Thread: 23 T front suspension wobble/shake

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Yes, I do track with you on the terms. At first I was not sure if there were other nicknames for the basic steering parts on street rods vs. street cars.

I assembled a tube front A arm chassis on my 69 Vette with fiberglass mono spring, and had to go through all of this in great detail then to get it laser perfect.


If you look in the photo, you can see the caster is nearly stright up.

Oh, look close at the tie rod links. Notice how there is NO thread showing. The toe is currently maxed in at this time due to no more adjustment opportunity in the shaft.

The plot thickens!

Looks like someone has made an effort to deal with shimmey before! That steering damper that's clamped on to the axle and tie rod is often used to compensate for bumpsteer characteristics, or worn steering components.

As for caster, a handy little tool you should have is an angle finder (protractor), see attached picture. $10.00 at Sears, a quick way to check spindle inclination, also good for checking driveline inclination.

Looks like you've got '49-54 Chev front spindles, and perhaps brakes.

The friction shocks should mount to the front of the frame at the ends of that front, suicide crossmember. The arms would reach forward to attach to tabs welded to the top of the axle. If you go to the Total performance site and look very closely at what they've done you can make it out.

I have the same set up on my 27 T except I'm using a vega cross-steer. I wanted to point out that my steering dampener ( that thing that looks like a screen door regulator) is mounted on the drag link and connects to the lower bar on my radious rods on the passenger side. The idea is to connect the drag link to the axle. Unfortunatly, you can't do that because of the drag link set up you have. I don't think mounting the dampener to the tie-rod and axle helps prevent the kick-back you feel at the steering wheel. Also.. a big priority should be installing shocks on the front. I'm using the friction shocks mentioned before. They're mounted at the front corners of the frame(under the headlites) and bolted to the top bolts of my 4-bar radious rods. You might not be able to connect them there because of the type of "bat-wings" you have, so you'll probable have to weld brackets on the axle. Also...You definitly need more positive caster! You'll have to loosen the adj. nuts on the radious rods, remove the bolts, and either shorten the top rods or lenghten the bottom ones to tilt the axle back. Then you get into the routine of "trial and error". I would take it back at least 5 degrees and test drive the car. Repeat the proccess till it starts to feel right. Hot Rods, being what they are, are all different and there's no universal formula for setting up the handling...just starting points. Good luck.

Thanks for the great suggestions and input.

I think I am moving to the right track here.

I would not weld this stuff. I am lucky to make welds that hold on my future kids pedal car!

Speaking of plating, I am considering grinding all the chrome off and going for powdercoating instead. Still undecided about that. However, if I do that, then there won't be any clash between the brass radiator and lights vs. the rest of the car in chrome...if you know what I mean.

Richard has brought up a good point. The solution to hydrogen embrittlement is to have the part baked to drive off the gas. A quality plating shop would be tuned into this. Since you're probably unaware of who did the plating, that would be another reason to take it to a good plater for de-chroming. They may have the ability to determine if you have that problem. It comes on like fatigue, over time/use. If there's any doubt, particularly if accurate history is uncertain, this may be one of those situations where getting a new axle, with the tabs already welded on, will be both cost effective, and more prudent (from a safety standpoint).

Originally posted by techinspector1
69, I went back and read the first part of this thread where you said the front drums had to go in favor of disc brakes. Discs will require more pedal effort unless you go to power assist and then you're just adding more un-needed complexity to the car. If this were my car, I'd clean up and re-furbish the drum brakes and keep 'em. These brakes were designed to provide 60-70% of the stopping power on a car that weighed somewhere around 3,000 lbs, so they are more than up to the task of stopping your T. I don't see the point in spending money when you don't need to. Besides, the drums look waaayyy more nostalgic. Just my 2 cents worth.

Richard,

I like your suggestion...because that means saving money. I am allllll about saving money.

Right now they lock up really easy, and usually the left one first. My guess is the left one has a little leak. My mom has a dirt driveway, and it just plows the very split second you breath on the brake pedal...mostly on the left.

Thank you! The pictures are great. I really like this one:



As it appears to be a more bolt on unit.

It has been a long time since I dealt with front drums. My 69 Camaro and our 68 Land Cruiser had those.

I assume I will need to hit Napa for new wheel cylinders. The only bad part about this hot rod stuff is trying to figure out what the street car application is for the parts.

I am installing a pertronix on it this weekend and a few other small things as my buddy is giving me these parts. My nephew's 3.5 liter Dodge has a bad water pump and timing belt. I am deep in helping him with that and it is blocking my entire garage right now. It seems like just about when I get cleared up for some smooth sailing...something always breaks!

Richard, I haven't seen anyone use a proportioning valve to the front, but in theory it seems plausible.

69, before trying some creative idea I'd go through the existing system first and bring it up to snuff. You originally mentioned that the car sat for some time. My guess would be that you're having problems as a result of corrosion. Brake fluid is hygroscopic (attracts and retains water), so the wheel cylinders could very easily be hanging up not allowing any modulation. Also the shoe/pivots/springs/drums could all be corroded and causing bind. Doing a system flush goes without saying (although I just did didn't I?) As for parts, I gave you my guess earlier.

Hey guys,

I was out of town this weekend, and a friend invited me to a once a month cruise in at a place called Dade City.

I saw four T buckets there, and all of them had shocks. None of them had the same body, or other features as ours. Most of them were longer in the body and frame with the steering columns tilted way back giving more immediate leg room.

Anyway, I got some good photos of those too.

Total Performance has been great. I just got the first package of stuff I ordered from them today.

Like the T. Could do without the brass. Great suggestions for the brake fix. Very true about the weight problem. Without spending time and money you will probably have to live with the front end lock ups. Rebuild the system first and that might fix the problem. If not try getting a larger bore wheel cylinder. This will effectively reduce the pressure applied to the shoes and reduce the braking force. This is an old Baja bug trick to compensate for tire differences. The larger(19MM) rear cylinders went in front and the smaller(17MM) went to the rear. It supplied more rear braking for the dirt and less front end digging. Yes it seems backwards but it is the way pressures work. It might be hard to find cylinders that will work, VWs use the same bolt front and rear. If you go to discs try ECI at www.ecihotrodbrakes.com Nice parts and lets you use junkyard parts if you want. Good luck and keep posting.

Thanks T2B,

I guess I need to post an update.

I installed a weld on shock mount kit. It is from Total Performance.

In fact, I JUST welded the mounts on this week and as of yesterday finished painting the frame.

It is hanging from the ceiling and engine hoist as I write this.

If all goes well I will have the suspension sitting on four wheels this afternoon.

On the front brakes, I am a bit torn. I would LOVE to blow the $$ and slap on disc...but, $$ is in short supply.

I can certainly rebuild the whole front assembly with new parts...but then I am spending $$ that could go towards the disc.

So, I left the drums alone for now. I will revisit that when I am just about ready to make the car roll.

I am putting new wheel cylinders in the rear as they were leaking.

I will check out that other link and see what kind of deal I can find on a OEM/used disc conversion.

Bob; That's a real good link there ,I like it nice cars.

Vegas

Thanks to you guys and Brian at Total Performance...here is the finished product on the front shocks.

Hard to be sure from the pictures, but here are a few thoughts.

Looks like you are running circa 1954 chevy spindles and brakes. You are also using the stock chevy lower steering arms that connect to the tie rod. That could be one of your problems. The stock chevy arms are designed to go facing the rear of the car, and someone has turned them around backwards in typical t bucket fashion. Problem is, this has screwed up your ackerman ( long story, don't ask) All you need to know is that companies like Total Performance have developed special arms to replace these stock chevy items to get the ackerman back. They move the pivot point out further and restore semi-correct ackerman.

Another problem may be the amount of caster dialed into the front end. Chevies of this era like more caster than Fords, I think like 7-9 degrees, but it has been awhile, so I sort of forget. Your front end looks a little neutral in this regard, at least in the pictures.

Third, your tires may be the contributing to the shakes. I had a set on the front of my '27 that started to exhibit some shaking that would only stop when I hit the brakes hard. I bought a new set of tires and it left.

Lastly, someone has bolted a damper onto the axle and tie rod to probably try to fix the problem, so it probably is an inherent design flaw causing your shakes. I think you should find a good alignment shop who knows more than aligning Yugos, and let them put it on a rack for a 4 wheel alignment. An ill handling car is not only a pain, it is really dangerous. (especially with no roof over your head)