215 30 17 up front and 255 30 18 in the rear on the momo rims.

 

but whenever you do something to a car theres a always a drawback. and a compromise always there as well it juss depends on wheter the advantage is better than the drawback

 

F1 and NASCAR are both limited to a certain diameter rim and tire, that is all they are allowed to run. If they could, THEY WOULD RUN LOWER PROFILE TIRES. Next time F1 is on, you will notice tread or grooves on the tires. This rule was put into effect to lower grip because the cars were pulling to many g's in the corners causing severe fatigue on both car and driver. If they could run lower profile tires, the cars would corner hard enough to make the driver black out from the g's, thats how well those car stick to the ground.

Now the facts. If a taller sidewall tire will corner at 80mph and then break traction forgivingly, you may enter the corner at probably 82mph and maybe save it but scrub of time. A stiffer/ lower profile tire can take that same corner at 90mph and then spin without notice, but if you enter at 85mph- then no problem. You run faster with room to spare. Just learn the limits of your car. How? By practicing. (in wide open spaces I might add.)