Moving leaf springs for bigger tires.

Britt

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May 2, 2002
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South Carolina
After reading the "pics of lowered mustangs" thread I looked under the rear of my 66 to see what options I have for getting bigger meats under the car. As of now I have some old 60 serise "Drag Rite" tires that my dad had on magnum 500s for right now untill I get the car on the road. From bulge to bulge the tire is about 10 inches wide. There is about 1/4 - 3/8 in between the tire and the spring, and I dont think i have much more room on the outside where the fender might contact the tire.

I was looking and there seems to be enough room to move the leafs on the inside of the frame rails instead of strattling them like the stock setup. I just dont know a safe and strong way to mount them. And also how would this effect handling?

Is it worth it? I dont want to go with flairs, because I dont like how they look on a street vehicle. I just would like to get some tires 275 or bigger under there without rubbing or sticking out.

Thanks
 
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grego37

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May 12, 2004
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Fresno CA
yes its possible, and a great idea if you want to fit bigger meats.I think there was even a kit avail, I think if you buzz around enough on the internet you'll find out what you need to do.
Keep in mind if/when you do this move, there will no longer be space for you tail pipes to exit out the rear. Normally the tail pipes go on each side of the gas tank and I think if you moved the leaf springs, there wouldn't be room.
you'd have to have the exhaust end near the rear end housing pointing down, or somehow exit in front of the rear wheels.
thats the only reason I didnt do it, I have a 67 shelby clone and I love the way the 3" chrome exhaust tips look comming out of the rear valance.
good luck.
 

RaSMG

Founding Member
Oct 5, 2002
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Central Cali
the competition engineering weld-in subframe connectors have a provision for moving the leafs in 3", iirc. also had to notch out the floor pans, i exchanged em for the 'bolt-in' ones.
 

brianj5600

Active Member
Sep 19, 2003
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Middle TN
My 67 looks like the stock frame rails could be relocated. The area of the floor pan looks the same shape up to the tank, about 2". I considered it, but 67 already has larger wheel well. When I get a turbo on it, I will need all the help I can get with street tires.
 

Britt

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May 2, 2002
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South Carolina
GreGo, Yea I thought about the exaust and Im not to attached to running the pipes out back, so thats not a problem. If I decided to run them out the back, I could put in a fuel cell for more room.

RaSMG, Where can I get the subframe connectors?

Historic, Do you have any info or pictures of this? Do you have any tech or know how they do it?

Also, How does this effect handiling? I cant see it being a problem especially if Cobra Automotive is doing it.

Thanks!
 

Travis77

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Oct 1, 2004
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Baytown, TX
I searched around for quite awhile for a mini tub kit, but could not find one. I had a guy help me with my tub job. We welded chrome moly between the frame rail to make the new spring hangers. This tubing was welded to a plate that was welded to the inside of the frame rail. Next we took some measurements and came up with the diagonal line that would be the notched out area of the frame. Once that was filled in with plate, we fabricated a slid-a-link rear spring hanger. I was pretty proud of it untill I brought the car to a body guy and he kinda laughed. But then of course this is the same guy that quoted me 20k for paint and body, I guess his nick name is Foose or something. Hope this helps somewhat.
 

washMO66

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Oct 30, 2001
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Washington, MO
This is something that I have been considering doing as well so if anyone can point us in the right direction that would be great. A little more tire on the street without sacrificing handling or doing a whole back half / four link would be great.
 

Bullitt

Packin' Heat
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Jan 13, 2000
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i would think this would have at least some effect on handling. for one thing, you're changing the moment arm on the spring, so you're going to have a slightly different wheel rate. course the change should be small since the spring is only moving like 3 inches, but it'll still be there.
 

mdjay

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Dec 9, 2003
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iskwezm said:
I have 17X8"s and 275/40's on my 65 FB and they fit with about 1/2 in left on the inside.Also its lowered 1 1/2 and has also sagged a bit with the truck full of stereo,batteries, and NOS bottles.

The front of the wheel house is the biggest problem with these cars. Not as much the springs.

With a 8" rim and a 4.75 backspace or a 9" rim with a 5-5.5" backspace, you can run a 275 tire on a 65-66. To be safe, you should be running a panhard bar and do a little work on the inner wheel house. The 5.5" backspace would require moving the wheelhouse.

There is a poor boy way to do a mini tub on these cars. You can move the inner wheel house up to 1-1.5" inward with a little massaging. You make a 8" verticle slice in the front part of the inner, right where it turns. Then you use a flat piece of steel and a mallet and go to work. When you're done, you will need to weld in a little pie cut piece of metal to fill it in. A little bead of silocone on the trunk side to fill in the slight buckling. I've done this several times and have had good results. It lines the wheel house up with the leafs.
 

mdjay

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Dec 9, 2003
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washMO66 said:
This is something that I have been considering doing as well so if anyone can point us in the right direction that would be great. A little more tire on the street without sacrificing handling or doing a whole back half / four link would be great.

If you have a couple extra bucks to spend, I've heard good things about these set-ups.
http://www.ridetech.com/productinfo/airbarstang.asp

I would definately go this way ahead of moving the framerails.

http://www.ridetech.com/techarticles/WR0183open.pdf
 

washMO66

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Oct 30, 2001
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mdjay said:
If you have a couple extra bucks to spend, I've heard good things about these set-ups.
http://www.ridetech.com/productinfo/airbarstang.asp

I would definately go this way ahead of moving the framerails.

http://www.ridetech.com/techarticles/WR0183open.pdf

Although you still have the same stock leaf mounting position in front of the rear wheels I would assume the width of the bar would give you another 1" of tire clearance maybe?

Sounds like an impressive set up and looks like it would improve the handling of the car. I just wonder if it can stand up to higher HP applications on slicks?

Does anyone have or know someone first hand that has this set up?

Does it require and / or come with a compressor of some sort?
 

iskwezm

10 Year Member
May 24, 2005
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Rowland Heights,California
mdjay said:
The front of the wheel house is the biggest problem with these cars. Not as much the springs.

With a 8" rim and a 4.75 backspace or a 9" rim with a 5-5.5" backspace, you can run a 275 tire on a 65-66. To be safe, you should be running a panhard bar and do a little work on the inner wheel house. The 5.5" backspace would require moving the wheelhouse.

There is a poor boy way to do a mini tub on these cars. You can move the inner wheel house up to 1-1.5" inward with a little massaging. You make a 8" verticle slice in the front part of the inner, right where it turns. Then you use a flat piece of steel and a mallet and go to work. When you're done, you will need to weld in a little pie cut piece of metal to fill it in. A little bead of silocone on the trunk side to fill in the slight buckling. I've done this several times and have had good results. It lines the wheel house up with the leafs.
I sar your car at Knotts and its pretty clean,but I can say my back end sits about a inch lower,so the outter wheelwell is right over the tire,leafs are old,but id rather bag it then put money in lefs again..I thought the problem was the leafs,not the sheet metal???
 

mdjay

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Dec 9, 2003
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Las Vegas, NV
iskwezm said:
I sar your car at Knotts and its pretty clean,but I can say my back end sits about a inch lower,so the outter wheelwell is right over the tire,leafs are old,but id rather bag it then put money in lefs again..I thought the problem was the leafs,not the sheet metal???


The tire will hit the front of the inside wheel house way ahead of the leaf springs.
 
Britt said:
Historic, Do you have any info or pictures of this? Do you have any tech or know how they do it?

Also, How does this effect handiling? I cant see it being a problem especially if Cobra Automotive is doing it.

Thanks!

Britt, I sure do not have any tech but they do a great job. Was under one of their cars at Sebring a few years back and it took some studying to figure out what was different - they do a great job but the cost must be very high. That car also had a fifth shock which somehow got through tech!

It is done to create more oversteer (make the rear end loose) to negate the horrible understeer (front does not want to turn) in the early models.

I again remind everyone that way to much attention is focused on the front end of the early models.

HistoricMustang
www.historicmustang.com