# Body Mount Bushings



## goat671 (Apr 13, 2019)

Hello
I am trying to decide if I want to use Rubber or if I want to go with a Polyurethane bushing. 
Has anyone used these from OPGI ?
Prothane
Bushing Kit, Body, 1965-67 Chev./Cut./1964-67 GTO, Conv., Polyurethane

If not these what and from who?

In general any advice or input is welcome on this subject.


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## armyadarkness (Dec 7, 2020)

Ive used poly on my 67. The ride is much harder and noisier now.


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## goat671 (Apr 13, 2019)

armyadarkness said:


> Ive used poly on my 67. The ride is much harder and noisier now.


I am looking to improve handling of the car I have updated to Hotchkis front and rear suspension including oversized sway bars.
Are you happy with your decision to go with poly?


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## 67lemans (Oct 30, 2009)

I used the rubber ones from Ames. I'm no engineer, but I can't imagine with so many of them on each side that there would be much handling difference between the two materials. The original ones I removed however were pretty bad in some cases.


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## armyadarkness (Dec 7, 2020)

goat671 said:


> I am looking to improve handling of the car I have updated to Hotchkis front and rear suspension including oversized sway bars.
> Are you happy with your decision to go with poly?


My car has Global West upper and lower control arms, with poly, all the way around, as well oversized sway bars, and new OEM coils. The ride is about as stiff as it could be, but not loose or "banging". Sure, it doesn't ride like a cream puff, but it also handles like a magnet, which is no easy task for a car that sits so high you can change the oil without a jack, or that is long enough to park in two different time zones. 

I also feel a lot safer when cruising at 85mph, and occasionally much faster.


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## goat671 (Apr 13, 2019)

armyadarkness said:


> My car has Global West upper and lower control arms, with poly, all the way around, as well oversized sway bars, and new OEM coils. The ride is about as stiff as it could be, but not loose or "banging". Sure, it doesn't ride like a cream puff, but it also handles like a magnet, which is no easy task for a car that sits so high you can change the oil without a jack, or that is long enough to park in two different time zones.
> 
> I also feel a lot safer when cruising at 85mph, and occasionally much faster.


Thanks for the input your setup sounds like what I am after


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## 67lemans (Oct 30, 2009)

I too went with poly on all the control arms and with new moog springs. Like armyad, my car sits pretty high and I like that, but it sounds like his budget might exceed mine! 

I'll have to update my avatar, that is the "before" height.


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## armyadarkness (Dec 7, 2020)

Yeah my car is HIGH! Which is exactly what I wanted. An intimidating stance was an essential element of my build... And with my components, there was no substantial loss in handling... Hence buying the best that I could.


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## Baaad65 (Aug 29, 2019)

I used polygraphite body mounts they're in between poly and rubber and they are black, got the whole kit even core support on line...they feel good to me.


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## goat671 (Apr 13, 2019)

Baaad65 said:


> I used polygraphite body mounts they're in between poly and rubber and they are black, got the whole kit even core support on line...they feel good to me.


Are these the ones? here What about the Bolts?


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## Baaad65 (Aug 29, 2019)

Yup but my kit came with bolts, think I found them on Ebay.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> I used polygraphite body mounts they're in between poly and rubber and they are black, got the whole kit even core support on line...they feel good to me.


That was what I went with on my '68. The polygraphite are said to be quieter than poly itself due in part to the graphite which acts as a lubricant.

Poly is harder than rubber. A car flexes more than you think - just jack up one corner of the car to change a tire, the whole side does not go up in the air, so the body/frame does have flex. The convertibles used the boxed frames for support as well as to help flexing. Jack up one of these cars and watch the door/fender gaps close up a bit. The boxed frames stiffened the car body and was why you could actually order the H.D. frame as an option for some years. Those guys who knew they were going to race/abuse their cars could order the boxed frame to stiffen it up.

As a side note, my brother had his '68 Bonneville jacked up kinda high in the air on just the 1 front tire side, like changing a tire, but I think he was working on the brakes. The windows were all rolled up. It was a real hot summer day. The twist in the body, the windows rolled up, and the heat in the car - blew out his side window all over the road like it had been shot out. He had a new window installed, but it was a lesson learned about putting twist into the body/fame and the possible results.

You can also purchase a kit to box an open frame if you feel you need this option.

So rubber mounts provide flex and dampens sound - which comes through the road/suspension/frame/body. Poly doesn't dampen sound too much and will flex far less so it does stiffen the car as it removes some of the frame/body flex. Next option is solid body mounts which ties the frame/body solid together - used primarily by racers where you don't want flexing of the body/frame as it can mean energy loss and reduce ET's in the 1/4 mile.


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## goat671 (Apr 13, 2019)

Can some one confirm the placement of the different bushings in this kit. 
From the service manual Bolt Positions 1,2,4,5,6,7 Look to mount the same way but OEM used different color combination for 1,2 both bushings violet. 
For 4,5,6,7 these used one violet and one blue.
Position 3 is on its own

So in the picture below 14 of the washers with small holes would be used between the bolt and the bushing. Middle two rows.

As there are 12 additional small hole washes would they be used on the top of the bushing between the frame on positions 1,2,4,5,6,7
The 12 small diameter sleeves are used in these positions

The 2 large hole washers are used on top of the bushing in position 3
Use the large diameter sleeves here.

The bushings pictured I see 10 at the top which I think are placed on top of the frame with the lip towards the frame why are there not 12?
What positions should get these?

12 in the center used at the bottom on the other side.

The six at the bottom 4 will be used in position 3

So the thing I can not figure out is what position should these 2 bushings be used?


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