Corrected Geometry?

[stu in wichita]

Hotchkiss has a "corrected geometry" tubular upper control arm. They say it's necessary to get the caster right on lowered cars.

Is it worth the cost for a street driven car? Mine will be lowered a little, but nothing extreme.

Is it really that big of a problem with the stock arms? I wonder if it makes a noticeable difference in normal driving.

Do a lot of people use these? I've never heard anyone say that they have them.

Is there any other way to squeeze a little more caster adjustment without going to a tubular arm?

Thanks for the input.

-Stu

 

[moparleo]

Camber is also very limited on e-bodies. When ever you change to ride height on any vehicle, the camber, caster and toe need to be readjusted. To gain more adjustment you have really only two options. Replace the upper control arm bushings with specially made offset bushings made by Moog. This with will give a slight improvement or replace the upper control arms made by several different companies that allow a much greater amount of caster, camber adjustment. And, yes when your car is aligned properly you will notice the extra stability at higher speeds, and improved tire wear. But most importantly you need to find someone in your area who is experienced in aligning older, rear wheel drive vehicles. Most shops nowadays only set the toe, as most cars are front wheel drive and don't allow any other adjustments without adding bushings and plates to make caster or camber adjustments.
The cost of most aftermarket upper control arms are very reasonable and include new bushings and ball joints.

 

[stu in wichita]

Thanks for the info, moparleo. I looked up the offset bushings and they look to be a cost effective solution. I think my old control arms are useable - at least I hope so. New ones start at around $100 each with ball joint and standard bushings, which wouldn't be used.

One question about the Moog bushings: When you press them in, does the offset typically go in a specific direction? By that, I mean, do you position the offset to move the arm away from the body, up, down, or what?

Regarding alignment, you're absolutely right - a tire store with an expensive rack probably can't do a good alignment on these old cars. I'm fortunate to have a real alignment man with lots of experience.

Thanks again for the help.

-Stu

 

[moparleo]

The bushings are marked to install for either max camber or caster. The new arms are pretty cost effective when you consider that replacing the old bushings require removing the old control arms. Having access to a press to install the bushings. If the arms are old, the ball joints may need replacing which will be found out at the time of removal. The bushings alone are about $35.00 each. If you have the money, it is something to think hard about doing. The benefits far
outweigh the price.

 

[stu in wichita]

My son and I totally rebuilt this Challenger about 16 years ago for his first car - it was really used up, but it came out pretty nice. Add another 75,000+ miles, some dings and dents, and never garaged, it's worn out again. This time, it's mine and I intend to rebuild it and wear it out for the third time.

I'm tearing the entire front end down, so everything will be disassembled, cleaned, painted, etc. I've rebuilt a number of classics, and normally replace everything with new OE style parts. I drive my cars and don't like the harshness of poly bushings. The idea of better ride and handling is appealing so the revised geometry might be worthwhile.

Sorry if I'm being thick-headed, but can I get reasonably priced new arms with the offset bushings? If not, they'd have to be replaced anyway. The ball joints can be a pain, but I have the right tools for the job. Maybe the offset bushing isn't such a big deal - in that case, the new arms would be much easier. Here are some real inexpensive ones I found. I don't know anything about the company, though.

http://www.ebay.com/itm/281031240820?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

If I go with the offset bushings, how do you determine whether to go for max camber or max caster? I assume the installation positions are 90 degrees apart, but I wonder what indications of one or the other I should look for.

Thanks for the help. I really appreciate your experience and advice.

-Stu

 

[moparleo]

That looks like a great deal. I would also consider this:
http://www.ebay.com/itm/62-72-MOPAR...Parts_Accessories&vxp=mtr&hash=item41750ffd01
So many choices that we didn't have just a few years ago.
As far as which way to install the offset bushings. Ideally you had the alignment checked right before you dis assembled the front end and know how much each side was needing more adjustment.

 

[Chryco Psycho]

the original adjustment was ok for the Bias ply tires , once radials were introduced there is not enough adjustment available , the offset bushing should get enough , with the offset bushing you want to swing the upper ball joint & control arm to the rear of the car so the offset should push the front of the arm further away from the mount & the rear should do the opposite .
A couple of my friends have the tubular hotchkiss arms & yes the work but they are having issues with the heim joints , personally I feel the one piece non welded factory stamped upper control arm is a better choice for street use overall

 

[bc3j]

I have installed the Moog offset bushings in my 70 Challenger R/T. Once installed like Chryco stated, I have the eccentric bolts installed with the leading bolt max outward and the trailing bolt max inward. The steering is greatly improved and I have not noticed any excessive tire wear. I use the stock upper control arms. I have not put any gauge to this alignment, but since the steering is improved with no bad tire wear, I'm not really concerned with the actual measurements.

 

[Brads70]

I have the Hotchkis a arms . 3 Years now with no issues. I liked the adjustability.

 

[moparleo]

Personal preference and driving style. The stamped new a-arms with offset Moog bushings for normal street driving. Aftermarket A-arms that give a lot more adjustment and are generally stronger, depending on the brand.
So there you go, stock ride height every day driver or Aftermarket A-arms for lowered and/or aggressive driving style.

 

[Mopar Mitch]

The Hotchkis UCA are a very good design, however, IF you ever choose to run in some sanctioned autocross club events, READ THEIR RULE BOOKS and see what is allowed... Some of the aftermarket UCA are NOT legal, based upon their altered mounting points (example E-Bodies), whereas some other designs are legal. In my opinion, and from others I know running them, you would be more than happy with the FF tubular UCA and legal in most club's sanctioned "Rules" events. Be very careful how you choose your items so you don't regret it later.

 

[Chryco Psycho]

I always worry about tubular control arms anyway , welding weakens the metal beside it , at least the factory arms are one piece