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I ran last night and it came off the line hard enough to bounce the rear slicks. I got 3 hops before it settled back down. I tried changing the tire pressure but when I go below around 13 psi it tail wags with these ET Drags. What is the usual cure for this? I'm running leaf springs with Southsides and drag shocks.

I have a situation with the rear end that I've just been living with. The 9 inch slicks just barely won't fit under there so I run the back end up an inch and stiffer on the shocks. Otherwise the rear will come down on the tires. I'm pretty sure this is what is causing the problem but it is just now starting to show up. I think that means I'm coming out of the hole harder now than it ever has in the past.

One option I have is to go back to an 8 inch tire. They will just fit inside the wells with the rear fender lips rolled up. That would let me lower the rear back down and soften up the drag shocks. The big question here is will an 8 inch slick stick good enough for me to run low 12/high 11? The choices look pretty slim for 8 inch slicks anymore.

The other option I have is to go ahead and tub it and narrow the rear axle and get the tires up under the car. I was hoping to hold off on this until I have to switch to a 9 inch rear end. If I eventually run low 11's what size rear tire is needed for that level of fun? Thats just a looking ahead question for the tubbing work. How much does a little tub and narrow job usually cost these days?
 

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Mac,
I think you might be able to fit those 9 inch tires without tubbing with some different wheels with more back spacing to bring the tire in a little. I have seen non-tubbed early Mustangs with 26X10x15 MT Drags and maybe 28 inch tall tires also.A 8 inch slick should be good for mid 11's if you can get the suspension sorted out. My Falcon never liked South Side bars and works much better with Cal Trac clones.
 

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Well, I think you answered your own question. Stiff suspensions tend to do what you explained.

The shocks are definitely worth looking into, though.

As for room under an early mustang... Yes, 28" tires are a pain to fit (I assume your 9" tires are 28&quot
You might have better luck with a set of 26x10's. The small Mickeys (26x8.5) which are 8" wide, are good with 'stock' suspensions down into the high 11's in most cars. Hoosier makes a 26x9 if you are interested... but if I were you, I'd look into a set of 26x10's. I've had them on my car, and they fit easier than 28x9's. My car ran a 1.46 60ft with them.


Get the suspension softened up on the car. You'll only be aggrivated until you do.

Good Luck!
 

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I'm with Greg on this one. I've seen a guy locally that has a 66 Fairlane that lifts the rear tires even on the first gear change! Sounds like the shocks are too short.
 

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I had the same problem with my Mach even though I was running 11.5x30 slicks. It would launch, plant the tires, top the shocks and break loose. I put on stiffer shocks that were 2 inches longer when extended, and it got a lot better but didn't totally cure it. I finally tack welded a small 4"x 1/4" steel plate to the body about 8 or 10" ahead of the spring eyes and lengthened the slapper bars I was using about a foot so that they planted dead center on the plate. I use about 1/2 - 3/4 of a inch of slapper bar snubber to plate clearance. That cured the problem and gave me more front end lift as well. The car hooks far better with that setup. It's almost impossible to make it spin now.
 

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This post has me thinking I am missing the concept all together. I thought the rear tires tried to suck up away from the track. Does the position of the shock mount play into the situation? (Compressing if in front of axle and extending if behind?) Is playing with shock mounts and the effective leverage on the shocks an option?
 
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