Thread: Rear shocks,,

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I currently have Bilstein coilovers in back and driving over these "bumpy" L.A. roads it's not too enjoyable,,,any suggestions{helpful ones} on shocks?
What type are you all using on Your '32's,,I know Mines a solid axle car but I still think it should be a little softer riding.
Thanks

Bilstein are some of the finest shocks made, have you attempted to fine tune what you have with different spring rates, preload settings, etc. Rarely is an out of the box coil-over perfect for every application. Simply changing to another brand isn't the solution.

Mike

Originally Posted by Mike52

Bilstein are some of the finest shocks made, have you attempted to fine tune what you have with different spring rates, preload settings, etc. Rarely is an out of the box coil-over perfect for every application. Simply changing to another brand isn't the solution.

Mike

I agree with Mike 100%. If you have Duane's standard installation you'll have three lower mounting holes, used to adjust rear ride height, the pre-load spanner adjustment on the bottom of the coil-over plus the "stiffness" dial that probably has six to ten detent positions (clicks) for damping rate. You may need to back off on your spanner, softening the spring rate some, and then if the back end drops too much kick it back up using the lower mounts. Then adjust your damping rate to dial it in for the right rebound. Like Mike says, the Bilstein units are top quality, but if you drive into your local rod shop I'm sure they'll be more than happy to remove them and sell you something else.

those big rear tires are going to bounce the car around some

Most who build cars go with too stiff a coil spring and the shock doesn't get to do much of the work it's designed to do. What rate springs are on the back??? Also, many don't use a shock with enough stroke, most street rod shocks are a 3" stroke, which IMO is too short. AFCO has a chart on their website (and on Speedway) to determine the correct amount of travel the coilovers should have based on the installed height. Bilstein is a quality unit, but if the valving on the shock is wrong, the length of stroke too short, or the spring rate too high they will not give a good ride or good handling........

Here's the AFCO chart on length of travel for shocks.

Thanks Guys,,,I'll try and adjust the coil overs and see how that goes,,I chose Bilsteins because I "know"
they are awesome shocks!

I had Alden shocks on an Oze rod car I bought and asked Alden for suggested settings. They said spring rate should be where car settles one inch from full spring length after weight of car is put on springs. I did that and then adjusted the shock setting to the preferred stiffness I liked and car road like a dream.

Along with what Dave said, the spring rate may be too great. There should be a metal tag on the spring with the rate, i would swag it should be about 200lbs? maybe 225?ish should be in the ballpark.
What happens when the spring is too stiff is that the suspension can't work because the tire is reacting (like Jerry brought up)because it is softer that the suspension.
If you know the rear tire weight then to calculate is inches of spring collapse times 2 springs. Like rear wt is 1000 lbs, then each spring carries 500lbs; each spring has to collapse 2" so the spring rate will be 250lbs per inch.

I had the TCI house shocks on my sedan. Recently blew out a lower bushing so I switched to some Bilsteins I had laying around for another project. The difference in ride is unbelievable (better). I think you may be running too stiff a spring or too much tire inflation. I'm on the same third world roads that you are.

How much air pressure are you running in your tires? On my '32, I run 25 lbs in the fronts and 20 lbs in the rears. I found this amount gives the tread a full contact patch with the road. You can use some powdered chalk from a chalk string, mark you tires, and drive over some paper to determine if your tires are making a full contact patch with the road. That way you can figure out how much air pressure to run in your tires. Our deuces are pretty light in the rear, and 30-35 pounds in the rear tires is actually over-inflating them.

Originally Posted by Dave Severson

Most who build cars go with too stiff a coil spring and the shock doesn't get to do much of the work it's designed to do. What rate springs are on the back??? Also, many don't use a shock with enough stroke, most street rod shocks are a 3" stroke, which IMO is too short. AFCO has a chart on their website (and on Speedway) to determine the correct amount of travel the coilovers should have based on the installed height. Bilstein is a quality unit, but if the valving on the shock is wrong, the length of stroke too short, or the spring rate too high they will not give a good ride or good handling........

Spring rate is 225x10"

That's about what everybody runs---except me!!!! I'd be down around 140 to 150 with a 5" or 6" stroke and double adjustable valving.....then you can get a good ride.

Originally Posted by wingman9

I had the TCI house shocks on my sedan. Recently blew out a lower bushing so I switched to some Bilsteins I had laying around for another project. The difference in ride is unbelievable (better). I think you may be running too stiff a spring or too much tire inflation. I'm on the same third world roads that you are.

I think You correct,I have been talking with RCD{race car dynamics} in So. Cal. and I have been trying to tell them that the springs they sold me are too stiff{225 rate}

Originally Posted by Dave Severson

That's about what everybody runs---except me!!!! I'd be down around 140 to 150 with a 5" or 6" stroke and double adjustable valving.....then you can get a good ride.

I'm definetly gonna get some softer springs,,do You think 175 is good coming dowm from My 225's?