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why can't i remove or cut the busings to lower the rear a little?

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Old 08-17-2016, 06:46 PM
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slickfx3
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Default why can't i remove or cut the busings to lower the rear a little?

has that been done?
Old 08-17-2016, 07:24 PM
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jim2527
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Rear suspension design is such that tension needs to be removed from the spring. i.e. The ends need to be lowered.

It's so cheap and easy to install longer bolts that it doesn't make sense to cut the lower bushings down. Cutting will only lower it a tick
Old 08-17-2016, 07:30 PM
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DUB
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Just do not lower the car so much that when it is sittign STILL...that the car is LEVEL.

The rear SHOULD be raised up a bit higher than the front for the transfer of weight ....which causes the rear to go down and the cars levels out.

If you get your car LEVEL when it is sitting still.....there is a chance that when you accelerate the front end of the car will be higher than the rear...which...in my opinion is not right at all.

DUB
Old 08-17-2016, 07:59 PM
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slickfx3
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~4" rear
~ 2 inches front
Old 08-17-2016, 10:18 PM
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slickfx3
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i changed the stacking order of the spring mount sandwich to cheese, and lettuce and tomatoes on the bottom, i could put the patty down there, it dropped 3/8"
Old 08-18-2016, 06:00 AM
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fishslayer143
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just use longer bolts.. simple
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Old 08-18-2016, 08:20 AM
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Kris_K
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Originally Posted by fishslayer143
just use longer bolts.. simple
Old 08-18-2016, 09:05 AM
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Kubs
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Originally Posted by slickfx3
i changed the stacking order of the spring mount sandwich to cheese, and lettuce and tomatoes on the bottom, i could put the patty down there, it dropped 3/8"
Are you saying the shorter pieces of the spring are now on the bottom? That is not correct. The spring is stacked the way it is in order to function properly. Moving them around can change the rate and effectiveness of the spring.
Old 08-18-2016, 09:42 AM
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slickfx3
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Originally Posted by Kubs
Are you saying the shorter pieces of the spring are now on the bottom? That is not correct. The spring is stacked the way it is in order to function properly. Moving them around can change the rate and effectiveness of the spring.
1982 composite
Old 08-18-2016, 09:50 AM
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keithinspace
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Just to satisfy our curiosity, what length bolts are in the suspension now? Stock? Or have you already put 8" bolts in and need to get more?

Also, is it a stock or aftermarket composite spring?

A picture of the car in profile would be helpful so we can see where you are and visualize where you'd like to be...
Old 08-18-2016, 12:31 PM
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69autoXr
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Originally Posted by slickfx3
has that been done?
I did it. Removed rubber cushions and replaced with 1/4" aluminum disks.
Old 08-18-2016, 12:56 PM
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Originally Posted by keithinspace
Just to satisfy our curiosity, what length bolts are in the suspension now? Stock? Or have you already put 8" bolts in and need to get more?

Also, is it a stock or aftermarket composite spring?

A picture of the car in profile would be helpful so we can see where you are and visualize where you'd like to be...
stock 6.5 " ? no 8" yet

stock spring

Old 08-18-2016, 12:58 PM
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slickfx3
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Originally Posted by 69autoXr
I did it. Removed rubber cushions and replaced with 1/4" aluminum disks.
can't i just use the old washers?

i just want 1 more "free" inch



when the car is unloaded in a bullit/Steve McQueen chase, do your discs clatter?

the compliance in that area is prolly not needed right?

Last edited by slickfx3; 08-18-2016 at 01:00 PM.
Old 08-18-2016, 02:56 PM
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69autoXr
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Originally Posted by slickfx3
can't i just use the old washers?

i just want 1 more "free" inch



when the car is unloaded in a bullit/Steve McQueen chase, do your discs clatter?

the compliance in that area is prolly not needed right?
I used aluminum so that there was no steel-on-steel contact. I don't notice any clattering, but I can't hear much over my exhaust. I removed the cushions specifically to eliminate the compliance rather than for lowering purposes.
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Old 08-18-2016, 07:09 PM
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Originally Posted by slickfx3
~4" rear
~ 2 inches front
You 'lost' me on this reply. I do not know that you meant by 4" rear and 2'' front

I have seen the photo of your car.

When I do a quick measurement on the Corvettes that come in from time to time with height issues. I take the tape measure and but it on the ground and run it up to the underside of the lip of the fender and quarter at the very top ( 12 o'clock position) and that is where I see if the rear is 1 inch above the front or not.

DUB
Old 08-18-2016, 07:22 PM
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fishslayer143
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It is a bad idea to put aluminum spacers in direct contact with the composite spring ends ..

Last edited by fishslayer143; 08-18-2016 at 07:23 PM.
Old 08-18-2016, 07:37 PM
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Originally Posted by fishslayer143
It is a bad idea to put aluminum spacers in direct contact with the composite spring ends ..
They actually are not...there is a piece of metal that garnishes the surface...so the aluminum actually does not touch the composite.

I can understand if you are referring to galvanic action....but that would take a while...depending on salt exposure and could be easily changed if the process began.

I myself would not use aluminum in this area....but that is just me.

DUB

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Old 08-18-2016, 07:47 PM
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Originally Posted by DUB
You 'lost' me on this reply. I do not know that you meant by 4" rear and 2'' front

I have seen the photo of your car.

When I do a quick measurement on the Corvettes that come in from time to time with height issues. I take the tape measure and but it on the ground and run it up to the underside of the lip of the fender and quarter at the very top ( 12 o'clock position) and that is where I see if the rear is 1 inch above the front or not.

DUB
measured tire to lip edge, the all different, but the rears are ~2-2.5" more gap than the fronts

by taking the top center spring spacer and putting it on the bottom, i dropped it 3/8 of and inch, i would like another 3/4 to 1 inch
Old 08-18-2016, 09:25 PM
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fishslayer143
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Originally Posted by DUB
They actually are not...there is a piece of metal that garnishes the surface...so the aluminum actually does not touch the composite.

I can understand if you are referring to galvanic action....but that would take a while...depending on salt exposure and could be easily changed if the process began.

I myself would not use aluminum in this area....but that is just me.

DUB
I would never use it that way.. GM learned with early C3s that aluminum spacers are NOT the way to go.. hence the rubber body mounts after 72 ... not to mention noise , and corrosion between the steel parts and the spacer.. and there is no flex in aluminum as the spring flexes thousands of times per day .. I just would never do it.. ESPECIALLY when all you need is two longer bolts!!!! how much simpler could it be?? and you keep the spring mounting as it was designed to be..

Last edited by fishslayer143; 08-18-2016 at 09:28 PM.
Old 08-18-2016, 09:27 PM
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keithinspace
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I apologize if this is too direct, but why are we even talking about this?

Go to Fastenal and get two 1/2" x 8" long Grade 8 shoulder bolts with nylock nuts. If you feel like you must, drill the end of the bolt for a cotterpin. I've been running nylock nuts for 4 years now and they haven't budged.

If the 8" bolts don't get you to where you want to be, then we can figure out how to get another little bit out of the suspension.


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