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I could use some opinions on correcting some tire rub on my '67 Mustang.

After some research, I found most went with a 17"X8" wheel on the rear of a '67 with 4.5" backspacing. I searched around and purchased a set of four Billett Specialties 17"x8" rims for my 1967 Coupe with 4.5" backspacing. I mounted up a set of BFG Sport Comp 2's in the size 245 45r17. I drove around by myself for a couple of weeks but noticed no issues (fairly smooth roads to work and back). As the weeks passed, I hit bigger bumps and found the back passenger tire would catch the fender lip. Then I had my wife ride with me and it was really bad. As you can imagine, that did not go over well that she gets in and the tires start rubbing so needless to say, I need to fix it.

My leaf springs are a new 4.5 Grab-A-Trak mid-eye style with Bilstein shocks (also new). I switched to a slightly extended Scott Drake rear shackle (1" longer) thinking it would help and it did a little but not much. I took about 1/8" off the fender lip on the passenger side and it improved it some but if my wife or son ride with me, it is going to rub and sound horrible. It is hitting on the shoulder of the tire and has gouged it slightly already. It seems to catch where the red circle is in the picture below.

738651


The gap at the top center of the tire is 1 1/2" on the driver side but 1 1/4" on the passenger. I see nothing wrong with the springs. The axle is setting on them perfectly so I assume there is just that much variance from the factory? Even if I were to center it better, I don't know that if centered the net 1/8" movement would fix it.

I'm at a loss on what to do. I see my options as follows but am definitely open to any other solution.
1) I can grind on the inner fender lip but there is certainly a limit to the gains that can be made without removing too much material
2) I can buy new rims but this style of wheel is not available with greater offset so I must buy a new set of 4 wheels
3) Have someone shorten both sides of the rear axle by 1/4" and replace the axles (probably still cheaper than these wheels)
4) Get new stock height springs at the risk of an unsightly gap between the body and the top of the tires in the back.

Not the best picture but this is the car at the current ride height.
738652
 

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1st of all, your car looks beautiful and I love the ride height. Have you looked into rolling the fender lips? It will gain some clearance, doesn’t require removing any actual steel, and eliminate the sharp lip that is gouging your tire...


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What's the rear suspension history? Weak, sagging?
 

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Discussion Starter #4
The rear suspension was originally stock, worn, and weak. The Grab-A-Trak 4.5 mid-eye springs have less than 2,500 miles. The Bilstein shocks have less than 1,500 miles on them. The front bushings are new rubber. The rear shackles are new Scott Drake versions which are also rubber. The axle is the stock 8" axle which has not had any external modifications. Am I forgetting anything?

Since the metal in the back is double layer (outer quarter panel and inner fenderwell), I've not considered rolling them. I've no experience with it yet and did not know if it would work.
 

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Youre really pushing max @245 wide, IMO. maybe drop down a size with some el cheapos in the meantime before you ruin those.

Thats a lot of clear space that is closing up. If you don't mind getting new springs I'd get the same drop # just a better quality. Do you know what rate those are? Im thinking those GAT springs must not have a very high rate.

Last ditch--You might try a slight roll between the tire and only where you think it rubs. Have someone put their weight against the outside panel and gently beat it up with a small sledge or use a bat, get a heavy friend to bounce it and try to only tweak that inner lip upwards. Too much flex in the panel and your paint will crack though.
 

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Discussion Starter #7
The Grab-A-Trak springs are 4 1/2 leaf which Mustang's Plus states are a little stiffer than the stock GT springs.

So far, I like trying just a slight roll in the spot where the tire makes contact.
 

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Make sure the axle is centered side to side as well. Might consider swapping springs side to side to see if sag transfers to driver side.

If a spring company is somewhere nearby, take them the springs for checking / increasing the spring rate.

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It might be worth picking up a panhard bar. Those leafs will move side to side under load, the panhard bar will keep that movement to a minimum. You can use it to help center things too since you're off centered by 1/4", although it should be adjusted slightly to one side to account for the arc of the bar. With wide tires, I think the bar is probably a necessity if you're lowered, in addition to the wider tires. The bar is cheaper than new wheels or narrowing the diff.
 

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I did no. 3) and have never regretted it. To me it's a do it once do it right solution. I run 10" wide Micky Thompson S/R tires and reverse eye springs on my '65. No rubbing, no matter how loaded the car is.
 

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I can remember when I put my 225 50 16s on my new 16x8s I drove around the block and came right back to the tire place in San Jose, they took one look at the tires and one mexican kid went in the back and came out with a baseball bat. I freaked as they all said, no amigo - un momento por-favor. The rolled that bat between the tire and the rim both sides and problem solved. No paint issues or anything except when I was on a track or autocross really pushing it in a corner with a compression, then it would hit again. A Watts link fixed that problem forever. Let it roll brother...
 

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Forgot to mention I also have 4 1/2 leaf mid-eye springs, oem type shackles, panhard bar, and QA1 shocks


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Sorry to say, but this is another case of "just because it fits that doesn't mean it will work". If you run with stock suspension then change the tire/wheel geometry, you have to change the suspension to fit (or the body to clear). If you retain the wheels/tires, you'll have to modify the suspension. If you retain the suspension, you'll have to modify the tires/wheels. Your choice.
 

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67 Texas, the baseball bat, a wood one, in skilled hands can do the trick. I wouldn't even contemplate narrowing the axle, thats a VERY expensive way to gain a quarter inch. The problem is the wheel offset is wrong. Any chance in inside of the wheels can be remachined to get you 4.75 backspace ? LSG
 

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Discussion Starter #17
I can't imagine anything being done to the wheel. It is a one piece hoop. The center piece is welded all the way around. I've emailed them about custom sizing but have not received a response. They do not offer a 4.75 backspace in a non-custom size.

I've been busy away from the house all day today but hope to try the baseball bat idea tomorrow.
 

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I have same issue slight dips in road abs so forth. I have not attempted anyone in rear. When I ordered this tyre package back in 2014 from mustangs unlimited mounted ready to go I didn’t know about offset back spacing. I am running a 225/60/15 7 inch American racing TDD. Having all kinds of scraping it’s fileting the side wall of my rear tyres. It’s a bitch I have been heating and try rolling fender It hurts my hand too much. Double metal on rear fender I’m not that wide. I posted some pics of inside wheel casting if anyone can make out the number. What it means. I was at Shelby American the other day they tell me they have a machine shop that machines hub Of wheel. Due to the 8 inch TDD they install on there NOS prototype production cars. I’m gonna have someone else roll the fenders for me. I am running set up like you. New bilsteins. I might have worn on leafs. So I have new one coming this week. Grab a Trak mid eye 4.5.
Moët see how this plays out If I get a machine to shave down pad 1inch. It will be perfect I could even runa wider tyre
 

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I have same issue slight dips in road abs so forth. I have not attempted anyone in rear. When I ordered this tyre package back in 2014 from mustangs unlimited mounted ready to go I didn’t know about offset back spacing. I am running a 225/60/15 7 inch American racing TDD. Having all kinds of scraping it’s fileting the side wall of my rear tyres. It’s a bitch I have been heating and try rolling fender It hurts my hand too much. Double metal on rear fender I’m not that wide. I posted some pics of inside wheel casting if anyone can make out the number. What it means. I was at Shelby American the other day they tell me they have a machine shop that machines hub Of wheel. Due to the 8 inch TDD they install on there NOS prototype production cars. I’m gonna have someone else roll the fenders for me. I am running set up like you. New bilsteins. I might have worn on leafs. So I have new one coming this week. Grab a Trak mid eye 4.5.
Moët see how this plays out If I get a machine to shave down pad 1inch. It will be perfect I could even runa wider tyre
15x7 needs 4.25 backspace. your wheel probably has 3.75. Do NOT have the hub of the wheel machined down it will make the hub to thin.
 
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