My 37 coupe has a complete 69 Camaro rear and suspension. Took both leaf springs out last week and took them to a shop to be rebuilt with new liners and new bushings. I did not have them re-arched. When I initially removed both rear shocks, I noticed that they were extended pretty far. I reinstalled the springs, and found that the only way I can get the shocks to mount over the "pegs" is by fully extending them. They have no downward travel left. The measurement at rest between the upper and lower mounts is 13". My current shock, fully extended is also 13". Fully compressed, it is 8.5". So, I need to go shopping for new shocks. I'm thinking I need at least another 2", maybe 3" of additional fully extended travel, i.e., a shock that would be 15"--16" fully extended. I'm also thinking that with my "at rest" measurement of 13", I should consider a shock with an additional 2"--3" of compression, i.e a shock that would be 10" to 11" fully compressed. Is my logic sound? Is an additional 2" sufficient? Is 3" better? What say you. TIA.
You need to figure out what the smallest or compressed length is when the rear axle hits the bump stops. Then figure out where ride hight is, 13"? Then add about 3" for rear end drop when going over a bump. Then you can figure out how much travel the shock needs. Also check with the extended length, if you can get a rear tire off and out of the wheel well with the car jacked up.
Getting the rear tires off has been an adventure, as the shocks are at their fully extended position. It can be done, but it's a PITA. You're saying adding 3"... in my case a 16" drop would be sufficient. There are no bump stops, so the compressed length will have to be an educated guess.
Are the shocks vertical, or at an angle? pictures are a huge help, when folks are trying to help you figure out something that they can't see, and is not stock. Generally, you want the suspension to bottom out (preferably on rubber stops) before the shocks bottom out. And you want the springs to drop down all the way, with the frame supported by jack stands and the axle hanging free, and the shocks should have a little more travel. You don't want the shocks limiting the extension suspension travel (much). It's usually ok to have the shocks limit the extension of the springs a little bit, but it's best to have enough travel that in normal use, the shocks never hit the end of travel.
That's an interesting suspension setup! I wish I could remember how I did the shocks on my 39 way back when, I think they mounted to one of the original shock mount bolts ahead of the axle, and angled back at the bottom? Putting them at an angle allows you to use longer shocks, and they don't get too short as the car bottoms out. Might want to see what you can figure out? You'll probably want to get some longer shocks, but first do some measuring and figuring where the suspension moves, etc. side note, do the ladder bars vs leaf springs, make it bind before it bottoms out?
Canting them over to 20 degrees stops lateral movement however they need to be longer for relocation at top. Rule of thumb is 1/3 compressed at ride height. Looking at those ladder bars I suspect you wouldn't get an ideal ride?
On my '40 Sedan I added a crossmember across the frame above and just forward of the rear end and angled the shocks to mounts on it. I moved the lower mounts to the front of the U-bolt plate. It looks like the arc of your ladder bars and the suspension arc are way different, does it bind when it goes over a bump?
No binding at all. The rear end moves up/down smoothly. With my old shocks removed, I can easily push the rear end down 4"-5". With the suspension at rest, I can pull it up 3" or so. If I was stronger and younger, I could probably lift it more. If I let the suspension "bounce" and re-settle after pushing it down, there are no binding issues either.
http://www.speedwaymotors.com/Pro-S...-Rod-Shock-13-1-2-Inch-Ride-Height,35661.html This looks like a good choice. I have searched for several days online...
I ordered the shocks in the link above. They are working fine. I have about 3.5" of compression and 4-5" of extension. Thanks for the advice.
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