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Tighten up that rear end :)

Generally, a 275-60-15 runs pretty close to 9" of tread width. I ran the same size on a 71 340 Cuda with factory front and rear sway bars and with more camber dialed into the front (ran 14's on the front but don't remember exact size) and the whole car lowered just a bit, it handled pretty good with much better than stock shocks all the way around. Also, it didn't have the poly bushings in it. Don't get me wrong, it wasn't a Viper by a long shot but for an old car still riding on original rubber bushings, it wasn't bad at all....and I'm betting on what 5.7 hemi said....28" tall tires are what you are feeling. You might experiment with more air pressure just to see if it makes a difference. If you're not running max psi, take it up there (or close) and see if it makes a difference. If it does, you found your problem. Just don't go all out until you get a feel how max psi is going to act. You don't want to spin it out and crash. You might even increase air pressure a little at a time and see if things change as more pressure will help stiffen the side walls.
 
Tire size is 275/60/15 on a 15x8.5 rim, guess there will be some flex on them.
I already replaced all bushings with Poly bushings and things are solid, just wondering how to give the rear axle a more solid position.
As i can see here, these mods are not really a good suggestion for a street car how i understand.
Think i will just continue on a sway bar first and see how that works out.

I know these cars are not cornering cars, but with some effort and material you can improve things.
yeh- that was more of a tease- the anti sway bars are always a good idea.
 
It is not that someone told me there is a problem and i now have a problem.
I had noticed this on the car before, and when the car was on the lift he just had a look around the car and told me a 4-link system or so is a good upgrade to tighten the rear axle up.
When i told him about my experience he pointed at the rear leafs and explained this to me.

This is my first classic mopar, and have only driven "modern" cars before so i don't know any better then that.
My other hobby is a Nissan 350Z, talking about cornering and stability :)
2 Complete different worlds, but the good ol' Mopar nails the Z in a straight line...just not when cornering :p

I will hunt down a nice sway bar kit for the rear and install that first! :thumbsup:
Anyway some good info from you guys on all these suspension components i never heard off. :D
With the car being build 13 years before me there will be quite some of these things!
 
FWIW A few years back I bought and installed front and rear anti-sway bars from Firm Feel Inc. onto my '68 Coronet with small block engine. The front is 1 1/8" and the rear is 3/4". They weren't inexpensive but well worth the money in my opinion. I also ordered their Soft Bushing Kit for the rear bar in case I wanted to soften it up a bit, but haven't felt the need to use it. These bars made a big difference in how the Coronet handles the curves! Note: don't go too big on the rear bar. This can make the rear kick out on these cars in the corners.
 
After reading through this thread I'm going to opt in for a beefier 6 leaf set-up over the stock 5 leaf for a 318 Charger. So the only thing pushing these cars forward is the the springs at the hangar bracket? Crazy!
 
The suspension part is fine, caused by the Bilstein's and the new leaf springs and bushings.
It just has a little "swing" going hard left to right or vice versa, which as highlighted by the alignment shop is caused by the fact that nothing else but the leaves keep the rear axle in place.
So the side way movement (swing left to right an v.v.) is what i notice i guess, regardless it would be a good upgrade for a more balanced car.

So like a rear sway bar makes a connection between chassis and rear axle, to me adding some rigidity to the rear axle...right?
I don't entirely agree with what the alignment shop is telling you unless your bushings are wasted in the leafs? Mines a 69 Charger with nothing but leafs in the rear, no sway bar, no panhard bar or anything else and it's tight. I do donuts and everything else with no feeling of anything moving and that's with 11" wide tires that never touch. My guess is it's your tires are causing all the movement back there.

I'm not disputing that panhard bars and sway bars aren't great options but it shouldn't do what your saying even with just the springs.
 
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I have not came to the point yet of ordering a rear sway bar.
To me, just my opinion, it is very obvious when looking at how the rear axle is attached on the car by a set of leaf springs, which their anchor points are 4 feet apart there will be movement if a 400+ HP engine is releasing his torque on it.
But as you said, the big cheeks on the tires are a big sponge for sideway swing as well.

I am just a European kid not used to American Muscles :lol:, but i will get there! :usflag:
 
Did they use factory specs for the front end alignment?
I have a 1969 Coronet 440 (318, etc.) that was very squirrely until I figured out how to get the front end aligned.
The factory specs are no good with radial tires.
 
I don't entirely agree with what the alignment shop is telling you unless your bushings are wasted in the leafs? Mines a 69 Charger with nothing but leafs in the rear, no sway bar, no panhard bar or anything else and it's tight. I do donuts and everything else with no feeling of anything moving and that's with 11" wide tires that never touch. My guess is it's your tires are causing all the movement back there.

I'm not disputing that panhard bars and sway bars aren't great options but it shouldn't do what your saying even with just the springs.
agreed. in all the times of the 60's 70's drag race mopars a panhard or saay bar was never an issue. but, as the postman says -to each his zone. while o nth e rear ends- when a narrowed rear end is used and say a 24" outside/outside chassis is used is there a preference as to hos much the rear ends are narrowed flange face to flange face? I'm thinking 40 to 44". I understand this can be a dealers choice, but I'd like to see whats out there. my race cars have always been 24" outside/outside chassis with 2 x 3" tubing. opinions please
 
He guys,

Got my rear sway bar delivered recently and are getting to the point of installing it.
Do i need to install it with the car resting on the wheels?
I got a kit where i need to drill holes in the frames and install a U-bolt inside the frame to mount the brackets for the link rods.
The sway bar bolts on the axle with U-bolts as well.
 
A rear sway bar has been on my to do list for the GTX, just not a priority.
Now that she's a running & driving rascal, things like the rear sway and some braking improvements are next.
I looked on Summit real quick and they have an "in-house" kit that's far and away the most reasonable.
Wonder who makes it for them? Is 7/8" bar diameter sufficient for our cars?
Hey @HD539 - care to explain just what, precisely, you disagree with and why?
 
On my Bee going to Hotchkiss leafs , HD shackle kit and Andy F's leaf hangers transformed the steering way more than I thought it would .Feels way toss able and controlled .Already had 3/4 rear bar and Bilstien shocks.Had SW leafs with poly spring eye and flipped hanger prior.Then I went with 1.12 T bar and wow !Will shame my SRT8 on a twisty now! So I had to upgrade the sway bars on the heavy beast .

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I have come to a conclusion -the'64 330 dodge I have is very straight BUT the floor pan near front to rear is more patch panels that metal,guess I'll take it to a friendly chassis shop and have it back halved.I will get the 8-3/4 rear end narrowed and use the tires and wheels off my dragster for double duty. I had a n eleephant ear mount made and installed it today- not to much bleeding but a lot of F words.
it's not how much- it's how much a month.. sponsorship accepted.
 
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