64 Pontiac Lemans Convert 6 cyl, 4 spd I've got a mess under the front end. The original owner said he had converted the brakes over to 1970 discs. The steering has always been extremely loose with a lot of binding sounds coming from the suspension. I had originally thought it was only the bushings but now I'm not so sure. I started researching replacement parts for the steering components and it appears to have a Chevelle drag link, idler and pitman arms installed. The springs are for the V8 not the 6, and one, possibly both upper ball joints are shot. The drag link is also bad. The upper A-arms have been over shimmed. 7 shims on the back bolt and 1 shim on the front. I'm not exactly sure what components have been installed, I just know the car sits a little high in the front from the springs, the suspension seems to bind a little and it has eaten a ball joint. Are there huge differences between the 64 and the 70 components? Not sure what to keep and what to get rid of. I'd like to keep the Chevelle drag link because it is much cheaper to replace than the original Pontiac unit. The car will eventually have a V8 in it so the springs need to stay. But the shims seem to indicate that someone was forcing the wrong pieces together. Any suggestions?
It's shimmed that way to increase caster. I think the spec is like -.5 degrees, but with radial tires it can be increased anywhere up to 2 -3 degrees if room allows so it can handle better. There isn't much differance between the 64 and 70 spindles , mostly because the 70 spindles have disc brakes.
An inch of shims lead me to think frame damage. Take it to a good alignment shop and get a real good front end man to give it a going-over.
The shim setup is identical for both A-arms. About an inch in the back and a single shim to the front. It is symmetrical from side to side.
I wouldn't rule out that possibility that somebody swapped an entire front suspension from a later model GM A body: including control arms, spindles, etc. Trust me, I've seen some hacked up stuff, and i wouldn't doubt that someone considered that they were being "smart" by swapping over the entire front suspension (no pesky ball joints to R/R). Those shims are weird- most of time they are used for minor camber adjustments/ and toe-in is adjusted through the tie rod sleeves, BUT it looks like someone was trying to correct a toe-in condition in the control arms/spindles- Ha! I wouldn't doubt that somebody could have the two top controls arms backwards- LH on the RH side/ vice versa..
Yea, that thought went through my head too. I'll have to verify that one. Any idea what the proper donor should have been for a disc swap?
take it to an alignment shop,those shims are in that position to add caster and they can see how close it is. Alignment specs are for factory ride height.
The alignment shop showed me the shims. They didn't know what to make of it. They also told me they couldn't check it because the ball joint and center link were shot. I'm in the process of collecting the correct parts to do it all at once and do it right.
Hotchkiss make suspension components for that car (incl. control arms)-- I bet you could find out by calling them or just looking through their catalog.
They should be fine together. Like I said it's to increase caster mostly unless there is other damage, I could see though if it was one side only the frame could be bent or something. Guys do this to a-bodies all the time for better handling with the higher caster with radial tires.
I thought you meant that just one A-frame had the stack of shims. If it's both it's probably mismatched components. Or as said elsewhere, the top A's are swapped side-to-side.
Im in the process of re-installing my upper control arms as well.The only problem is I forgot how many shims should be used on each side.I'm trying to not draw the upper to far in into the shock tower.I have already did it once on one side and broke the fitting to grease the control arm shaft kit.Thinking about maybe cutting a small hole on both sides of the shock tower to allow for clearance of the grease fitting.What do you guys think?Will it weaken it ?
Have you had it aligned at all yet? You said "steering has always been extremely loose with a lot of binding sounds coming from the suspension." Do yourself a favor and get a front end kit and replace everything, ball joints, bushings, tie rods, drag link, idler, etc. Check the adjustment in the steering gear box and the rag joint connecting it to the steering column. I've done a complete rebuild on 100k mile GM A-bodys that I thought drove decent. When I was done I was shocked at just how nice they can drive.
The 70 GTO disc brakes shouldn't be a problem. The Chevelle parts could very well be your problem. Even though they are both considered A bodies, they are not interchangeable between Chevelle and Lemans or GTO.
IIRC those cars were designed to run with negative caster. Considering that the stack of shims is on the back part it looks like someone was trying to run it with positive caster.
I don't know about that...I had a 69 Lemans that I converted to disc brakes that came off a 71 or 72 Chevelle and everything worked fine for me.
I had a 73 firebird that had spun a bearing on the spindle and they needed replacement. I copped a set off a mid 70's El Camino same as Chevelle. My 71 bird had perfect alignment with ZERO shims in the upper arms. The wheels were 90 degrees perpendicular to the road. After installing the Chevelle arms my tires were tipped in about 3-4 degrees because A-body and F-body have different kingpin/ball joint inclination angle. A line drawn through the upper and lower ball joints should intersect the road surface near the center of the tires contact patch for neutral steering. Old cars from the 30's and 40's have a kingpin inclination that puts the line on the instep of the tires contact patch. Road resistance then causes the tires to be forced into a toe-out stress keeping the steering linkages taught at speed and ***ist the manual box in steering. The old setup is more susceptible to things like rutted asphalt. The first generation a-bodies and F-bodies were an improvement to that however their suspension was outcl***ed by the 2nd generation F-body and improvements to the Chevelle design moving the steering elements to the front of the wheels The 2nd generation F-Body was the zenith of the parallel a-arm front/live axle rear suspension design. The move to struts by automakers was to lower production costs and allow a lighter unibody not because it was a technical improvement to geometry. Since a 2nd generation F-body has the most aggressive suspension geometry, my Firebird had more ball joint inclination angle. The Firebird a-arms were shorter than the Chevelles' because of the upper ball joints being moved in when they designed the 2nd generation F-body. The Firebird spindles had the top ball joint attachment, maybe 1/2" to 3/4" farther in from the wheel than the Chevelle spindles. Other than that they looked identical. I couldn't tell until I put them on. I'm ***uming the Chevelle a-arms were longer than the Firebird arms. It's also possible that if your suspension sits too high, the anti-dive angle of the a-arm shaft would cause the upper ball joint to move foreward as the a-arm travels down from where it is supposed to be.
Hey, just in case the previous owner didn't know what was actually converted to what, a few things to check on the spindles. The spindle height for an early a-body should be about 7 1/8" between the ball joints and the steering arms should bolt on. If the spindles are taller than this and the steering arms are cast into the spindle it could have had whats popular on these is the "tall spindle conversion" and would explain all the extra shims to make up for the taller spindle.
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