wide wheels

[driftking777]

hey guys i know this has been asked a million times before, so sorry bout that...but I have only 7 1/2" wide tires and all i do 1st gear is roast tires...im looking for some wider tires (just for the back). wondering how well some 17x9 or so would fit...also what would be a good off set...would be for drag racing. And i dont want to roll the rear fender to fit really wide tires so...keep that in mind...wide tires, good offset...no rolled fender...thanks guys

[Hit_N_Run-player]

ive actually heard that wider tires doesnt actually help for traction, ill find the link for it somewhere...

[logik23]

Originally Posted by Hit_N_Run-player

ive actually heard that wider tires doesnt actually help for traction, ill find the link for it somewhere...

I think it's handling that they don't improve, but I'm pretty sure it's harder to smoke foot wides then 7 inchers.

[Hit_N_Run-player]

aha, here it is

-----------------------------------
Q: For us non-physics guys, please explain F=uN.

A: F, the forward force that accelerates your car, is the product of "u", which is the traction coefficient for a given pair of materials (in this case rubber on asphalt) times the "downforce" ("N") of the drive wheels on the road. The width of the tire is never in this calculation. The only reason wider tires can help is they can increase the "effective u" just a little, not a lot.


Wide tires are far more "show" than "go," no matter how much our egos want to disagree with that. The bottom line is g’s, and we’ve done a lot of testing in this area. The data should speak for itself, and correspond to tests on the street. Track conditions are typically better. The lowest traction limits we’ve measured are all on front-wheel-drive cars. This is because of the weight transfer offthe drive wheels when accelerating. They’re always between .40g and .50g.

Rear-wheel drive vehicles fare better. Most pickup trucks generate between .48 and .52g, thanks to in-optimized weight distribution. Non-posi cars are again a little better. They typically generate a maximum of .50 to .55g almost every time. We tested a Ford Crown Victoria with 215mm rubber, and it would spin the right rear at .50g. Next test was a ‘66 Mustang Coupe with 195mm rubber, which spun ‘em at .53g. A Volvo wagon (195mm tires) spins the right rear at .55g. This Mustang Fastback, with a posi and BFG radial T/A tires (215 mm) pulled .54g before the changes, and with the battery in the trunk now pulls .55 to .56g. Grand National Buicks (with posi) usually got .55g, 5.0L Mustangs (225mm, with posi) get .56 to .59g. My friend Rich has a ‘69 Super Bee, good posi, 215mm BFG’s, and pulls .57g before they spin. Note that these are not big differences from the best to the worst!

Now for some wide tire data: my friend John has a ’66 Nova with 275mm rubber and a good posi, yet it pulls .53 g max, right in there with my skinny-tired ’66 Mustang. Rich also owns a Hemi Charger with 275mm rubber, which can’t generate more than .55g, which you’ll note is less than his Super Bee does on 215s. That’s because he has played the weight distribution game on the Super Bee.

Highest street tire numbers ever? Weight distribution is a player. New Z28s (245 mm) commonly pull .62g max. My friend Shirl has a ‘79 Corvette (245 mm) pulls .65g on street tires.

See where I’m going here? There’s no magic "factor of two" yet. Honestly, even a posi only seems worth .05g or so (10 percent). How many guys do we run into that think a posi will double their traction?

Want to see big improvements? Change the tire compound. My friend Dave bought some BFG Drag Radials for his 5.0L Mustang. His 225mm street tires spin at .59g every time, yet his 235mm Drag Radials consistently pulled .68g. That’s 15 percent! A co-worker brought in his NSX with 245mm race tires, and thanks to the combined help of its mid-engine layout, we were measuring .75 g launches, over and over again!


I’m not saying that wider tires would hurt, I’m just arguing that they’re far more for show than go. They wouldn’t double the traction. Or add 50 percent, or even 25 percent. The max we’re talking is probably under 10 percent. So without tubbing the car, I can probably squeak in some 245mm tires if I had to. By trying to play the testosterone factor low on this car, my best money will go towards a set of drag radials, and selectively moving weight to the rear, not tubbing the car and running 315mm street tires.
------------------------------------

I copyed that straight from this page, read it all its kinda help full, i copyed it from this turbo section... http://www.automotiveforums.com/vbul...d.php?t=201348

then scroll down to the third post with the interview!!

[Hit_N_Run-player]

you could do it as maybe a cosmetic upgrade, and you'll see if it actually does help then we could prove that guy wrong (bill watson)lol

[logik23]

Ok, why don't the top fuel guys have the skinnies all around?

[Hit_N_Run-player]

idk, im just posting the info i found, plust top fuel dragsters are probably putting out a little more power than a 2.0litre 4cyl...but the material i think also matters, buy em for looks and see if they really work....if you think about it wider tires would make more sense but this bill guy puts up a pretty good argument!

[S13wanabe]

Wider does make for better traction. Although pounds per square inch is made less of the contact patch with wider tires, the contact patch is bigger. This has a greater effect on traction. That's why they put limitations on tire width on drag cars and other race cars. Tire compound does have a great effect though too. Before I would go otu and buy new rims, try a better tire. Falken makes the Azenis Sport for that size wheel and they have been good to me. They are an auto-x tire so they have a very stiff side wall (not great for drag racing), but they handle real well and they grip pretty damn good on launches too, if they break loose it just creates some pretty violent wheel hop. They suck in wet conditions though. Just try investing in some good tires though. They make all the difference in the world.

[driftking777]

i thought i had some pretty good tires as it was...nitto neo gens...pretty sticky tires...no there no BF goodrich comp ta drag radials..but for driving around there pretty sticky. i also dont want to sticky of tires on my stocker rims becuase tire wear...im wanting to get wide rims with sticky tires for the drag...not driving around on.

[AWDSR20]

LSD, LSD,LSD
AND wider tiers give better traction F=uN is teh wrong formula buddy!!!, more like its a smal factor in the whole pictue. the larger the surface teh better is the grip...


ALSO the compound the tire is made of is of great important!!!!

many factors goz into spinig tiers, there is no one eq that puts it all together.

[Hit_N_Run-player]

Originally Posted by AWDSR20

LSD, LSD,LSD
AND wider tiers give better traction F=uN is teh wrong formula buddy!!!, more like its a smal factor in the whole pictue. the larger the surface teh better is the grip...


ALSO the compound the tire is made of is of great important!!!!

many factors goz into spinig tiers, there is no one eq that puts it all together.

hotrod magazine is just randomly posting shit in there mags that are wrong? why the hell is everyone so ignorant around here? what makes it wrong and how do you know? Do you have a twin turbo mustang that runs 10's?? or was that guy just knowing nothing about it and making all those physics and everything up.... Think outside the box guys...

[fishlips34]

The grip produced by a tire is load dependent. The more load on the tire, the more grip it will be able to produce. For example, take a winged and a non-wing sprint car. The Winged car is faster because it has the wing on top producing more load downward on the tires. I do agree with his formula but theres more factors that just that. lets say I have rear wheel drive and put lets say 300 pounds in my trunk and lower my tires presure I would have a much better pull(g lunch) But if you'll notice these are all street tires they tested not DOT slicks. So in awser to your question driftking I would get a set of slicks for the track and a piar of tires that last awhile for the road just my two cents

[fishlips34]

Just an aditive here. Have you ever seen a picture of a drag car when it launches? and what the tires look like? The rubber that tires are made of is viscoelastic. This means that they are able to deform, and recover to their original shape. it takes the tire about a ½ rotation to recover to its original shape. Street tires are made just for that the street but slicks are made to "roll". Insted of just spinning it deforms the whole tire and as the tire tries to recover back to its origanal shape its actually producing more forward thrust and not just spinning reling on pure horse power to do the trick.

[k3smostwanted]

Originally Posted by Hit_N_Run-player

I copyed that straight from this page, read it all its kinda help full, i copyed it from this turbo section... http://www.automotiveforums.com/vbul...d.php?t=201348

then scroll down to the third post with the interview!!

really, i cannot grasp his theory and proof with open arms. think about it...not once in that whole argument did he use the same car and the same tire (but in different widths) to show the whole difference that the width made. for an experiment to be believable and hold any good information, you have to control as many variables as possible. he compared different cars to different size tires. all the different cars have different suspensions, different sized tires, different weights, some had posi, some were open. WTF...

really instead of writing all of that crap. all as he had to do was take one car. put size of tire "A" on first, see how many G's it pulled. then take the same compound and brand of tire just in a wider tire size of "B" and then see what it did.

[publicenemy137]

Originally Posted by k3smostwanted

really, i cannot grasp his theory and proof with open arms. think about it...not once in that whole argument did he use the same car and the same tire (but in different widths) to show the whole difference that the width made. for an experiment to be believable and hold any good information, you have to control as many variables as possible. he compared different cars to different size tires. all the different cars have different suspensions, different sized tires, different weights, some had posi, some were open. WTF...

really instead of writing all of that crap. all as he had to do was take one car. put size of tire "A" on first, see how many G's it pulled. then take the same compound and brand of tire just in a wider tire size of "B" and then see what it did.

Why would he need to bring out different cars for, each cars have different suspensions and traction issues. All he needed to do was use one car and test the difference of tires and width.