Wheel Offset Question

I don't think you're going to make it. It might be close. If you already have the wheels and tires you can try but I wouldn't buy them. Is your car lowered or does it still have the spacers mounted on the springs? The tire size is right but I think you wheel is too large and will pull the wheel into the fender lip. I'm pretty sure my 17x8s with a 5-1/2 backspace and a 245/40-17 are the biggest that will fit under a stock body but my car has been lowered. There is barely enough room to run a finger between the tire and wheel. My tires rub on the inside against the frame rail behind the tire at full lock. If there is someone who has made the size work, they'll chime in. You've come to the right place for that.

Yes, the car is lowered and is using Hall (Aldan) shocks. So, there are no spacers. I haven't purchased any wheels yet but I was looking at American Racing Cobra wheels which look like Halibrand knock offs. Unfortunately, they only offer upto a 4.5" offset on their 17 X 8 wheels which I know will not be enough. That is why I was looking to move up to the next size which is a 17 X 9.5 in order to get a better choice of offset.

The fronts on 6018 are 18 x 9, 5.75" backspacing according to my last best measurement (25mm off-set). The tires are 245/35ZR18 Michelin PS2's. The car is lowered and there's no outer-tire rubbing issues. The inner tire rubs at full lock.

cowboy from hell

quote:

fronts on 6018 are 18 x 9, 5.75" backspacing

What do you have on the rears George?

20 x 12 wheels, 325/25ZR20 Michelin PS2's, 6.75" "measured" backspacing (12mm off-set). I'd recommend 19mm off-set to everybody else. 19mm is a necessity with 335mm tires. I like the 325mm tires for the bit of wiggle room they give you.

If you are interested in Halibrand Cobra style wheels you should check out;
http://www.team3wheels.com/ac/
They will custom make whatever off set you like!

I just bought a set of these in 17x8 and 17x11, and I like them a lot. Nice and light, too: fronts 17 pounds each, rears 19.

Compomotive understands Panteras and their offsets, and even asked me if I wanted them "East Coast" or "West Coast" style; apparently the West Coast drivers like them sticking out a bit farther.

Sorry, no pix yet. Last time I took my camera out I forgot the car (or was that vice versa?).

Marcus, which did you go with? East coast or West coast style?

quote:

Originally posted by eclectechie:
...Compomotive understands Panteras and their offsets, and even asked me if I wanted them "East Coast" or "West Coast" style; apparently the West Coast drivers like them sticking out a bit farther...

This depends upon the tires you are installing and which end of the car you are writing about, the wider the tires get, the less room for error there is. There is also less room for error in the rear than the front.

The 325/25ZR20 tires on the back of my car leave ZERO room for error. Altering the centering of the wheel 1/8" in either direction would result in rubbing. The 315/35ZR17 tires that were mounted previously did leave some room for error. The 17" rear wheels previously mounted on my car were centered 1/4" more inboard than the 20" wheels are.

Out front its a different story. You are balancing between rubbing on the fender as you center the wheel further outward with rubbing the inner fender at full lock as you center the wheel further inward. The 17 x 9 wheel previously on my Pantera and the 18 x 9 wheel mounted now both have 5.75" backspacing. It looks like you could center the wheel 1/8" further outward without rubbing the fender, (i.e. 5.625" backspacing on a 9" wide wheel) but I wouldn't go any further. Going the other direction, moving the center of the wheel further inboard will simply mean you won't be able to crank the wheel full lock as far when you are entering or exiting a parking spot. That's about the only time you use full lock anyway. BUT, in the looks department it is possible to move the wheel too far inboard.

HOwever, moving the centerline of the front wheel affects the front suspension geometry, specifically the scrub radius, aka the kingpin offset. Increases in scrub radius make steering effort harder and increases the "feedback" felt through the steering wheel. Decreasing scrub radius has the opposite effect. See the picture below.

Hope that makes sense to y'all.

cowboy from hell

George, your wheels and tires make your car look like a current super car production.
It's amazing how the basic Pantera design still works so well.
Who needs flares? That's so '80s.

quote:

Originally posted by ShotgunGrooms:
Marcus, which did you go with? East coast or West coast style?

Well, physically here in Victoria I'm somewhat west of Los Angeles, but due to my northness I guess I am more philosophically aligned with the East Coast; I went with the East Coast style.

The backspacing values for my wheels, old (original Campys) and new:

Front: 4-1/2" old, 5" new
Rear : 5-1/2" old, 6-1/2" new

So the new wheels stick out 1/2" more than stock at the front, and 2" more at the rear. I have only one clearance issue, but it is specific to my Pantera: the Aeroquip brake lines on the front rub at full lock, and need to be re-routed a bit. (I already did what minor re-routing I could without taking stuff apart.) There is absolutely no interference with the chassis or fenders anywhere on my narrow-body car.

For tires, I am running Michelin Pilot Sport PS2, 235-40-17, 335-35-17. I am really happy with the setup, with one minor quibble: I didn't realize that the sizes I ordered would give a whiff of funny-car flavor to the appearance of the car from some angles, mainly the rear-quarter view. However, the straight-on view from behind more than makes up for it.

I really, really wanted a set of 17" Campy clones in the sizes I ordered, but I was just too uncomfortable with the availability issues. If I smash one of these, I know I can just order a new one, or even get it fixed if only one of the three parts is damaged.

Happily, I think these wheels look fantastic on the car. The color is great, and they aren't all air like the more modern-looking wheels; they have massing quite similar to the Campys.

I'll just have to wash the car tomorrow and take some pix for you all. For now, I think I'll grab a beer, go sit in the garage, and look at it...

quote:

Originally posted by eclectechie:
...physically here in Victoria I'm somewhat west of Los Angeles...

Beacause of the curvature of California's coastline and eastern border, Lake Tahoe is actually further west than Los Angeles!

quote:

...For now, I think I'll grab a beer, go sit in the garage, and look at it...

That's bitchen! Enjoy!

As promised, here's a pic of my car with its new shoes:

And one more, for good measure:

Very nice Marcus. I was thinking of those wheels also.

You can't beat a red Pantera!

quote:

Originally posted by Silver72:
Does anyone know if on the front of a stock bodied Pantera, a 17 X 9.5 wheel with a 5.25" backspacing will fit utilizing P245-40-17 tires or is this wheel size too wide causing the tires to rub on the fenders?

I run that size tire on the front of my 72. My wheel measures 9" inside, bead to bead. It is 1/2" too wide for the tire but it does fit with my 5 1/2" offset. Ask Jerry at PI