Shorter outer Tie Rod ends?

[Ralph]

I'm tearing in to the front suspension on my 40 plymouth coupe. It's a 79 Camaro clip, and it's a bit wide for this car. I got a local race car fabricator to narrow the stock A arms one inch per side. he did a nice job.

Now I need 1 inch shorter outer tie rods. I guess I could cut and re-thread the stock ones, but I'd rather find a stock application that would work. A 90's AWD Astro van is close, but the top of the taper is slightly larger, by about .045 I think. Is that close enough, or has anybody got a better suggestion? I'd like to use a factory part, so when it poops out in Poughkeepsie I don't have to fabricate anything. Your thoughts?
Ralph

[enjenjo]

If the taper is the same, just a bit larger, and you can get the cotter pin in ok, it should be all right to use it.

[Bob Paulin]

If the taper is the same, just a bit larger, and you can get the cotter pin in ok, it should be all right to use it.

The '78-'81 Camaro front suspension is very popular in oval-track racing since it works so well. The geometry is excellent right from the factory, and requires very little to make it work well on the oval-track and in road-racing.

If it were me, I would be trying VERY hard to get things back as close to original as possible.

If the subframe had been sectioned, I would look at shortening up the center link, but since it is the control arms that have been shortened, I think you're taking the right route by shortening up the tie rods.

Without applying the bump steer guage I would, I suspect, want to ream the steering arm taper out a bit to place the ball of the Astro tie rod end back near the same height as the OEM in order to keep it in the same relationship to the outer suspension pivots and cause the least effect on bump steer. (Moving inner/outer steering/suspension pivot points up or down as little as .030" can have a measureable effect on bump steer.)

You have also changed your spring motion ratio - the leverage of the wheel against the coil spring. Depending upon where the cuts were made on the lower arms,  a lighter/heavier spring might or might not be required to get the car to ride/drive the same as before.

If they were cut between the inner pivots and the coil pocket, you've increased the motion ratio, and might need a heavier spring. (roughly ten percent - depending upon how close the original spring was.)

If they were cut between the coil pocket and the ball joint, you've reduced your motion ratio, and might need a softer spring. (Roughly five percent - again, depending upon how close the original spring was.)

If you have also shortened the upper control arms - which would only make sense - this will contribute to a different camber curve due to the sharper arc that will be produced.

If the upper and lower arms were the same length, there would be no problem, but shortening both by an inch changes the upper/lower arm ratio.........just slightly, but changed nonetheless.

You're initial caster/camber settings *might* need to be tweaked to reduce tire wear, and to utilize the new camber curve correctly.

I know it's too late now, but I would have run the suspension through the old camber curve before shortening things up in order to have a base point from which to work. (e.g. OLD camber curve might have gained one-half degree per inch of travel while NEW camber curve might change three-quarters of a degree per inch....numbers plucked from thin air for illustrative purposes.)

Please understand, I am NOT criticizing what you have done. I might even consider doing the same thing myself. As a matter of fact, I've actually cut and spliced these same control arms in the past in order to *increase* the track width on an oval-track car......

.....but, I just wanted to suggest some areas you might want to pay attention to.

I just think it would be a shame to change a couple of simple things and end up with a car that doesn't handle as quite as well as it initially did.

Maybe the combined changes in suspension/steering geometry won't amount to much but, then again, maybe they will! Just be aware of these things if the car feels "different" once you are finished.

I know I'm being a bit anal about it all, but in the arena in which I normally work, the person who gets it "dead-on" has the advantage, and I am used to looking at all the variables, and getting things as close to right as possible.

B.P.

[Ralph]

Bob - Thanks. I really appreciate your input. Regarding the tie rods, I'm still looking to find an exact match taper on a 1" shorter rod. Failing that, I guess I could shorten and rethread the stock ones. Would have already if I had the right thread die.

The A arms were cut between the coil pocket and the ball joint.I don't think a little extra stiffness will hurt, but it's good to know the consequences of cutting the arms. The camber curve issue has me mildly concerned, but there's no going back now.

Very clear explanations, by the way. I understood everything on the first read through.
Thanks again!
Ralph

[1FATGMC]

If the subframe had been sectioned, I would look at shortening up the center link, but since it is the control arms that have been shortened, I think you're taking the right route by shortening up the tie rods.

Bob not to steal this thread or anything, but now that you brought up the subject of sectioning the subframe I have a question.

I recently made a trailer out of a 73 chevy 1/2 ton pickup I had.  I cut the front frame off and kept it.  I have this '51 Desoto limo (4400 lbs. at least ) that I want to put a different frontend under.  Now this car will not see "heavy cornering".  I just want it to ride pretty good and stop.  The pickup seemed to have good brakes, so that is a plus.  It is manual steering, so that will have to be changed to power.  The track width is too wide, but it looks like 3 inches narrower with the right wheels would take care of that.  I've considered sectioning the crossmember and using this frontend.  If so what do you think?  I have it and not much money for anything else.  Like I said this will just be a car to go down the interstate in.

I do also have an '84 Caprice wagon that I'll strip for some parts, and that frontend would also be available, but it is also too wide as is.

Thanks and c ya, Sum

[Bob Paulin]

I recently made a trailer out of a 73 chevy 1/2 ton pickup I had.  I cut the front frame off and kept it.  I have this '51 Desoto limo (4400 lbs. at least ) that I want to put a different frontend under.  Now this car will not see "heavy cornering".  I just want it to ride pretty good and stop.  The pickup seemed to have good brakes, so that is a plus.  It is manual steering, so that will have to be changed to power.  The track width is too wide, but it looks like 3 inches narrower with the right wheels would take care of that.  I've considered sectioning the crossmember and using this frontend.  If so what do you think?  I have it and not much money for anything else.  Like I said this will just be a car to go down the interstate in.

I do also have an '84 Caprice wagon that I'll strip for some parts, and that frontend would also be available, but it is also too wide as is.

A limo, eh?

We've got a local guy with a stretched Model "A" that he built for the sole purpose of being able to take his family - especially the grandkids - to various cruises. It's a neat car.

I, too, have often stated that my pockets contain more lint than glint, and I truly enjoy making something from nothing....

I guess it's really your choice - with the proper caveats, of course.....

Either front-end would, apparently, need to be sectioned, so you need to decide exactly which one you want under your DeLightful DeSoto....

My M.O. would be to take the stock center link(s), and spend an afternoon at my local auto parts store - or auto recycling emporium - trying to find one that is as close as possible in geometry - but around three-inches shorter.....then section the crossmember to whatever difference exists between OEM and replacement center links. That should go a long way towards maintaining OEM steering geometry.

Although I have done it successfully in the past on some oval-track cars, I REALLY do NOT like to cut, weld, and sleeve steering components......but if it is your only option........................

My personal opinion is that  the p/u crossmember just might be the better option from a roll center standpoint......plus, it is almost like a M-II bolt-in, in that it is fully self-contained whereas the Caprice would, likely, be a clip.

The p/u suspension geometry SHOULD have a higher roll center, which SHOULD work better with the higher CoG of the early car, resulting in a car that doesn't lean quite as much in the turns.

Also, alignment specs for Chevy/GMC pickups are listed at various ride heights, so finding a good alignment that tracks straight and doesn't wear tires might be a skosch easier.

Were you just a bit closer to Maine, I would probably swing by your shop one evening and try to talk you out of the Caprice front spindles/rotors  - or the entire chassis - to place in my "inventory" for use on a future racing project.


B.P.

[tomslik]

I recently made a trailer out of a 73 chevy 1/2 ton pickup I had.  I cut the front frame off and kept it.  I have this '51 Desoto limo (4400 lbs. at least ) that I want to put a different frontend under.  Now this car will not see "heavy cornering".  I just want it to ride pretty good and stop.  The pickup seemed to have good brakes, so that is a plus.  It is manual steering, so that will have to be changed to power.  The track width is too wide, but it looks like 3 inches narrower with the right wheels would take care of that.  I've considered sectioning the crossmember and using this frontend.  If so what do you think?  I have it and not much money for anything else.  Like I said this will just be a car to go down the interstate in.

I do also have an '84 Caprice wagon that I'll strip for some parts, and that frontend would also be available, but it is also too wide as is.

A limo, eh?

We've got a local guy with a stretched Model "A" that he built for the sole purpose of being able to take his family - especially the grandkids - to various cruises. It's a neat car.

I, too, have often stated that my pockets contain more lint than glint, and I truly enjoy making something from nothing....

I guess it's really your choice - with the proper caveats, of course.....

Either front-end would, apparently, need to be sectioned, so you need to decide exactly which one you want under your DeLightful DeSoto....

My M.O. would be to take the stock center link(s), and spend an afternoon at my local auto parts store - or auto recycling emporium - trying to find one that is as close as possible in geometry - but around three-inches shorter.....then section the crossmember to whatever difference exists between OEM and replacement center links. That should go a long way towards maintaining OEM steering geometry.

Although I have done it successfully in the past on some oval-track cars, I REALLY do NOT like to cut, weld, and sleeve steering components......but if it is your only option........................


me either but i did that to my old COE on the center link(non-wear item) because i wanted to use the center link from a van (4" wider) 60K under hard useage and never was a problem


My personal opinion is that  the p/u crossmember just might be the better option from a roll center standpoint......plus, it is almost like a M-II bolt-in, in that it is fully self-contained


well, everything but the box and idler....


whereas the Caprice would, likely, be a clip.

The p/u suspension geometry SHOULD have a higher roll center, which SHOULD work better with the higher CoG of the early car, resulting in a car that doesn't lean quite as much in the turns.

Also, alignment specs for Chevy/GMC pickups are listed at various ride heights, so finding a good alignment that tracks straight and doesn't wear tires might be a skosch easier.

Were you just a bit closer to Maine, I would probably swing by your shop one evening and try to talk you out of the Caprice front spindles/rotors  - or the entire chassis - to place in my "inventory" for use on a future racing project.


B.P.

[Ralph]

Thread thieves! Aah, that's OK as long as I'm learning something.  I think I might get the tie rod ends cut and rethreaded, to avoid the mismatched taper issue. Unless somebody can find one that's right for me.......

Oh, and can I get the word "Craftsman" removed from my avatar thingy and replaced with a more accurate "Backyard Hack-Job Artist" designation? Don't want people going around thinking I'm something I'm not! :oops:

Ralph

[1FATGMC]

Although I have done it successfully in the past on some oval-track cars, I REALLY do NOT like to cut, weld, and sleeve steering components......but if it is your only option........................

Were you just a bit closer to Maine, I would probably swing by your shop one evening and try to talk you out of the Caprice front spindles/rotors  - or the entire chassis - to place in my "inventory" for use on a future racing project. B.P.

Thanks Bob (you too Tom).  Looks like the PU is probably the way to go.  When this happens I'll let you know how it comes out (it will be at least a year as I have to get the b'ville car done first).  I don't have much of a parts house here and no salvage yard so cutting the center link might have to happen.  I'll try for a shorter one first when I go to New Mexico sometime.

If I part the Caprice out I could probably send you the spindles/rotors if it wasn't too much in freight or maybe relay them back there with some RRT guys or gals.  Now the chassis might be a different matter .  The car runs, but the 700R4 doesn't seem right.  I bought it for the 305 and the 700R4 for $300.  I plan on having the transmission rebuilt and upgraded and using it in the Limo along with some other parts from the car.  The 305 is a spare for the Buick I think a 350 would be better in the limo or maybe a 383.

c ya, Sum