Rubber VS Polyurethane

[Duff B.]

Hi All, I am a new member and owner of a 1972 LT-1 Convertible 45,000 original miles, built 2/21/72. I am about to do a frame off restoration and want to know if replacing the original rubber bushing/mounts (in good condition) with polyurethane would affect the value. Did this car come with the Smog A.I.R. system, if so where might I find the correct system. Thanks folks

[Alexander C.]

Re: Rubber VS Polyurethane

If anything, use polygraphite bushings. They will be a dark gray color and self lubricate so no squeaks.

Alex

[Kenneth T.]

Re: Rubber VS Polyurethane

Duff,

My question would be, Why? You have a wonderful forty year old car. Experience it as it was built. The C6 cars are faster and handle way beyond your car. That could also be said of some Ricers out there.

Your car will be a little tough on the butt, not be tight in the corners and too noisy to make your radio a smart decision. It is an old Vette and I believe that A.I.R. was on your car. Please take this in good humor as we all love these cars.

I switched my 71 off the Poly to the original bushings and I am happy with the ride and performance.

Ken

[Michael W.]

Re: Rubber VS Polyurethane

The more I see and learn about poly bushings the less I like them. They're the ideal marketeer's solution for a non-existent problem.

Your originals lasted for 39 years (so far)- what you would you gain?

[Rich W.]

Re: Rubber VS Polyurethane

I just did a 73 conv. rear suspension with rubber..dont think I would have liked poly since the car rides stiff now since new..I am with Mike with this also..changing the body mounts to poly I don't think is a good idea anyhow..I know I got cracks in my fiberglass..how many more would show up if the body was mounted with hard poly bushings..

[Duke W.]

Re: Rubber VS Polyurethane

With only 45K miles I doubt if the major load bearing suspension bushings even need to be changed unless it's spent a lot of time on jack stands with the suspension drooping.

When you get the various suspension components off you should be able to thoroughly check the bushings. If they're not deteriorated, just leave them in place.

If you do replace them use OE equivalent. Various aftermarket designs are really meant for race cars, not road cars.

I think all LT-1s had AIR, and this is the kind of thing where you need a JG to figure out what it should have.

Duke

[Joe L.]

Re: Rubber VS Polyurethane

Hi All, I am a new member and owner of a 1972 LT-1 Convertible 45,000 original miles, built 2/21/72. I am about to do a frame off restoration and want to know if replacing the original rubber bushing/mounts (in good condition) with polyurethane would affect the value. Did this car come with the Smog A.I.R. system, if so where might I find the correct system. Thanks folks

Duff-----


Personally, I would not even consider using polyurethane bushings. You'll lose more than you gain and you won't gain anything worth gaining for a street car. GM used rubber suspension bushings at least through C4 production. I believe that C5 and C6 also use rubber for all suspension bushings.

As far as AIR goes, ALL 1970-72 LT-1's were originally equipped with AIR. If anyone tells you different, they're wrong.

[Mark P.]

Re: Rubber VS Polyurethane

If your strut arm bushings are fine you should not change them if you are concerned about originality. You can't match the look with any of the repro bushings I understand.