My T Roadster has been together for quite a few years. Last year on the way to the Frog Follies the front axle actually developed a "bounce" at times. The tires were new in '21 and although not perfectly round but I wouldn't consider the run-out to be excessive and wheel run-out is minimal. I've had the tires balanced by 2 different shops but the problem still exists. I am considering the shocks might not have strong enough valving, or they're just worn out and not able to control bounce, and eventually they go into an oscillation mode, not being able to dampen the action of the spring and the compressibility of the tire. The shocks currently on the car are the chrome short T shocks from Speedway. Best as I recall they were maybe about $30 each, years ago. Speedway does offer other short shocks, some are gas filled, some not gas filled, some are by PRO shocks, and there are also short shocks from Pete & Jakes that look identical to the ones from Speedway. I also came across RideTech shocks https://www.ridetech.com/product/polished-mono-tube-shock-7-9-11-2/ and although they are a bit pricy, and a bit longer than ideal I would use them if they would solve my bouncing problem. The shocks I would need are about 7.5" compressed, 10.5" extended, with about a 9" mounted length. Both ends need to bushings with sleeves for 1/2" bolts, or they could be spherical ball ends, makes no difference to me. I am just looking for the best shock out there for my application that would have enough dampening to stop the bouncing. Thanks, in advance. Lynn
I admit to being impatient sometime, but I called Ridetech this morning and talked to a tech person about my "bouncing axle" problem. His take on the issue made a lot of sense to me. He said that in their opinion and experience that the springs on many light weight hot rods are stiffer than they need be. The compression valving on most shocks is OK to work with the "stiff" spring(s), but too often the rebound valving is inadequate to stop oscillation. I have a fair amount of circle track racing experience and his explanation of what the shocks are allowing made sense to me, so......tightwad me ordered a pair of the shorty, polished unshielded shocks. They're a bit longer than the shocks I have now and I'll only have about 1" to 1 1/4" of compression on the front suspension before they bottom out, but if necessary and as much as I'd hate to do it, I'll just have to rework my upper shock mount which is incorporated into my headlight mount. Lynn
I recently softened up my front suspension and installed some Firestone ribbed bias ply tires. That ended up causing some front tire bounce at about 45 mph. The tires look like they sat on a warehouse rack because they both have a groove that goes straight across the tread. Wheels/tires balanced off the car when tires mounted. Long story short, I changed my toe setting from 1/8” toe in to zero toe and bounce completely gone. Fortunately no darting around either as can happen without toe in. This is likely a bandaid but totally fine with me as this isn’t a daily driver. My chassis is underslung with parallel front leaf springs, friction shocks and tie rod behind axle but just throwing this out there in case it helps you. Just want to add that I messed with tire pressures and friction shock torque and nothing did the trick like the toe setting. My whole chassis and front end started to bounce as one unit with the friction shocks torqued pretty tight.
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