wheel gap?

[danFromNYC]

What is the best way to fill in the gap between the tire and wheel well? I have noticed on some Daytona builds, the body' stance doesn't look right ( my taste, I like a meaty tire in front and rear). Thanks.

[Eyesore]

The tires used on 15" wheels are larger in diameter than the tires used on 17" wheels. (I know, sounds backwards) The combination of a 15" wheel and tire package and the proper ride height will fill the wheel wells nicely.

[GThompson]

Goodyear Billboards fill the wheel wells nicely.

http://i183.photobucket.com/albums/x213/ffrgorgo/photo_zps6defaa74.jpg (http://s183.photobucket.com/user/ffrgorgo/media/photo_zps6defaa74.jpg.html)

[Garry Bopp]

Dan,

I run 17" pin drive wheels and to get a nice looking stance you have to run a pretty low ride height. Mine are set at 3.75" from the frame rail to the ground. Have to be careful over speed humps and steep driveways ... bell housing will drag.

Here are some pics I took several months ago. Tires are Kumho Ecsta XS 275X17 front and 315X17 rear.

Garry

http://i142.photobucket.com/albums/r102/theboppshop/CoupePicsMay2013014_zps17c4ebe8.jpg (http://s142.photobucket.com/user/theboppshop/media/CoupePicsMay2013014_zps17c4ebe8.jpg.html)

http://i142.photobucket.com/albums/r102/theboppshop/CoupePicsMay2013007_zpsbef3431f.jpg (http://s142.photobucket.com/user/theboppshop/media/CoupePicsMay2013007_zpsbef3431f.jpg.html)

http://i142.photobucket.com/albums/r102/theboppshop/CoupePicsMay2013013_zps9f8987fe.jpg (http://s142.photobucket.com/user/theboppshop/media/CoupePicsMay2013013_zps9f8987fe.jpg.html)

http://i142.photobucket.com/albums/r102/theboppshop/CoupePicsMay2013009_zpsb3ab76b2.jpg (http://s142.photobucket.com/user/theboppshop/media/CoupePicsMay2013009_zpsb3ab76b2.jpg.html)

http://i142.photobucket.com/albums/r102/theboppshop/CoupePicsMay2013011_zps935a3edf.jpg (http://s142.photobucket.com/user/theboppshop/media/CoupePicsMay2013011_zps935a3edf.jpg.html)

http://i142.photobucket.com/albums/r102/theboppshop/CoupePicsMay2013008_zpse4b60a9f.jpg (http://s142.photobucket.com/user/theboppshop/media/CoupePicsMay2013008_zpse4b60a9f.jpg.html)

[Doutie]

Garry,
Nicest Daytona I've seen yet. It's S. Twain awesome!!!!!!

[tirod]

Everyone likes wheel wells filled with tire.

On the other hand, it's new era. It wasn't even possible when they actually raced in the day. I use this pic as wallpaper: http://www.ultimatecarpage.com/img/304/AC-Shelby-Cobra-Daytona-Coupe.html

Not much tire on that? It's basically a matter of perspective. In the day, those are huge compared to the 7.25x15's on Dad's Buick wagon. Eight and nine inch tires, the advent of 50 series, etc. all offered a lot of rubber for those who wanted it. N50-15's on the back of a 69 GTO were enormous.

Now it's passe. Anything less and we comment about someone's masculinity. Tires filling the wheel well didn't happen for the originals, and they won a world championship regardless. It was all about horsepower to weight ratio, handling, and having a bullet proof drive train, which SA had to earn.

There's also some crossover with other forms of racing. Since the invention of the drag slick, really huge tires seem to be the goal - and yet road, autocross, and LSR cars don't. There are other factors, like, unsprung weight. Larger rims are usually a pound more per inch in diameter. A set of 17's with rubber on the usually weigh at least two pounds more per wheel than 15's - even with the heavier 15" tire. That means they have more rotational inertia - it takes more power to spin them up to speed - or slow them down.

Track testing shows that without the huge brakes that started the whole point of larger rims, a car actually has better 1/4 mile times with 15's, smoother ride quality, and more durability on poor roads. The only advantage of the larger rim and low profile tire is an incremental increase in cornering power. Considering the complete lack of development a lot of kits never see to maximize shocks, spring rates, and tune sway bars, the tires are nearly insignificant.

The only problem we have is that the makers have abandoned the 15" tire and there's no choice in the matter these days. Since we are left with all the negatives of a larger rim with very little contribution, I see it as even more compelling to get the chassis and suspension set up than worry about the image of what's in the fenderwell. They are going to wear out in a few years anyway.

Build it the way you want, there's more to it than looks. Just be aware of the results of decision making so their are no unintended consequences. There are a lot of little pitfalls in choosing rims, tires, backsets, pin drive or not, etc.

[Garry Bopp]

Tirod,

As you say, build it the way you want it. It also depends on what you plan on doing with your coupe. If it is mostly street driving with limited track time (that's me), then go for whatever look you want, within reason. If you are running track only, that's a much different type of build and "how it looks" is certainly secondary to chassis development. My car rides and drives beautifully (IRS), as numerous folks with lots of Cobra experience that have driven it have told me. The 17" rims allow me to run Wilwood brakes (6 piston front and 4 piston rear) that work really well on the street and track. On the other hand, I went with 15" pin drive wheels on my Unique 427 roadster for a more "period correct" look ... and as you mentioned, there's very little choice for DOT tires in 15". I'm running Firestone Indy 500 radials on the Unique but thinking of switching to the Goodyear "Billboard" tires. I know this is kind of an "apples to oranges" comparison, but my coupe with 17" tires rides nicer than my Unique with 15" tires. The coupe has 5" longer whellbase and that may contribute to the better ride ... both are IRS cars, though the Unique uses Jaguar IRS.

Garry