Thread: Rear susp questions

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Has anyone built their own rear susp based on the set up under the old chev trucks? The coil spring, long lower arms, I think like 60's up to 72 or so. I was going with a 4 bar, coil over, and panhard bar deal under my 51 Dodge business coupe, but from what I've seen of this set up, it looks like it would work and ride good. Post up some info and pics if you got them, thanks.

Originally Posted by vht

Has anyone built their own rear susp based on the set up under the old chev trucks? The coil spring, long lower arms, I think like 60's up to 72 or so. I was going with a 4 bar, coil over, and panhard bar deal under my 51 Dodge business coupe, but from what I've seen of this set up, it looks like it would work and ride good. Post up some info and pics if you got them, thanks.

It works really well. NASCAR adapted it. Use the longest Panhard bar you can and mount it level with the pavement, from the backing plate vicinity on one side to a frame extension on the other side.

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It works good, but study it carefully before you build.

The original arms are an I-beam design. That's deliberate. The arms are meant to twist during suspension movement. As I understand it, they were made from spring type steel or at least a grade that will take repeated twisting.

The actual truck parts still fairly plentiful. You might do well to find a pair of genuine pieces.

I had a '72 Chevy pickup and went the opposite direction - installed a narrowed 9" Ford rear axle, ladder bars, tubs, fat Mickey's, coil overs and a Panhard bar. Whatever blows your skirt up, I guess.

NASCAR has developed that system over the years and all the crews have a lot of experience with making it work in all conditions. I wonder if that's the main reason they have kept it for so long.

its the nine inch ford center section----------

Funny that they would still use the 9", too. It has a deep hypoid gear set and generates a lot of heat due to the sliding action of the ring and pinion. The cars run coolers that circulate gear oil through the rear. At least the ones I've looked at close up do.

A modern quick change type rear would allow the driveshaft to be just as low, but run cooler due to a just having a spiral bevel gear. I think NASCAR doesn't allow them on cup cars, though.

Sorry, guess this is getting OT of the original post.

Didn't think about the flexing. I've seen some do it, make their own, out of box tubing. All the one's I seen though had air ride. I've searched on 3 sites and have found nothing. I just really enjoy making my own stuff. Save money that way. It looks like to me the bushings in the front would allow for the flex. I'd have to figure out length.

Originally Posted by vht

It looks like to me the bushings in the front would allow for the flex.

Stock type rubber bushings MIGHT allow enough flex. The constant end to end rocking compression would probably shorten their life.

Polyurethane for all intents acts like a solid bushing. Don't count on much flex.

The "Johnny Joints" that the off road guys use would work. They're really just large rebuildable spherical bearings. They should allow all the twist you need.

i still have stock leaf springs under my 50 chevy coup drives and rides better then my new chevy truck i know you did not ask this. but you would have alot of money and work to get aset up in coil over to ride and work better for the cost . the chevy truck 60sto70 set up was piss poor set up good for big time wheel hop . the Aor G body GM have a better 4 link set up or build a 3 bar . i built some set ups. and on lower buck builds i used rect steel tubing boring holes were you want a bushing weld round tubing in holes to fit the bushing O.D caps ends press a bushing in done

Not familiar with jolly joints, but I'll ck that out. I was thinking heim joints in chrome moly, but would make it pick up everything in the road. If this set up is that bad, why would so many people use it along with Nascar? If you would use coil springs and regular shocks you wouldn't have a whole lot invested. Checker racing has a 4 bar set up with coil overs, panhard bar, crossmembers, complete for $575. I got a lot of the steel, I just thought aa person could build a good set up, save some money, and have the satisfaction of doing it.

I meant johnny joints. Hands are stiff this morning.

Originally Posted by vht

Not familiar with jolly joints, but I'll ck that out. I was thinking heim joints in chrome moly, but would make it pick up everything in the road. If this set up is that bad, why would so many people use it along with Nascar? If you would use coil springs and regular shocks you wouldn't have a whole lot invested. Checker racing has a 4 bar set up with coil overs, panhard bar, crossmembers, complete for $575. I got a lot of the steel, I just thought aa person could build a good set up, save some money, and have the satisfaction of doing it.

well then go for it been down this road .you do not need moly steel for links used D.O.M and put alot of power thru it . allstar catalog has many pre made parts that can help .

Here's a link to what I'm talking about. Several companies sell them in various sizes.

Currie Enterprises CE-9112 - Currie 2.0" Johnny Joint Rod End - Quadratec

I agree that moly isn't needed. I've used 4130, but only because I had a source that was cheaper at the time than DOM. Moly takes care to get a good weld. It has enough carbon in it to get brittle if it cools too fast.