[123pugsy]

I am working on the frame of my 41 Chrysler New Yorker 2 door coupe and I have no clue about coil overs.

I am planning on using a BBC and a 4L80e tranny.
I figure it should weigh in at about 4000lbs.

I'm using an IRS from an 04 Cobra.

A couple of pics below.

Any ideas on what brands are good and how to figure out what size I would need to get?

Thanks,
Pugsy

[blue54]

I have experience with Aldan and Koni. Both are great shock units. The factor there is money. To determine the proper spring you will need the weight on the rear wheels. Your supplier for the coil overs will be able to use that info to determine the proper spring length and rate.

[123pugsy]

Weight on the rear wheels is an issue at this time as the body is an empty shell.



I'd really like to get the upper mounts done and have the shocks on hand for when I make the new lower arms.

[302 Z28]

More than likely whatever springs you choose now will have to be replaced later as they will prove incorrect for the finished car.

Vince

[123pugsy]

Originally Posted by 302 Z28

More than likely whatever springs you choose now will have to be replaced later as they will prove incorrect for the finished car.

Vince

Sounds about right.

Alden has some that are 17" on centers for the shock mounts.
The guy said to set them up at 15-1/2".
I take it most shocks use the same mounting thru bolt.

Is it a 1/2" bolt that is used?


I'd like to get the brackets for the shocks and the new lower arms done now and just bolt something between as its going to be a long while before I have the weight of the car figured out.

[aosborn]

My rule of thumb is to install the longest coil-over package that you reasonably can. That gives you more options on ride height and spring tuning.

You can likely get design drawings for any coil-over you are considering. That will give you the mounting hardware specifications as well.

As to rate, maybe look at the stock Mustang and start there. A lot of new cars weigh more that a vintage car, even with that BBC. There are likely even coil-over conversion packages built to fit that suspension available and that may save you some fab work.

Andy

[123pugsy]

Thanks Andy.

I will have to get drwg of the Alden unit unless someone has one and would like to give me a couple of dimensions.

[cboy]

Originally Posted by 302 Z28

More than likely whatever springs you choose now will have to be replaced later as they will prove incorrect for the finished car.

Yes, and I've had good luck with Speedway being able to return and swap springs, particularly if you email their tech service early on for size recommendations and then keep the emails to reference later on when you need to swap for a different coil rate or height. They've gone well beyond the normal warranty period to replace my coil overs and/or coils...providing there is no damage or wear.

Other suppliers may do this too, I just know Speedway is pretty good about it.

[123pugsy]

You guys in the States have it made with all the suppliers being down there.

I hope I will be able to swap out springs when the time comes, but it will be so long from now I don't dare order them yet.

[123pugsy]

I ordered a set of Alden # 758's with 400# black painted springs.

They charge only $60.00 less for the shocks w/o springs, so I decided to get these to have something to base my final springs from.

The guy told me the 758's are a racing shock.
He said I should get them set up by someone who can weigh all 4 corners and knows what he's doing.

Did I screw up by ordering these?

[406 bug]

400's will be way to heavy. 200# will hold up to 2000lb in rear wt. (12'' spring). mock up you vehicle at ride height; with the suggested ride height of the shock (from manufacture) you can then establish your mounting bracket location. (1/2" hole). most suppliers as mentioned before, will allow you to exchange springs without charge.

[123pugsy]

Originally Posted by 406 bug

400's will be way to heavy. 200# will hold up to 2000lb in rear wt. (12'' spring). mock up you vehicle at ride height; with the suggested ride height of the shock (from manufacture) you can then establish your mounting bracket location. (1/2" hole). most suppliers as mentioned before, will allow you to exchange springs without charge.

Thanks.
I already know the springs will be wrong.
I ordered 400# as the springs that came with the 04 Cobra IRS are 380#.
My car will be at least 3-500# more than the Cobra, so I figured that was a good place to start.