More Shock Therapy
Q. I just finished reworking my shock mounts and replacing the dead shocks on my 1946 Chevy hot rod. I had noticed that there was very little of the shaft showing above the cylinder and thought that I needed more shock travel. As it turned out the shocks were shot, maybe due to bottoming out. While I was doing this, a friend pointed out the hot rod on the cover of the Goodguys magazine, which clearly showed less than an inch of shock travel as it drove. This may have even been the yellow sedan they own, which I assume was built by professionals. Since then I have paid close attention to other hot rods in magazines, including yours and have seen this over and over. Am I just missing something? Are these special shocks that don't move much or is this “just the way it is” if you run a dropped axle?
I have seen plenty of shocks mounted with what looks to be a few inches of shaft showing as well, plus lots of the covered type that show no length. I extended mine for 3-1/2 inches of travel at ride height but have not been on the road much as of yet but feel that this has to help, especially as I have new shocks that work.
I wondered if it might be good to point out in the next article to allow room for the shocks to work. Thanks for your time, I've been a subscriber for years and even had my cartoons published in STREET RODDER back in the 1980s.
Noel Cummins, Via the Internet
A. Sorry to say your observations are correct, we see street rods with inadequate shock/coilover travel all the time. We've ridden in cars that had it not been for the tires being drastically under-inflated there'd be no suspension at all. And no, there are no special shocks that don't move much, but there are shocks that aren't right for the application.
From your description you've installed the shocks on your Chevy correctly. Although you didn't say how much travel the shocks have, or their operating angle; 3-1/2 inches of compression travel should be about right, with 2 inches of extension travel. In most street rod applications 3 to 4 inches of compression and 2 to 3 inches of extension from ride height provides adequate suspension travel.
Keep in mind the angle of the shock absorber has an impact on how far it travels in relationship to suspension movement. These numbers are approximate, but close: 3 inches of suspension travel will move a shock mounted at a 10-degree angle 2.88 inches, at 15 degrees 2.79 inches, and at 20 degrees 2.64 inches. For an easy-to-use shock/coilover calculator go to RideTech's website: ridetech.com.
One simple way to check shock travel is to wrap a plastic wire tie around the shaft where it comes out of the body. As the suspension compresses the wire tie will be moved up the shaft indicating how far the shock compresses during normal operation.