Winter Upgrades 72 Challenger

[witorque]

Small block 340
It bump steers a bit, weaves under hard braking and handling is a bit lurchy
with the old bars

That sounds more like alignment and weak steering/suspension bushings to me.

Roger keys did a full alignment at his Monkfish performance business, steering box is good, rebuilt by Steer & Gear Ohio.
These front suspensions are only good within a narrow envelope of movement, then undesirable geometry changes set in.
Bushes are good

[Dave-R]

Stock bushes or Poly?

I used all poly. The key is to stop the lower control arm moving back and fore. It has to do that a little with suspension movement because of the design with the strut to the K-frame. But you don't want it moving with braking and cornering.

I found 1" bars on the harsh side even with a 440. I would keep it under 1" but over 0.9". Invest in bigger sway bars (front and rear) and the best shocks you can afford. Adjustable if possible. That is the key.

[MilesnMiles]

Dave, also subscribed to this one. 1" too big for torsion bars, then?
The problem is that few people switch out torsion bars and I suspect when they do they go over the top having not realised just how much the original bars had dropped in efficiency, and I want to avoid that too.
How noticeable was it when you switched bars on your Challenger?

[latil]

Have the rear spring bushes been changed? Anything up front can be exaggerated by the pendulum effect that sideplay in the rear hangers will give on cornering and braking. Polybush all the rear.

[Dave-R]

How noticeable was it when you switched bars on your Challenger?

Well remember my Challenger had Hemi/440 bars anyway because it was the real deal. Going to 1" bars as well as big sway bars and custom leaf springs increased the suspension stiffness by 30% in total all round not including the effect of stiff gas shocks. Removing a lot of weight from the front so it had a 55/45 weight bias helped too.

It cornered incredibly flat for its size. But thank god for the springs in the seats. I used to bounce in the seat all the time on normal city streets.

What was better was when I fitted adjustable shocks. I adjusted them almost as soft as they go and it was much better.

Our mate Drew in the USA though uses the original 383 torsion bars. With no rear sway bar. All he has is good adjustable shocks. His car handles great. Helped a lot by 17 inch wheels and 275 low profile tyres on all four corners.

There is more than one way to skin a cat.

I am fitting expensive Koni shocks to my Corvette to improve the ride quality. I am told this simple swap makes a big difference. We will see.

£560 for the set inc VAT.

Still waiting for them to arrive as they have to come by ship. Should be here in the next week or so though.

[MrNorm]

A lot of modern cars no longer use taper roller bearings in hubs

Yes, but AFAIK they use another mechanism to take the side loads - like a big C-Clip etc, which is not used on an 8 3/4.

Anyway, I agree that a properly set up, with slop taken out, 'stock type' Mopar suspension is actually a very good design. As Dave admirably proved. And Rick Eherenberg....

[MilesnMiles]

Thanks Dave, that helps a lot. Looks like I'll opt for slightly smaller diameter bars. I've already replaced front bushings shox etc, but can't afford £500 on them
When I went from no spring bucket seats (aftermarket) to Mopar sprung seats the car was more comfortable, but I now slide out of them going around corners!

[V8 Sam]

suspension font end rebuild stylee.

worked wonders for mine.

[witorque]

A lot of modern cars no longer use taper roller bearings in hubs

Yes, but AFAIK they use another mechanism to take the side loads - like a big C-Clip etc, which is not used on an 8 3/4.

Anyway, I agree that a properly set up, with slop taken out, 'stock type' Mopar suspension is actually a very good design. As Dave admirably proved. And Rick Eherenberg....

I found this info on green bearings
http://www.doctordiff.com/blog/tech-inf ... -bearings/

I will still examine my axle shafts before making a decision
If somehow the RH shaft is thrusting out under load, the LH side would off load and run loose

[MrNorm]

Yes I respect Cass's (Dr Diff) opinion, he is pretty knowledgeable, I've met him and bought some stuff from him.
I'd stick with exactly what I said though

Everyone has their own opinion on the Green bearings, but anyway it is a fact that they are not taper rollers so their ability to take sideways forces is way inferior to the originals. Will that cause a problem? Probably not. Has it for some? Yes.

e.g. http://board.moparts.org/ubbthreads/sho ... er=7612558

If they really solve a problem for you, go ahead and most likely you will be OK. If you can stick with the originals, I would.