Rear tire size question and 2"/4" flares......

TOPICAL THREAD
I have driven partially cross country, Chicago-W. Nebraska and some Las Vegas area
Driving on the BFG’s. I consider the BFG’s definitely dangerous on the GT 40. Have had them snap getting on on-ramps even taking it easy on the throttle hot or cold days. It was my first impression driving it for the first test drive on! Couldn’t agree with Rick Muck more.
Just installed a lightly used set of Avon’s ... Night and day difference ! Can think of several other brands I would use before the hard and slippery BFG’s !
 
Awesome looking car Gary. Does your car have any rear quarter extensions? Or does the 295 tire fit in the stock fender well? That may be wide enough for me. But I'd have to see an ass end shot of the car to be sure.

And Walter, I'm glad to see you're a "Keeper of the Speed". ;)

No extensions or flares on my CAV GT 40 as it is the Standard MK1 design. I had bigger Mickey Thompson Radials on it that slightly rubbed on the drivers side (big bumps) on the lower rear bottom Quarter. It really had the big tall tire look of the 60s but AVONs are much better tire.
 

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At the time this video was taken my rear track is 71 3/4" (camber @ -1.1) and front track is 69 3/8" (camber @ -1.8). There is no tire rub at these settings.
How are you defining track? Your numbers are really "large".
Track is usually defined as the distance between wheel center-lines.
 
Hi Bob, I went with the outside measurements, sidewall to sidewall, for this RCR example. Since the OP was wondering about widest combinations within a +2 or +4 and what would fit without tire rub.
 
I have a CAV GT40 MKI Std body and I'm running AVONs and love them!

Frt: 225/60R/15
Rear: 295/50R/15

Looks great. This is the kind of info I was looking for. I don't think I'll be needing flares, depending on the manufacturer. Thanks again.
 
I am right in the middle of the same decision on my Tornado Mk-1 body.
Looking at some American Racing VN427 rims (Halibrand style), a Sydney tyre company is offering a Wheel & Tyre package that was to good to pass up.

I had to decide on the Backspace or Offset for the Rims, taking into account what the actual tyre width was to fit under the mudguard to pass ADR in OZ.

Planning on 18" Rims, as you a better tyre choice for the future here in Oz.
15" won't fit due to the Caliper & Rotor sizes, 16" does not give many options.

So after much measuring and soul searching, it looks like 18x8" Fronts with a 5" Backspace and 18x10" Rears with a 6" Backspace.

Running on Nitto NT555 G2 Tyres.
Front 235/40R18 (Actual Size 25.39"/645mm DIA x 9.45"/240mm Wide)
Rear 295/40R18 (Actual Size 27.28"/693mm DIA x 11.85"/301mm Wide).
 
I am right in the middle of the same decision on my Tornado Mk-1 body.
Looking at some American Racing VN427 rims (Halibrand style), a Sydney tyre company is offering a Wheel & Tyre package that was to good to pass up.

I had to decide on the Backspace or Offset for the Rims, taking into account what the actual tyre width was to fit under the mudguard to pass ADR in OZ.

Planning on 18" Rims, as you a better tyre choice for the future here in Oz.
15" won't fit due to the Caliper & Rotor sizes, 16" does not give many options.

So after much measuring and soul searching, it looks like 18x8" Fronts with a 5" Backspace and 18x10" Rears with a 6" Backspace.

Running on Nitto NT555 G2 Tyres.
Front 235/40R18 (Actual Size 25.39"/645mm DIA x 9.45"/240mm Wide)
Rear 295/40R18 (Actual Size 27.28"/693mm DIA x 11.85"/301mm Wide).

can you post a picture? I was thinking something similar but with 17" rims and was wondering how it looked
 
These are the VN427 Wheels I ordered from St George Tyres in Sydney.
Package Deal with Nitto Tyres. Deal is with 18", but when you place your order they could probably do 17" instead. 2 photo's one 17" and the other 18".

I had ordered 18x8 and 18x10, but unfortunately can't get the 18x10 anymore, only 18x9.5".

With the change in Rear Rim I had to re-think tyres and Backspacing.
Nitto Invo - Front 245/40ZR18, Rear 275/40ZR18.

RACING VN427 SHELBY COBRA WHEELS 5X120 CUSTOM OFFSET AND BACK SPACING

Vintage Wheels offers a VERY Similar Package.
427 5 LUG Shelby 17 with Nitto NT555ZR : Vintage Wheels, Mustang, Hot Rod and Muscle Car
 

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I had 295R19 on a 9.5" on the BMW and was going to go to a 275 with the next set off tyres but sold the car prior to doing this. I think the current ///M3 runs a 275 or a 285
 

NickF

Lifetime Supporter
I have a CAV GT40 MKI Std body and I'm running AVONs and love them!

Frt: 225/60R/15
Rear: 295/50R/15

I was running Mickey Thompson Radials prior to the AVONs and had Goodyear Billboards on my last Cobra and neither can compare to these AVONs. They ride and handle outstanding and have great traction also. A lot of the GT40s vintage racing are using AVONs.

Gary, do you have the gulf rear on your CAV?
 
You can get BF Goodrich in the typical GT40 front and rear sizes.....225 and 295. They're fine for the street but not track. If you have a street set of tires/wheels and also a track set then the Goodrichs can be economical rubber for street driving.

For non-DOT tires, Goodyear "Cobra" bia ply tires are nice looking vintage race tires.
Front: 26.5x8.0-15
Rear: 26.5x10.0-15

GOODYEAR® RACING TIRES : Vintage Wheels, Mustang, Hot Rod and Muscle Car
(read the warnings)

You can get them a little cheaper here:
SascoSports Inc is a full-function racecar preparation restoration shop
(Nice people)

Or even cheaper here
goodyear cobra | JEGS
(free shipping)
 

NickF

Lifetime Supporter
I read that the blue streaks suck for street use because there thin a darty. Better for race track. I have GY Billboards on my cobra and that are nice because they have a good tread, but fronts wouldn't fit GT40. I like the Avon but I can get up to a 13" tire on the back of my 40, and Avons come only 10.5
 
I read that the blue streaks suck for street use because there thin a darty. Better for race track. I have GY Billboards on my cobra and that are nice because they have a good tread, but fronts wouldn't fit GT40. I like the Avon but I can get up to a 13" tire on the back of my 40, and Avons come only 10.5

What size flares does your car have??
 
Booty-licious........ ;o) 390 M@H DR on 15x14s Flares are larger than 4" on RCR.... S
 

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NickF

Lifetime Supporter
I have 335 35 17 on now and I believe they are 13.5" tread wide, and another 1.5" section bulge width. I am getting a set of 15" halli rims probably 12" wide and want AVON that will be same width as my current tire.
 
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