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Discussion Starter · #1 ·
Last week my car had 60mm taken off one side and 40mm of the other to get sitting closer to right. Front to back on the RHS (driver) it is good, with about a 0.5 degree rise in the rear which should be lost with settling and make it exactly level.

But looking at it from the rear, it sits about 10mm lower on the driver's side. And the bumper is not quite level, so it looks a little worse than it actually is

We can get the bumper right without too much trouble. But to alter the position of the body, would I be looking at adding a 10mm raising block to one side, or start shimming the body mounts in increasing amounts towards the rear?

It's a Sports Coupe, so pretty flexy. And the gaps, as they are, are all good.

The mechanic is voting for shims. I'm voting for a block (and longer U bolts).
 

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A buddy of mine had his levelled by using lowering blocks at the rear.

He had it done at a suspension place, they took seveal measurements to what my buddy wanted the stance of the car to look like, after he was happy with the look they went ahead and made the lowering blocks to suit.
 

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Discussion Starter · #3 ·
I am kind of guessing that doing it with shims to the body mounts would be a trial.

10mm would be added to the rear mount, then 7.5mm to the next, then 5 and 2.5 respectively across 4 mounts to the middle – it's a hard top. And I'd be betting that it would change the gaps to the doors. (I saw how much the gaps change when jacking the car from the front end of a chassis rail.)

Where these cars ever shimmed on the body mounts from factory?
 

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Discussion Starter · #5 ·
Don't even think about the body mount shims.
I know my chassis was dead straight and level when it was done – an expert measured it against the factory specs. And the body was set to it with a new set of mounts – and I have no reason to believe there were any issues in that process, the body guy being very familiar with 567 Chevs.

I wonder why it might not be straight. We are looking at it from the rear on a flat workshop floor; the car looks to be up on one side (the passenger side) and the measurements are giving a 10mm difference. The springs were re-set a week ago and re-installed. The re-re-installed swapping sides and it made no difference – and the springs themselves measured to be exactly the same.

I know lowering one end of the bumper will help. But I am reluctant to move it too much, since the gaps with the tail lights are good. Maybe 5mm will do it and then it will be in line with the trunk lid edge.

Maybe I'll just put some weight in there and loosen off the hinge shackle and let it sit for a bit. Or drive it a bit and see where it settles.

Prefer to do this than get to it with shims, truth be told. Even a 5mm lowering block I would not mind.
 

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Where are you measuring the height? You should measure from the ground to the bottom of the side sill on both sides. Also, ground which you may think is level may be not quite level. Measure with the car facing one way, then turn the car around in the same spot and remeasure. While you're doing all this, measure from the ground to the bottom of the frame rails.

You should measure at the front and the rear of each sill, at the front of each side's frame horn, at the rear of each side's rear bumper mount, at each side's rear shock mount and at each side's front lower ball joint. Make sure you have the same size tires on each side (duh!) and that the tread wear and the air pressure is the same. Doing all this will identify exactly where the difference in measurement is and will lead to corrective measures.

If the frame measures level and the body doesn't, then the mounts may need to be shimmed. If the frame doesn't measure level then the suspension is the culprit. It's a big job but you coud switch the rear springs sde-to-side. It's also possible, but not likely, that one of the coil springs has rotated out of the pocket in the A-arm.

Remember, the weight of the spare tire and jack being there, or not there makes a small difference, as does steering gear on the right side of a car designed for it to be on the left. And, a full tank of gas weighs almost 90 pounds more than an empty tank, again making a not so small difference.

Really, a 10mm difference (about 3/8" to us 19th century folks) is barely enough to really notice.
 

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Discussion Starter · #7 ·
Thanks, David. Some good information there.

I've got a deal of that all covered:

  • This is rear springs only.
  • New tyres are on, and filled equally.
  • Have swapped leaf springs from side to side – no difference.
  • Tank is 1/4 full – and look forward to the improvement when full! Final measurements will be taken when 3/4 full.
  • Spare wheel is in.
  • Jack is in.
  • Main measure for height difference is the rear of the sills.
  • Workshop floor is dead level.
... So on that basis, the variables are reduced.

Like I said, I'll see what difference just tweaking the bumper makes in the first instance and go from there after it has had a bit of time to settle.
 

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Discussion Starter · #8 ·
Were these cars ever shimmed on the body mounts from factory?
 

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Is it diagonally out? Ie: opposite difference at front. Like jacking up a car, a slightly raised front corner compressing the diagonally opposite rear???
 

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Discussion Starter · #11 ·
Pretty sure it's level across the front. But I am going to sight and measure it all tomorrow.
 

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Discussion Starter · #12 ·
Matt, I checked it with a tape this morning, and it's actually low along the whole driver's side. A wee bit less out at the front, admittedly. Must be the bumper that makes the rear look worse. So, we'll shim one side. The mechanic reckons it's a 45 minute job with a 4-poster. Flippin' heck, it takes me that long to change oil!
 

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Sounds like you are close to getting it sorted. It would be interesting to see the effect of shimming up the low front spring with an insulator to see what if any effect that had, but sounds like you've got a plan.

And congratulations on the first drive. What an achievement after so long!

Any planned events to take it to? Bacchus Msrsh swap and show is October 20.
 

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Discussion Starter · #14 ·
Any planned events to take it to? Bacchus Msrsh swap and show is October 20.
Thanks, Matt.

The car was invited to be part of the Motorclassica Concours 25-7 October.

Then I guess I will get it to John's Picnic – an event that I really love.

It will also be in the Hotrod Show at the Exhibition buildings in January.

The whole show circuit is not really my thing, but it's kind of fun to give it an outing while everything is still clean – and let people check it out. Then it will be weekend drives, Camperdown and club runs, etc.
 

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Discussion Starter · #15 ·
Ok, I measured it up myself today. Chassis to the ground.

Front is low 10mm on the right.

Rear is low 15mm on the right.

So the chassis wasn't as level as the guys at the shop had said.

I think shimming is out. I never really warmed to the idea anyway, since it had been set through a few session already and I just didn't trust the movement of the front clip on the central mount point.

Looks like we can either:
  1. Re-set the rear left spring – to take it down (and that will bring the front right up a bit).
  2. Put a 10mm lowering block on the rear left spring.
  3. Put a spacer on the top of the front right coil.

The mechanic at the shop is getting a spring guy back to give an opinion.
 

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John
I have been down that road a time or two. Once the only fix was to change the air inflation on the tires to square it all up.

That said, I would drive it a while and let everything settle in, you will be surprised at how much it will settle from use.

Don't fret over it, just drive it a while then see what happens.

Mikey
 

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John
I have been down that road a time or two. Once the only fix was to change the air inflation on the tires to square it all up.

That said, I would drive it a while and let everything settle in, you will be surprised at how much it will settle from use.

Don't fret over it, just drive it a while then see what happens.

Mikey
I agree, mine did settle down with use, yours is not out enough to be worried too much about.
Cheers, Rod.
 

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You still need to take detailed measurements and compare each side to see what's out of whack before you can do a fix. Don't waste your time and money replacing things until you know for sure where the problem lies.

In the rear I'd suspect one of the spring shackles may be hung up. In the front it could be the spring, ball joints or A-arm bushings.

Also, make sure your shocks aren't hanging up. Disconnect them and see what that does.

By the way, it's a good reminder to us seppos that your show season is just beginning while most of us are buttoning up for the bad weather.
 

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Discussion Starter · #19 ·
I let it settle a bit. 24 hours. No change! :)

Since it's headed for a show this week, we decided to re-set (lower) the rear passenger side spring again by 10mm. And that helped. Then put a spacer above the front driver side coil, and that put the front right as well. All good. Just a wee tweak to the rear bumper alignment and the gaps to the tail light housing above c/o a die grinder to the slots (from behind) and all's looking pretty sweet.

Now I don't want it to settle. :)
 

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I let it settle a bit. 24 hours. No change! :)

Since it's headed for a show this week, we decided to re-set (lower) the rear passenger side spring again by 10mm. And that helped. Then put a spacer above the front driver side coil, and that put the front right as well. All good. Just a wee tweak to the rear bumper alignment and the gaps to the tail light housing above c/o a die grinder to the slots (from behind) and all's looking pretty sweet.

Now I don't want it to settle. :)
Which show you heading to on the weekend? There are a couple of good ones on. Which club did you end up joining John?
 
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