Corvette Forum : DigitalCorvettes.com Corvette Forums banner

1 - 20 of 21 Posts

·
Premium Member
Joined
·
10,261 Posts
Discussion Starter · #1 ·
I'm debating between taking my car to a frame shop to have them look at it or just taking measurements at home. Will a good shop have specialized tools and/or references to make the job more precise, or is it just going to be a guy with a tape measure and this drawing:


The driver's side front tire took the brunt of the impact so I'm mostly concerned about the width of the front part of the frame and the possibility of it being shifted off center. Any particular pointers for a home measurement job?
 

·
Registered
Joined
·
910 Posts
The part of the frame that bends fairly easily is at the curved part from the No1 body mount (the 17-1/8" measurement area).

You can measure all the centerpoints on your chart diagonally, you don't have data for that, just make sure the measurements are the same from side to side. If so, forget the shop.
Centerline of front crossmember hole to No 1 and/or 2 body mount holes diagonally should show if the front has shifted over. Use a plumb bob setup for each hole and measure between the string distances.
A good frame reference book will have more data than what you posted, but finding someone with that old a data might be tough.
They typically have hangers that set up a datum plane when the frame is lifted properly. Newer setups will use lasers.

Visit a couple shops and ask to look at their reference book/software. If they don't have the right equipment etc, move on.
 

·
Premium Member
Joined
·
10,261 Posts
Discussion Starter · #3 ·
thanks for the tips. I'll get a plumb bob setup and see what I find. Any idea what kind of tolerance would normally be acceptable?

My only concern measuring to the center hole of the front X-member is that the car has been jacked on that crossmember without a block of wood or anything to protect it so the bottom of the crossmember is somewhat dented. Hopefully that won't affect the location of that hole.
 

·
Premium Member
Joined
·
10,261 Posts
Discussion Starter · #4 ·
well, the good news is that the diagonal measurement from center hole of front cross member to body mount #1 matches within 1/8" from one side to the other. Driver's side is 41-5/16" and the passenger side is 41-3/16". I took a couple pics to show how I measured everything I'll post later.

I guess I'll skip the trip to the frame shop for the time being. I'm just going to re-assemble and see how the alignment goes. Hopefully I don't end up with a huge shim stack on either side to get it in spec.
 

·
Registered
Joined
·
332 Posts
what about frame twist? have you checked some of the vertical mesurements in the diagram.
On my 79 it has had a tap on the nose that has bent the frame where the nose support frame joins the main frame but it still steers straight with same shim stacks both sides and no tyre wear problems,so im leaving it alone for now.
Amazing what you can get away with on these old girls if you want to leave all the old bubba stuff alone:smack
 

·
Registered
Joined
·
3,100 Posts
Don't forget the frame horns- in front of the crossmember. Check from the front body mount out to the mount holes in them too- both the diagonal and the height from the floor.

Happy to hear the baseline is within 1/8". I bet there were lots of them left the factory that were not that close.
 

·
Premium Member
Joined
·
10,261 Posts
Discussion Starter · #7 ·
frame horns are dead nuts on 32-7/8". I'll take a look at some of the measurements from the floor. :thumbsup:
 

·
Registered
Joined
·
910 Posts
Most concrete floors are way of level and not straight or flat.
It's a real PITA, but the jacks must be leveled first to each other (or at least on the same plane) get an accurate reading. You can shim up the floor under the jacks.
If all of your diagonal measurements are OK, then twisting is unlikely.
 

·
Registered
Joined
·
355 Posts
I'm debating between taking my car to a frame shop to have them look at it or just taking measurements at home. Will a good shop have specialized tools and/or references to make the job more precise, or is it just going to be a guy with a tape measure and this drawing:


The driver's side front tire took the brunt of the impact so I'm mostly concerned about the width of the front part of the frame and the possibility of it being shifted off center. Any particular pointers for a home measurement job?
Just a piece of lead to get some points on the floor and cross measure between the point. The measurement should be fairly close. If not something is amiss and you need to check individual points.

The problem is that there are not much dimensions of the front suspension pick-up points, which are the most important. I'm doing the replacement of one of my lower A-arm mount brackets and didn't find any.
 

·
Premium Member
Joined
·
10,261 Posts
Discussion Starter · #10 ·
not much to see here, but I'll post anyway. Frame horns measure just fine:




Tied a string to the middle of a pen that I put up inside the crossmember and then centered the string on the hole.


Used an extra nut to hold the string on the bottom threads of each #1 body mount bolt. Since this puts the string off-center relative to the bolt I just made sure it was rotated the same on each side.
 

·
Premium Member
Joined
·
17,444 Posts
Come on Jason your Engineering side is showing. You are over thinking your project... You are trying to remeasure your frame to specs closer than its original design. The front and rear suspension has enough adjustment to compensate for 4 times the tolerances you are trying to measure to. It would take a flatbed frame jig to measure what you are trying to do.

Just get your front clip on and align the tires and drive the sucker...

:laughing::laughing::laughing:

One Old Mans Opinion...
 

·
Registered
Joined
·
2,488 Posts
Yea come on Jason,quite screwing around and put it back together,track day will be here soon.
 

·
Premium Member
Joined
·
10,261 Posts
Discussion Starter · #13 ·
I certainly didn't expect it to measure to within 1/8" even straight from the factory, but it didn't take much to measure, so it gives me some great piece of mind. I'm almost done futsing around with prepping and painting and all that business, so I'll be to the re-assembly stage soon.

Now if I didn't have to empty my "front clip budget" to pay my taxes I would have it ordered already...
 

·
Registered
Joined
·
2,488 Posts
If you are at a stopping point and are bored,you can always come over and help me finish removing the rear suspension,and pull the motor out of mine :D
 

·
Premium Member
Joined
·
17,444 Posts
If you are at a stopping point and are bored,you can always come over and help me finish removing the rear suspension,and pull the motor out of mine :D
What are you going to do after the first 5 min...:huh:
 

·
Registered
Joined
·
2,488 Posts
What are you going to do after the first 5 min...:huh:
scratch my head :huh: drink a beer or 2 :cheers: and then say :WTF have i got myself into now :laughing: and then call Ivan and SCREAM HELP!!!!!
 

·
Premium Member
Joined
·
10,261 Posts
Discussion Starter · #17 · (Edited)
hold off on pulling the engine until mine is driveable and then we can do a straight swap from yours to mine and not have to worry about taking the engine off the hoist ;):D
 

·
Registered
Joined
·
2,488 Posts
hold off on pulling the engine until mine is driveable and then we can do a straight swap from yours to might and not have to worry about taking the engine off the hoist ;):D
Not a problem Jason, we can slide her right into your car :thumbsup:
 

·
Premium Member
Joined
·
17,444 Posts
Not a problem Jason, we can slide her right into your car :thumbsup:
Might as well hold on. Does not look like we will be driving them for a while. Thinking about heading south for a while longer...
 

·
Registered
Joined
·
3,100 Posts
Yep. Sleet, freezing rain, 4" of snow, then more sleet. Almost makes me glad I'm not home.
 
1 - 20 of 21 Posts
Top