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sbca96
04-09-2007, 01:26 AM
I have a question about tierods, the early cars up to about '62 used a
long tube and two short identical tie rod ends. The later cars used a
short tube, a short tie rod end, and a loooooong tie rod end. Does
anyone know if there is any benefit of the later long/short tie rod??
The short/short tie rods use readily available ends, the long/short
use one readily available end, and the long one is quite expensive. I
would rather just get a set of early tie rods for my Avanti, but I am
wondering WHY the change was made. I have also read that the center
link my '63 has is the bushing type, the early bearing type is better?

Thanks!

Tom

'63 Avanti, zinc plated drilled & slotted 03 Mustang Cobra 13" front disc/98 GT rear brakes, 03 Cobra 17" wheels, GM alt, 97 Z28 leather seats, soon: 97 Z28 T-56 6-spd, Ported heads w/SST full flow valves, 'R3' 276 cam, Edelbrock AFB Carb, GM HEI distributor, 8.8mm plug wires

StudeRich
04-09-2007, 02:16 AM
Well Tom you could have hit on something that only the engineer responsible for the change knew, may he rest in Peace! :)
But really, look at it this way: take a '62 Lark nothing else important on the suspension, or steering changed on the '63 model except those long forged rods took the place of the hollow tube, seems lots stronger to me. Thing is I don't know of any problem with the old system after a few hundred thousand cars were driven millions of miles with it! So I intend to replace some of my '63 and '64's with the less expensive '62 type and as you know an Avanti is not a lot different than a Lark 8 Convertible, so I would try it myself. But I can't recommend that you do it. Your wife might be looking for me if you crash & burn! [B)]:D

You will get the pro & con on the bearings vs bushing center pivot thing, many people think the Bearings are longer lasting, but it seems that the bushing is a tighter fit with less slop right from the start. Who knows which is better, but I do believe the housings (castings) are different between the two. The parts book is not much help because it shows a different assy. with bearings installed than the one with bushings (of course) but no empty one is listed. [V]

StudeRich
Studebakers Northwest
Ferndale, WA

Mike
04-09-2007, 04:33 AM
If you install the late tie rod assemblies with the "loong end" under the oil pan, and the adjuster at the wheel; there won't be any interference with the pan. Otherwise the bolts in the adjuster sleeve can hit, if it's positioned with bolts to the rear. With adjusters under the pan, you need to watch out for this whenever someone sets toe in/out. Clearance looks good with the car jacked up; but they rub when you drive it.
Perversely, Stude installed the newer tie rods with the adjusters under the pan. Maybe oil leakage from the front main seal was supposed to keep the adjusters from rusting!
Early Avanti's used needle bearings in the center pivot. They are supposed to be better than the bushings. It's possible to use extra bearings in the housing, (four cages).
Stan Gundry explains the bearings and tie rods in his excellent book.
Mike M.

Mike Van Veghten
04-09-2007, 02:56 PM
Funny thing the bushing vs. bearing debate...

For years...since the beginning of the "race" oriented shaft rocker arms...with some "cheaper" variations, the only way you could get "roller" shaft rockers was with...roller bearings!
Now with various composite materials on the market, Crane and Comp Cams has a "high tech" bearing or actually bushing material for their shaft mounted rockers. Even if that shaft only holds one rocker!

After seeing what happens to small things (bearings) that have a pounding force put on them...kinda like the pivot shaft, I like the bushing method better.
Just put it together clean, burr free and keep it lubed.

As far as the tie rods...in most cases a tube will resist a bending force better than a rod... But in this case...50 / 50. either way works fine.

Mike

sbca96
04-09-2007, 05:22 PM
So its basically clearance to the pan then? The Avanti is the same as
a Lark, and the Lark came with the short/short. Did they tend to hit
the pan also? I might have to make a few phone calls for the tube, or
I was also thinking of having some 7075-T6 bar machined with threaded
ends, & use a lock nut against the tapped hole to pinch it. That will
eliminate the clamp all together.

7075-T6 is the same yield as steel and lighter. Though I might have
to heli-coil the threads for longevity.

Tom

DEEPNHOCK
04-09-2007, 07:06 PM
IMOHO, the change to the short rod ends with the long tube was a part number reduction method used by companies like TRW and Moog. Cheaper to stamp/roll/form a longer connector link than to forge a long rod end. They like to use off the shelf stuff, especially for lower run SKU's. But that's just a parts guy guess...

In order to keep the same strength, you'd still have to upsize the aluminum bar and end up larger than mild steel. That would 'probably' put you into the same interference problem you are trying to avoid.
If you were to use some welded seam mild steel tubing, and drill and tap the tubing you could keep the OD within reason. The only major cost should be the LH tap you'd need to match the RH tap.
BTDT...
Let me know what size threads your rod ends are.
I have a LH tap I can send/lend you, if you want to tap the ends.
Jeff[8D]




quote:Originally posted by sbca96

So its basically clearance to the pan then? The Avanti is the same as
a Lark, and the Lark came with the short/short. Did they tend to hit
the pan also? I might have to make a few phone calls for the tube, or
I was also thinking of having some 7075-T6 bar machined with threaded
ends, & use a lock nut against the tapped hole to pinch it. That will
eliminate the clamp all together.

7075-T6 is the same yield as steel and lighter. Though I might have
to heli-coil the threads for longevity.

Tom


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DEEPNHOCK at Gmail.com
Brooklet, Georgia
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sbca96
04-09-2007, 08:28 PM
Thanks for the offer Jeff, I will keep that in mind. I wonder if I
could just use lock nuts with the steel tube, eliminating the clamps
that way? Hmmmm.

Just to clarify, the short/short ends came first, and than they did a
switch to the long/short toward the end of Studebaker production. The
guess you made would certainly be true on why the replacements are so
expensive. Years ago I found that the short end is an easy cross to
a GM truck, so parts like Moog can be obtained. The point of this is
I can take the tierods off my '60 Hawk, OR just get a set off a parts
car, then order some Moog ends. I would rather get away from as many
hard to find expensive parts as I can on this car.

Tom