Best and cheap track wheels in 17x8

[diirk]

Originally Posted by JoeBoxer

I was impressed with the build quality of the dpt's but when I consider cheap I'd say no more than 600/set. I got something in mind will send u a pic shortly.

Looking forward to seeing what your idea is.....

[ayau]

Originally Posted by rice_classic

Can we talk about width and the law of diminishing returns for a moment?

Here's an example that played out a couple years back.

I race a 2250lb car with driver and 125whp. Max wheel size is 15x7" wheels. When this situation occurred we were running Toyo RA1's. Race distance is 30 minutes. Tried 205/50/15 and 225/45/15 back to back (no my car but identical to what I race). The lap times were the same.

To reiterate: The lap times were the same.

Now we didn't have data acquisition but when we discussed this with several other drivers and with race tire shops and veterans we discovered a few principles were at play, the first 2 being the most important:


1: Increase width = increase rolling resistance. This affects low hp cars more.
2: How the total size of combined contact patch (of 4 tires) correlates with the weight and speed of the vehicle in generating the appropriate amount of heat for the tire. Too wide of tire for too light of a car or too slow of a car means the tire will operate too cool and not produce optimal grip.
3: Increase width = Increase in rolling mass or unsprung weight.

Considering this car is quite light and only has 170whp it shouldn't be overly demanding of the rubber on top of the fact that unlike my FWD race car that over burdens the front tires this car will "spread the load" between all 4 (unless you're drifting which over heats the rears).

Last year I was discussing tire temps with a Hankook rep (BTW I love Hankook Z214 C51's!) and he told me that if I can't get the tire above 170F I'm "over-tired" and sacrificing performance and that I'd be faster running a slightly skinnier tire but in the 170-210F range to maximize lateral grip and I will also see a slight benefit on the long straights.

So I've said all that to ask this:

At what width do my lap times stop improving?

At what width does my total contact patch exceed my car's weight and power to generate appropriate temperature for optimal performance (if using that type of DOT tire)?

Or the transverse: I have a tire (like the Star Specs) that don't need a lot of heat so what width would I need in which I can run them as hard as I want for the entire session without overheating them?


Hope this helps.

you may find this thread interesting. it appears that wider does not equal better.

http://www.ft86club.com/forums/showthread.php?t=18443

[rice_classic]

Originally Posted by ayau

you may find this thread interesting. it appears that wider does not equal better.

http://www.ft86club.com/forums/showthread.php?t=18443

That's the point I was trying to make but more concisely... wider is better up to a point.

However I was discussing tire width and tire temperature as relation to over all grip (cornering force) while the thread you linked is discussing wheel width and how it applies to functionality of the tire excluding the concept of heat and the relation to power and weight of the car. So yes, thanks for that link as it's a separate topic but nonetheless related.

I have back to back race testing that says you don't need a wheel that's as wide as the contact patch, however it appears they make the point that if you can (such as if the rules allow) it's preferable to have a wheel that's wide enough to maximize the potential of the tire, which both accurate and logical. In most classes of competition you are relegated to a specific size wheel so over-tiring typically yields better results and as such is common practice.

Anyone notice that the wheels and tires in F1 and NASCAR are narrower than the wheels?... Interdasting.

It is fair, though, to keep in mind that not all tires are equal regarding their statements of size. Example: Hoosier over-sizes their tires.

A 205/50/15 Hoosier R6 is the same treadwidth (+/- 1/10th of an inch) as a 225/45/15 Hankook C51 or a Toyo RA1 (mounted). Running a 225 Hoosier R6 on my car ends up being too much tire because it'd be like running a 235 or 245 Toyo/Hankook and that's where I really run into the can't-make-enough-temp-to-make-the-tire-stick scenario.


Sorry for the threadjack since all my tire testing is done with DOT race tires as opposed to street tires.