Im sick of my Model A having horrible wheel hop. I like to drive the car around 70 and the back end just wants to bounce all over. I had the best man in the business cut and on-car balance all for wheels and tires. The front end is perfect. I started working on the rear end and made some nice tube shock mounts, but the thing rides to stiff. The shocks I used are Pete and Jakes short shocks with a 17 degree angle. Im thinking of fabing up some friction shocks. I just want to eliminate the wheel hop. Any ideas would be welcome.... Thank you.
I would try a good double adjustable shock, like a Koni or VariShock so I could dial in the ride I wanted. They aren't cheap, but good parts rarely are. Larry T
Just curious. Have you had someone drive beside you to witness the wheel hop? One side - - two sides - - not visible? May not be what you think.
What kind of tires and air pressures are you running? Rear suspension setup? Coilovers, transverse leaf etc.
From your post it seems that you are having a ride issue not a shock issue. If you have had your tires balanced, this is not a vibration issue. If you interpret the car to be a bounce issue this would mean that your car is oversprung and every time you hit a bump the tires absorb as much shock as they can and then the stiff suspension just dribbles the car like a basket ball. Do a quick check of suspension travel by taking a zip tie wrap and wrapping it around the shock shaft at the intersection of the shaft and the shock body, Take a quick ride and see how much the suspension traveled. It should be in the area of 1" compression, meaning the zip tie is now positioned about 1" higher on the shaft than when you started. If you have shielded shocks you can use a piece of foam pipe insulation but put the pipe insulation on the shock body and the measurement will still give you an idea of the spring travel. If you are only moving about 1/2" way to stiff on springing. You can put all the shocks on it in the world and its still going to be too stiff. State some more specifics about your ride so its not a guessing game and a couple of pictures would help visualize what your possible issues are.
Softer tube shocks and/or look at the rear spring and shackles. Lots of guys with leaf springs are not set up to allow the spring to work properly. Improper shackle geometry or leaves that don't slide across each other are all causes of ride problems. Good luck
Im in the process of pulling the rear spring now... I have a feeling its just over sprung... It does have wheel hop. It has a standard Model A rear spring on top of a 46 banjo.... with a few leaves removed. The rear perches where welded to the axle tubes according to a rear end chart. SO I know that the rear end is set correctly. Ill try the rear springs first before I mess with the shocks to much more.
FWIW every time I've fought wheel hop (the drag race kind) in an O/T car that wasn't buggy sprung.....the answer was softer springs and getting the rear suspension to move when it should. Sometimes that lies in the geometry more than the spring rate. The highway thing and the wheelhop are likely indicating the same thing.....lack of suspension movement. Good luck!
If you have bind in the rear suspension components, it will feel like it is over-sprung. Transverse leaf springs with rigid mounts are almost guaranteed to bind with much travel. Poly bushings, short shackles, split bones, all contribute to the problem. Look at that stuff, also.
Pulled some springs out of the rear and now have some travel... gonna put a few more shims to raise the back of the car up. Im gonna take it for a ride tomorrow morning and see how it rides. Thanks for all your help!
I'm still curious about what tire - type, size, etc. - you're running as well as the tire pressure. A lot of folks look at the tire sidewall and if it says 35 psi maximum load that's what they put in. If you have a large tire in the back, said tire being designed for a heavier car or light truck, overly high pressure will bounce the car around. Fwiw - I run 20# in my 32 roadsters 285/70R-15 BF Goodrich tires - which are the p***enger car version. When I ran the BF Goodrich 31.50 x 15 LT (light truck) tire - both sets of tires just about the same size as per the measuring tape - I ran 12#-16#. Good ride on both sets of tires although the p***enger car tire is the best of the two. Fwiw - the LT tire had 7 plies in the sidewall, 3 plies in the tread. The p***enger car tire has 3 plies in the sidewall and 1 ply in the tread.
Can Friction shocks control wheel hop? No,but hop is mostly from out of round or out of balance ,less a alot of power is being use on take off in witch case you need good tube shocks anyway in rear. Most friction shocks are too small to work on a rear end, just too much lbs. to control,same for front ends that use 40's drum brakes or newer car disk,about the only place they will work is on a lite T-bucket with little disk and fairly small wheels for the sizes sold now. If you look at the big size frictions on old racecars,they worked but needed adjusting all the time.
I took a mess load of Leaves out of the rear... Seems I wasnt paying attention and just added a bunch to get ride height correct instead of worrying about the ride quality. Unfortunatly Ive been super busy and the freeways have been a mess with all the fires but Ill definatly get it out and run it before the trip to Ventura this weekend.
Went for a ride tonight.... Ride is ALOT better!!!! but now I lost my rear control and possibly have to fab up a rear panhard bar. I better hurry.. Leave for primer nats in 2 days
Cool, man... and this thread is exactly why the HAMB rules. You asked a question, got some great advice, made some changes, and they worked! Malcolm
Just dialed in my A sedan it had tire bounce at cruise speed and i tried everything It wound up being too much caster angle. now its at seven degrees and no bounce
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