Wheels size versus handling.

[old&slow]

Whats the general consensus regarding what wheel size handles better. Larger lower profile or smaller higher profile?

For instance if a guy wanted to maintain or improve a car that uses a 16 in 55 wheel, would he stay there or move to a 17 or 18 in lower profile tire.

Adding weight to the wheels obviously is not desireable but to what degree does it affect.

I have heard both sides argued but I' like to get opinions from this group!

Car in Question is a FWD Honda product !

thnx

[bundi]

I would guess that lower profile would give you better handling... allow me to demonstrate my thoughts with this incredibly detailed diagram.

The way I see it is that the shorter sidewall on a low profile tire is advantagous to handling because it's harder for it to be moved from side to side while turning etc since there's less space between a the ground and your rim.

Now.. I could be way off here, but I gave it a shot :D

[FiveFreshFish]

Lower profile is good but too low (large rim diameter) is detrimental to handling so maybe a +1 or +2 is as big as you should go.

[old&slow]

Originally posted by FiveFreshFish
Lower profile is good but too low (large rim diameter) is detrimental to handling so maybe a +1 or +2 is as big as you should go.


The question remains....maybe it's optimal now?
Going from 16 to 17 may actually impair handling!

[EK 2.0]

Sport Compact Car did a study of just this question on Rhys Millen's Evo a few years back.

It essentially detailed the difference of aspect ratio vs the added weight from larger wheels and tire combos.

The parameters were a 16, 17 and 18 inch Enkei IIRC. And essentially they found that even though the lightest set-up was the 16's it provided slower times around the Streets Of Willow Spriings due to the sidewall flex. The 18 inch wheel/tire combo was marginally faster than the 17 inch combo due to a 35 series tire on the 18 and a 40 on the 17. But they concluded that the added unsprung weight of the 18 inch combo was not enough to warrant the slightly faster times. So they concluded that for the Evo a 17 inch wheel/tire cmbo was best.

Having said that though, if a lil D16 powered Civic is asked to roll 17's the inital force required to spin those is much larger than a 16 inch combo.

Base the set-up on your car, on your power aspects...also take into account that if you end up using a real light wheel, TE 37 or a Slipstream or a Gram Light, the tires you choose should not be of the cheap Korean made variety. I mean then that way you are just negating the light wheel with a cheap heavy tire.




Originally posted by old&slow
The question remains....maybe it's optimal now?
Going from 16 to 17 may actually impair handling!


I would first set-up your suspension. Then decide on a wheel/tire combo...or even just a wider, lower profile tire on a the same size of rim...

[old&slow]

Originally posted by bundi
I would guess that lower profile would give you better handling... allow me to demonstrate my thoughts with this incredibly detailed diagram.

The way I see it is that the shorter sidewall on a low profile tire is advantagous to handling because it's harder for it to be moved from side to side while turning etc since there's less space between a the ground and your rim.


Now.. I could be way off here, but I gave it a shot :D


Yes that is the common belief but I have heard folks refute it!

Car has been lowered a tad!

[old&slow]

EK 2.0,

Thnx man....very informative!

Thats exactly what I was looking for!

Do you think adding 5 pounds per corner would be a large negative force?

[EK 2.0]

Originally posted by old&slow
EK 2.0,

Thnx man....very informative!

Thats exactly what I was looking for!

Do you think adding 5 pounds per corner would be a large negative force?

No worries but...

It shouldn't be, but if you are tracking the car lots, every pound of un-sprung weight lost will be an advantage in handling, braking, tire wear. Heck, if applicable even milage, not that that should matter on average track days. I am not going to pretend that I know the baseline that Honda engineered into the RSX...But basic lowering will not really enhance the handling of the car. If you want full out then a full coilover set IMHO is the way to go. You can adjust ride height (even though once you do it its pretty much set, and would require an alignment any other time you raise or lower it.) But the advantages are corner balancing. Also, stress bars, a lot of them are for looks, I think, but a good set of stress bars, Lower Tie Bars, anything to stiffen up the chassis first...then let the tires be your weakest point. As tires are easy to swap on, and research vs. handling traits of your chassis.

Once the car is set-up...take it to an open Auto-X day...see what you can do to improve your driving. For most times a lil track time is your best mod. And then decide if a larger wheel and tire combo is something warranted...usually you can get away with a nicer tire...instead of a whole new shoe package. But in all honesty, new shoes are HAWT!!...haha

[old&slow]

Lowering did help a bit but not a lot.
I added a beefier anti sway in the rear and it didnt seem to help much.
Never tried the Tie bar but i hear it does make a dif.
I put Bfgoodrich Geforce sports on the stock rims. There was some improvement.
Now I am considering 17" mostly for the lower profile.
Maybe I should just get spify 16 in rims???

I dont track at all. I just get a rush out of tight handling on ramps. I dont mind to spend a bit to increase handling and cornering performance. I'm not a racer!

Was considering that coilovers would be a good choice down the road when the shocks started to wear...but maybe I should consider them earlier...

[GTS Jeff]

The way to get the best of both worlds is to run small wheels with low profile tires. Your speedo will be off, but it enables you to benefit from the weight savings while having minimal sidewall flex.

The smart people at the track use 13" wheels with 50 series tires.

[percy]

A wide tread will offer better traction on hot, dry pavement - in all other situations, particularly on snow or wet pavement, the tire with the lower footprint will be better for normal driving, regardless of profile (i.e. narrow treaded tires are better than wide boots except on hot, dry pavement).

Low profile tends to create sideforce at lower drift angle so it makes steering and cornering more 'direct'.

Percy

[rage2]

A trick to reduce sidewall flex is to choose what width tires you want to run, then use the widest wheel possible as per tire manufacturer recommendation (not the stretch look, which is well over the manufacturer's limits). This will greatly reduce sidewall flex without adding a lot of unsprung weight.

[tom_9109]

Originally posted by GTS Jeff
The way to get the best of both worlds is to run small wheels with low profile tires. Your speedo will be off, but it enables you to benefit from the weight savings while having minimal sidewall flex.

The smart people at the track use 13" wheels with 50 series tires.

This works well except in the odd case where it causes enough of a gear ratio change that you drop out of powerband in some corners. You will definately accelerate faster but if it throws the ratio too far out can leave your great handling car lugging coming out of a corner. For those that want to say overall wheel/tire size doesn't affect gear ratio need to shhhhh now.

example of a stock car that has bad ratios, Newer Toyota Celica. They wanted better 0-60 so geared for it and the car is known to drop out of powerband in some corners on road courses. Where as if you take a stock Rsx Type S they didn't worry about 0-60 and made it so you had to shift into third right before 60. hurt their 0-60 times but in the real world made them win and they definitely hold their powerband in the corners.

[tirebob]

Lots of great answers for sure. It comes down to a lot of things over and above simply the tires and wheels...

If your car is civic is bone stock and you just throw on a big, heavy set of wheels and tires it will not benefit you, but on the other end of the scale, if you have a heavily modified car with gobs of power and a crazy super tight suspension, then the effect of the increased weight is minimized and the benifits of the lower profile, stiffer sidewall tire definitely shows through...

A stiff, short sidewall will not fold as much under extremely lateral g-forces, which in turn means that the tread surface is not lifting from the road surface, which in turn leaves a bigger contact patch which increases lateral traction.

This is assuming of course that we are comparing the same tire in the various sizes. If you have a shitty 225/40R18 versus a hardcore 205/55R16, the car would probably do a lot better on the 205/55R16.

There are tricks of course, as rage pointed out, stretching a narrower tire on a wider wheel (within reason of course) will improve the sideall stability during cornering etc. So many guys think that if they just put on a crazy set of tires they will be autocross ready, but without all the proper suspension upgrades etc you will not get the benefits out of a tire like that as your suspension will probably fold long before your tires would have ever broke loose.

Yes tires make a big difference, but people overdo it on a regular basis based on what they desire vs what they actually require...

[benyl]

Why does percy keep bringing threads up from 2005?

[tirebob]

Originally posted by benyl
Why does percy keep bringing threads up from 2005?

Haha! Just noticed that...

[JRSC00LUDE]

Originally posted by benyl
Why does percy keep bringing threads up from 2005?

Perhaps he exists on an alternate level of conciousness where the traditional boundaries of time and space do not exist?

[EK 2.0]

Originally posted by JRSC00LUDE


Perhaps he exists on an alternate level of conciousness where the traditional boundaries of time and space do not exist?



ooooo deep.:bigpimp:

[GTS Jeff]

Originally posted by JRSC00LUDE


Perhaps he exists on an alternate level of conciousness where the traditional boundaries of time and space do not exist? He's from another dimension maaaaaaaaaaaan...

[percy]

I registered just 5 days ago and this thing on tires was my first of two opinions sent in. Could benyl or tirebob enlighten me please on "what thread of 2005 I keep bringing up" Thank you.
Percy

[lianli]

This is one of them. :devil:

[old&slow]

guy uses a search and gets shit on? You can't win on Beyond!

[rage2]

haha don't worry about the haters, nothing wrong with bringing up an old thread with a topic you want to discuss lol.

[EK 2.0]

Originally posted by rage2

haha don't worry about the haters, nothing wrong with bringing up an old thread with a topic you want to discuss lol.


Agreed...especially when the topic is a good one...

[old&slow]

Originally posted by EK 2.0



Agreed...especially when the topic is a good one...

Maybe we need an age limit and a childish meter for those over the limit!:D :D :D

[hjr]

there is a good article on plus sizing in teh feb issue of 'grassroots motorsports'. quite informative. comes to the conclusion on a bmw 325i and zero, plus one, and plus two sizing. the conclusion was plus one was the best compromise and had the best times. (17" in that cars particular case)

[benyl]

Originally posted by percy
I registered just 5 days ago and this thing on tires was my first of two opinions sent in. Could benyl or tirebob enlighten me please on "what thread of 2005 I keep bringing up" Thank you.
Percy

Sure, no problem.

Here is the other post that you have made on the forum for a thread that was started and stopped in 2003.
http://forums.beyond.ca/showthread.php?s=&postid=2269699#post2269699

[benyl]

Originally posted by old&slow
guy uses a search and gets shit on? You can't win on Beyond!

Haha. You are the OP of the thread. Was his answer, 3 years later valuable to you? If so, that is great and I applaud him for finding your thread.

[tirebob]

Sorry bro... I didn't mean anything by that... Just I never realised that the thread was an older one... It is still a very relavent topic for sure!


Originally posted by percy
I registered just 5 days ago and this thing on tires was my first of two opinions sent in. Could benyl or tirebob enlighten me please on "what thread of 2005 I keep bringing up" Thank you.
Percy