65 Buick Skylark Circle track racer (suspension question)

In the spring I picked up this 65 Buick Skylark circle track racer cheap.

I'd seen it race before, hell I even raced against it in an Enduro race. It was slow, but I figured I could sort it out. And the price was cheap. It was just too cool looking not to buy. And did I say it was cheap?

The story is a couple guys built the car on a whim from an old parts car they had laying around. They had a sweet 65 Chevelle they had restored.

They raced it a couple times, did poorly, lost interest and sold it to me as "race ready".

Our versions of "race ready" differed, but it was still a killer deal. It has a full cage from a late model stock car in it. Came with 5 point harness, fire extinguisher, full gauges, and a few race rims. But the first issue I noticed is it still had drum brakes on the front. Ok if I'm restoring it, not so ok if I'm racing it. The rear end had been welded (found out later, badly) He admitted the "good race carb" had been removed and a junk carb put on. The motor ran on it, but badly. Also the springs had been cut and the car sat way too low. Too low to be legal. And I like more than 3 inches between my oil pan and the track.

So I paid for it, and dragged it home to fix it up to race. Rebuilt the carb, still didn't run good, but enough I could get it out on the track for a practice. The steering was really light and touchy. Something wasn't right. Got it home to start the real work on it. Long story short found out the timing was way off because the distributor was loose. Probably because the intake manifold had been off recently too. All the bolts for it were loose. Runs much better now!

The axle gears were replaced with a proper posi unit, and better gears. 3.08, to 3.73. Once I figured out what axle was in the car. The drive line has all been replaced. The motor is a low mile 350 from a 87 Chevy cube van, with a Turbo 400 tranny from I assume the same van. The axle the best I can figure is from an early 80's G body (Cutlass, Regal, Monte Carlo, Grand Prix)

I'm in the middle of tackling the front suspension. I've pulled it all apart and removed the cut springs. I think the right one must of came from the cube van too. It was huge! I got new springs, and I'm replacing the drums with the complete front spindles, rotors and calipers from a 2000 Sonoma. As well as the master cylinder and proportioning valve.

There is the intro to my project, now you are up to date. My problem now is caster. From what I understand, usually the top ball joint is farther back than the bottom ball joint. This gives you the feeling in your steering wheel, and what helps makes your steering wheel spin back to centre after a turn.

The less caster you have, the lighter the steering is, and it feels numb.

I figured this was my problem when I drove it. It was scary touchy, and I felt I could spin the wheel with my baby finger.

Well looking at my suspension which looks all stock, the upper ball joint is ahead of the lower ball joint. Opposite of what I expected to normally. I don't see any adjustments except for camber, which of course has the right wheel leaned over.

Any suspension gurus out there? What should I be looking for?

omg

sweet

Could it be something wacky like left arms swapped for right on a hastily-reassembled front end? This may not make any sense, but without knowing these cars, I don't know whether that's possible...

Maybe they even thought it would be a neat trick to quicken steering?

I have a uselessly out-of-context recollection from reading Circle Track 20 years ago that the left wheel would might use little, no, or even negative caster. Again, I've got nothing for context or detail, so best to chuck that out unless it rings a bell with someone...

That is pretty darn cool, and thanks for sharing. I'm going to move this from the build section to the general section. I think you'll get more help over there.

Do the Sonoma spindles bolt on to the 1960s A-body suspension arms? Are they the same height as the original spindle?

There are all kinds of aftermarket upgrades for that chassis available today but I don't know if they are legal for your racing class or in your budget. If I recall correctly, the big thing is changing the camber curve, and originally that was done by putting spacers on top of the spindles along with a whole bunch of shims on the upper control arm pivot.

You should try to get your hands on a factory shop manual to see what the original setup and settings were - a manual for any GM A-body car from 1964-1972 would work, they pretty much all had the same suspension.

Some times car use "wrong way caster" but my guess is the lowers were swaped side to side thus offset the outer ball joint wrong. Ask over on the WAR board http://www.auto-ware.com/autoware-bin/tech.pl?#34201 Board is full of gurus.

Offten in circle track the LF upper will be in front of the lower and the RF upper behind the lower to help jack weight in to the LF as you turn in.

44

I got some pics to show the negative caster.

Drivers side

Passenger side

stuart in mn wrote: Do the Sonoma spindles bolt on to the 1960s A-body suspension arms? Are they the same height as the original spindle?

Sorta. The spindles themselves are a 1/2 inch taller. But the real issue is the ball joints. As you can see the A-body ones are too thick to fit the holes properly in the Sonoma spindles. The nut threads on, but not enough to put a cotter pin through.

But after some research Sonoma lower ball joints do fit into the lower control arms of the A-body. The upper ball joints bolt in with 4 bolts. I'll have to drill holes for 2 of the holes.

I put it together temporarily until I get the new ball joints. As for the caster, I left it as is until I do some more research to see what it is supposed to look like. This is the Sonoma hub installed. But I do have to replace the ball joints.

I also got a set of springs for the car. I bought them off a guy who pulled them out of his 72 Nova Big block car, and installed lowering springs.

The spring on the far left was what was in my right front. The one beside that was the left front spring. The 2 springs on the right are the Nova springs.

This brought the car up to a reasonable height. We have a rule that the lowest part of the car has to be at least 5 inches off the ground. I have about an inch to spare now. Once I'm all done I'll check it again, but it seems to sit nicer now.

Found an old picture online from the previous owner as the before picture

And after.

Thus begins the new era in Grassroots Motorsports - Circle Track Cars become auto-x cars.

is there any reason you went with the metric brakes instead of just going to NAPA and getting rotors and calipers for a 70 Chevelle and buying or making brackets to keep the stock spindles? hell, a set of later (93- 02) Camaro rotors would almost slide right over the drum hubs and a caliper bracket could be easily made out of some 1/4" steel.

i have no idea what kind of steering geometry you will get with those spindles on that car- i don't think i've ever heard of anyone putting that setup on an older A body, but the 73-96 A/B body spindles are a common swap that is called the "tall spindle" swap and that leads to goofy bumpsteer issues.. i have heard of people putting the old A body spindles on the "metric" G bodies for circle track racing because they are lighter and stronger, but not the other way around.

regarding alignment: you adjust the alignment by stacking shims between the cross shaft on the upper arm and frame- the shim stack in the rear stud will always be thicker than the front stack.. this is how you set the caster and camber. set the caster first, then camber, then toe.

All this is well and good, but do all the pixels work?

novaderrik wrote: is there any reason you went with the metric brakes instead of just going to NAPA and getting rotors and calipers for a 70 Chevelle and buying or making brackets to keep the stock spindles?

I was told drum spindles are different than caliper spindles, so I would also need to find the spindles somewhere. Not a lot around here in the wreckers anymore. Budget is another consideration. This is an enduro car. Not too much money goes into these cars because they tend to get wrecked. I went with the Sonoma spindles because they are plentiful in the wrecking yard, and I get them for free as sponsorship.

Thanks for the tip on adjusting the caster. I wasn't sure how much adjustment I would get doing that. But looking at the car I have no shims on the drivers side, and a ton on the passenger side. And the 2 bolts on the passenger side have the same amount of shims on them.

I am betting that the upper A arm's are reversed side to side. I was thinking you may be able to swap the lowers and or swap both upper and lowers side to side but I think that this would screw up the end links on the sway bars. I would start with the uppers and measure things.

The '65 only had 1/2 to 1 1/2 degrees caster. With 1 being the preferred setting.

those lowers look reversed? is that the same frame family as the chevelle?

The lowers are on the correct sides, just not much caster stock on those cars.

The difference between drum and disc spindles is the upper bolt boss is shorter for disc brakes, but the drum spindle can be modified. I do understand using what you can get for sponsorship.

warpedredneck wrote: those lowers look reversed? is that the same frame family as the chevelle?

Yes, The Chevelle and the Skylark are basicly the same car for this generation. Both A-bodies.

All of the a arms appear to be in the correct place. Start with shimming them like Novaderrik said. on the earlier chassis we would need quite a few shims on the rear bolt. You may find it easier to get longer bolts and use a 3/4 inch long piece of pipe as a spacer so you dont have a big pile of shims waiting to fall out. What are you looking to use the car for? We ran a Pontiac on a 1/4 mile oval and we needed a heavy right front spring to get it to turn. If I remember right it came from a 70's Caddy. We cut it short and then shimmed it to get the proper ride height. We always had welded rears as well but you needed stagger to make them turn. It seems that stagger is al but impossible to get in radials.

HappyJack wrote:

novaderrik wrote: is there any reason you went with the metric brakes instead of just going to NAPA and getting rotors and calipers for a 70 Chevelle and buying or making brackets to keep the stock spindles?

I was told drum spindles are different than caliper spindles, so I would also need to find the spindles somewhere. Not a lot around here in the wreckers anymore. Budget is another consideration. This is an enduro car. Not too much money goes into these cars because they tend to get wrecked. I went with the Sonoma spindles because they are plentiful in the wrecking yard, and I get them for free as sponsorship. Thanks for the tip on adjusting the caster. I wasn't sure how much adjustment I would get doing that. But looking at the car I have no shims on the drivers side, and a ton on the passenger side. And the 2 bolts on the passenger side have the same amount of shims on them.

drum and disc spindles are made out of the same forging, with only one very minor difference.. the upper boss where the big anchor pin on the drum brakes threads in is machined down about .6" to make it into a disc spindle... 5 minutes with a hacksaw or 30 seconds with a cutoff wheel- after carefully marking the boss with the caliper brackets- is all that it would take to make your drum spindles into disc spindles. you don't even need to take them off the car to do it.

also, they made a production change sometime in the 66 model year where they made the hole in the upper boss one size bigger- 5/8 fin thread in place of 9/16" fine thread- and the holes where the steering arm bolts on was upgraded from 7/16" to 1/2".. but they kept using the same forging until they stopped making the 74 Nova, and you can upgrade the 64-mid 66 spindle and steering arm to the later spec pretty easily.

here is a decent writeup on the differnces between drum and disc spindles- he keeps saying "Camaro" spindles, but the 67-69 Camaro and Firebird used the same spindle, as did the 68-74 X body (Nova, etc.). scroll about 2/3 of the way down to where it says "THE CAMARO DISC BRAKE SPINDLE REVEALED!"..

http://www.pozziracing.com/brakes.htm

novaderrik wrote: i have no idea what kind of steering geometry you will get with those spindles on that car- i don't think i've ever heard of anyone putting that setup on an older A body, but the 73-96 A/B body spindles are a common swap that is called the "tall spindle" swap and that leads to goofy bumpsteer issues.. i have heard of people putting the old A body spindles on the "metric" G bodies for circle track racing because they are lighter and stronger, but not the other way around.

You might be surprised at how similar the spindles are for A, G, F, and S-trucks are. Its not a massive change. He should be fine.

HappyJack wrote: I got some pics to show the negative caster. Drivers side

I think you may be over-worrying. You absolutely positively cannot judge it by a full-droop suspension. Take a look at how the GM lowers swing forward as they come up. Most GM uppers have more shims stacked in the back to get the proper caster, so they swing back as they come up.

Leave the springs out, jack up the arms to about ride height and re-assess your situation. I think you'll find that its A-OK. The lowers are installed on the correct side. The uppers appear to be on the correct side. They also appear to be original A-body arms.

curtis73 wrote:

novaderrik wrote: i have no idea what kind of steering geometry you will get with those spindles on that car- i don't think i've ever heard of anyone putting that setup on an older A body, but the 73-96 A/B body spindles are a common swap that is called the "tall spindle" swap and that leads to goofy bumpsteer issues.. i have heard of people putting the old A body spindles on the "metric" G bodies for circle track racing because they are lighter and stronger, but not the other way around.

You might be surprised at how similar the spindles are for A, G, F, and S-trucks are. Its not a massive change. He should be fine.

i know they are similar, but the placement and length of the steering arms causes some crazy bumpsteer issues if you put a "tall" spindle in a 78-88 G body or 64-72 A body.. you also lose some steering ratio due to the longer arm. it can be overcome, but i wouldn't want to be custom modifying a spindle that stands a very real chance of getting mangled in the practice laps the first time out.

the latest craze in making the old A bodies handle is to use a tall upper balljoint to get the geometry benefits of the "tall" spindle without moving the steering arm in relation to everything else- but of course that's for street cars and corner carvers, and not something that's designed to go only left..

novaderrik wrote: i know they are similar, but the placement and length of the steering arms causes some crazy bumpsteer issues if you put a "tall" spindle in a 78-88 G body or 64-72 A body.. you also lose some steering ratio due to the longer arm. it can be overcome, but i wouldn't want to be custom modifying a spindle that stands a very real chance of getting mangled in the practice laps the first time out. the latest craze in making the old A bodies handle is to use a tall upper balljoint to get the geometry benefits of the "tall" spindle without moving the steering arm in relation to everything else- but of course that's for street cars and corner carvers, and not something that's designed to go only left..

I see what you're saying. I don't think I would go as far as to say "crazy bumpsteer" especially on something that is tightly sprung, but there are definitely trade-offs, bumpsteer being one of them.

The tall balljoint may be a perfectly good solution, but I just don't trust that much "bolt" in high-punishment areas like ball joints.

... and please don't ask how I welded mild steel to cast iron to modify my spindles

the tall ball joints are a proven deal- they are an oem part for a different application that just happens to fit the taper if the spindle and the a-arms and not some shady aftermarket junk sold to ignorant masses. Howe sells some, as does Addco, and a couple of places that repackage Moog parts.

Back in the '60's wierd things were done with suspensions. Particularly fronts. It may even have caster gain.

In order to check the caster the suspension needs to be a ride height, not at full droop.

Yes, it is a rookie mistake. I'm looking at the caster at full droop, not ride height. Oops.

I've checked it at ride height now. Still positive caster, but only slightly. Which seems to be the norm for these cars. +1 degree.

Also I got thinking, I don't think this car had power steering originally. So positive caster would make the steering lighter. Now it does have power steering, so it is super light. Maybe I should try disconnecting the power steering...