Front end hop

[donsrods]

Right from the beginning my T ran straight down the road and had no problems at any speed. With only about 30 miles on it I drove it clear to Daytona and back on the interstate with zero problems.

However, I have been getting a little hop in the front tires lately. At 60-65 it is ok, but as soon as I push it a little harder I can see the front tires starting to progressively get more hop to them. It starts out very little, but keeps getting worse, and if I really push it it goes into death wobble.

Today I decided to tear into the front end to see what I could find, and I think I found some possible culprits. My chrome hydraulic shocks have almost no resistance. They were an Ebay purchase when I was trying to build the car as cheaply as possible, and since they were in great shape I kept them. But they are evidently blown out. I checked them against the shocks on my '27 and those are very hard to move in and out, the ones on my '23 are super weak. I am ordering new ones Monday.

Secondly, I am going to have my front tires rebalanced. I had a local shop do them, and this time I am taking them to a friend who has this super duper expensive balancer that load tests them too. We had my Son's T tires redone on this machine and it made a world of difference.

So, I think the combo of out of balance bias ply tires and shocks that would not control the hopping are causing the problem. For the first time in my life I actually considered going to radials, but I have used bias plys for so many years with no problems I wasn't ready to throw in the towel yet.

Don

 

[tfeverfred]

I hope it turns out to be just the shocks, Don. There's no doubt the radials will help too, but man, your car sure looks sweet with bias plys.

 

[EX JUNK]

I think that you have nailed the problem correctly Don. Shortly after putting mine on the road, I had a similar problem. Since I have friction shocks, I adjusted them a little tighter and no more wobble. However, I felt that there had to be something to start the wobble in the first place. Once it started, it set up a situation where it only magnified until I had to hit the brakes to control the car.

I had the front tires rebalanced by another shop and the problem did not reappear even when I backed off on the shock adjustment. So go for it.

 

[donsrods]

Thanks guys for the info. I really think this has to be a big part of it. Like I said, the faster I accelerate the more I can see the front tires starting to bounce. Just a tad at first, and I had to really concentrate and ask myself if I was seeing what I thought I was seeing. But it just progresses from there to where they really take off.

I know radials are undoubtedly better, but I just like the look of bias plies on traditional looking cars. I've used them exclusively for about 30 years or more, and never had issues like I have had, or that my Son has had on his T.

Hopefully, we have his all straightened out now (his newly rebuilt transmission came back from TCI yesterday so we should find out next week when we install it and get the car running again) Now if I can get mine fixed we are all set.

Don

 

[Rick]

Was out yesterday for an hour or so(Eat your heart out Fred LMAO)Damn it feels good to be able to hear that sound and have that wind in my face.Best of all NO WHEEL HOP.Having rid myself of those friction shocks is the best thing i could have done.And not to worry Fred Driving the Lincoln WILL NOT PUT ME TO SLEEP.The shocks i have are the Pete and Jakes Don and they are stiff as heck when you try to move them by hand up and down.

 

[donsrods]

I know Rick, I just replaced the ones on the rear of my T because they were too long, and they are very stiff to move. That is what I am shooting for up front. As I was driving back on the interstate from Billetproof I kept watching my front tires, and it dawned on me the shocks were not doing their job of dampening. Pulling them off and checking them confirmed it.

Don

 

[T-Rex]

I am really interested in this thread. I have a shimmy/hop in my right front at 55 mph. Its fine up to 55 and smooths out above that speed. Got new radials on front ( coker exchanged once) been balanced twice by different shops and now I'm gonna put shocks on the front.

 

[EX JUNK]

I have found that an improperly balanced tire will usually show up between 50 to 60 MPH. Anything either below or above will be smooth. It probably has something to do with setting up a harmonic or something like that. There are probably some guys out there that are more educated than I am that can explain it much better.

 

[PowerGlide]

Don I've never had front shocks on my T. Plus I've got the 16" wire wheels with skinny tires and never had a problem with shimmy.

I have to hit a pretty deep pothole just to get the front end to do 'frog dance'. More than likely there is a tire out of balance and caused it to create some bumps in thead.

 

[ACJC]

The signs and symptoms that some of you are displaying with front end shimmy is what mine is doing. At 50 mph, no problem, 52 and up, hang on to your hat. So, this weekend (since it's a long one), a tire balance job. Hopefully my local tire store buddy will let me do the work on not one of his low paid minions. Then I'll tackle setting the caster, and adjust the friction levers.

I do see hydraulic shocks in the near future.

Thanks to all for sharing!

 

[Ma_n_Pa T]

Wheel hop problems, and please don’t get this mixed up with wheel shimmy, I have been fighting the wheel hop since I got the car on the road 1 years ago. Done the balance act 10-12 times different places with the fancy new machines, done the alignment thing so many time we wore the bolts out and it was better but still there, put shocks on it, changed to a different set of tires and rims. I even went as fare as putting a stronger heavier frame in it, it feels better but the hop was still there. All of the above help but did not completely get rid of the wheel hop.

I tore everything down this year to have the front end chromed and thought I would run the rotors down to be checked for balance while waiting for the parts. I found a little engine balance shop we took them to, he set it up on the spindle and set it in the machine, turned it on and it dam near jump off the machine, it took 1oz of weight on each one to bring them nice Speedway products in balance, when he got done they spun full speed with out holding it in place. As we haven’t got things back together yet and haven’t run it down the road, I would strongly suggest you take the rotors off and have them balanced, according to the machinist, he said 1oz in that close to center would be like 4oz out at the OD of the tires, now that’s a bunch!

Save your money and get the balance work done on the rotors.
Jerry

 

[Rick]

Ok one more time you guys and here goesIT'S NOT A G%D DA%@N SHIMMY.The freaking wheels hop up and down side to side.RIGHTside LEFT side RIGHT side LEFT side got it?SHEEESE.I know shimmy from a hop for cri&t sake.Now THATS my 2 cents worth.
Any way i doesn't matter the hyd. shocks smothed out the front like i said a lincoln.

 

[donsrods]

Ok, I think I have found the problem with my car. I took the front tires to the tire shop to have them checked yesterday and while they were in balance, one rim is bent. These are '46 Mercury wheels that I have had a set of for about 20 years, and I previously used two of them on my '27. Evidently, one of the remaining two was bent.

I brought them home and checked the runout with a dial indicator and it was about 70/1000ths out on that wheel. Even when he was spinning it on the tire machine I could see it jumping around. I am picking up a set of four more of these wheels in the next couple of weeks and am going to check all four and pick the best two for this T. I have to repaint them, but that is ok.

My front shocks are also very weak, so I am replacing them with new ones. Over the last couple of months I learned more about death wobble than I ever wanted to know. Here are some things that were wrong with my Son's T, maybe this might help someone else:

1) The wheelbase was longer on one side by 9/16ths of an inch. In our rush to get the car running we screwed up, pure and simple.

2) His caster was way too much. It was about 11 degrees and we took it back to about 6.

3) His toe in was about 3/16 and we made it 1/16 now.

4) His steering box, although brand new, had too much play in it. I adjusted it tighter and also centered it so that "hard spot" in the middle is now there when the car is going straight. It helps hold the front end stationary.

5) He also had a bent rim on the back. It is a brand new out of the box rim, but was bent. We replaced it, now no hopping around in the back.

6) We had his tires balanced on a sophisticated tire machine that did a better job of it.

7) We torqued his friction shocks really tight so they were almost impossible to move by hand.

8) Finally, we took off the heavy GM disc brakes and put on lighter Wilwood discs. We were advised to do this in the beginning and should have listened.

Now the car goes straight as an arrow with no death wobble. Hopefully when I get my new shocks and new wheels my T will be back to normal too. Hope this info helps someone else.

Don

 

[donsrods]

Oh, I see some of you are mentioning a hop at certain speeds. I had a car that did that one time and they tried everything. Finally, they balanced the wheels and brake drums as a complete unit by putting the whole wheel/tire/brake drum assembly up on this little machine that spins everything together. They found that although the tires were in balance the rotors were throwing it off, so they "imbalanced" the tires to compensate for the rotor. That was all it took.

Places that do that kind of work are hard to find nowadays, but sometimes truck repair shops have them, or shops that specialize in alignment and balancing only. If I still have the handling problems I think I will try to find a place to do that. Also I hear some places can shave some rubber off of the tire contact surface to true them up and take off high spots.

We never notice these issues in our big heavy daily drivers, but these hot rods are more sensitive to balance problems, so they show up as things like death wobble and vibrations at certain speeds.

Don

 

[Ma_n_Pa T]

Settle DOWN Rick, you may have shimmy others have had wheel hop, I’m just trying to tell others what I have found in WHEEL HOP. I can tell you one thing for sure, shocks help a lot but will also cover up a problem that should have been fixed in the first place. As Don said floor balance machines work well but you have to return the wheel to the same place evertime you take it off and if you have to dismount the tire for a fix your back to square one with the same problem, fix it right the first time saves money and time.

Jerry

 

[Rick]

Endless bable SHEESE.

 

[B.C.]

Another thought

To much tire pressure on a light car can cause some bounce

 

[donsrods]

Re: Another thought

To much tire pressure on a light car can cause some bounce

Thats a good point. I called Coker and the guy on the phone said 32 lbs. That seems high to me. I alway ran at about 28 on my '27. Tire pressures are VERY important. One time I installed a new engine in a guys Vette and when I was done I inflated the tires to something like 32 lbs all around. I drove the car to my house and it was white knuckle time all the way there, the car was all over the road. I then read the sticker in the door and it said something like 26 front and 24 rear, so I did that and it was a totally different car, handled like a vette should.

I am going to start playing with air pressures on my T also.

Don

 

[Rick]

Re: Another thought

To much tire pressure on a light car can cause some bounce

I agree 100% but the friction shocks were the culprit here.I'd tighten them up and boom rode like a champ.I didnt like the nylocks on there shocks and using baby powder as a lubricant didn't make me jump for joy either unless you live where it don't rain.I'm just not a big fan of cheap friction shocks. Multi disc yes.One of the guys here makes a multi that he sells.Also my build has the daytona wires.My build was also built with brand new stuff not pot luck nothing wrong with pot luck but you have to check old stuff very carefully to make sure it's to speck.i'm done for now my fingers are sore from yelling.LOL sorry for screaming Ma n Pa

 

[Ma_n_Pa T]

Re: Another thought

Not a problem Rick, I should get the frame back from being power coated tomorrow, should have it back on the road this weekend and we will post and let everyone know the results, All my parts are new but new part anymore are not like they use to be.

Jerry