Trunk torsion bar to shock swap

[Rktpwrd]

I’ve done it on The Juggernaut, pretty simple to do with readily available gas struts. I don’t have any pictures ATM, but if I think of it later I’ll post them here. (Unless anyone cares to go digging through the build thread to find some…😁)

If you choose to do it the way I did, some strengthening/reinforcing of the lower mounting points is strongly recommended to avoid bending the weatherstrip rail, but that’s about it. It’ll make sense when you see how I did it.

 

[Rktpwrd]

Here ya go.
I did it to gain clearance to my air management system, but have also had issues with sub box clearances etc in the past so I understand the interest in converting.

I riveted a small bracket with the ball stud already attached to the trunk weatherstrip channel, used rivets so the weatherstrip would go back on nicely without having to notch it around bolts or what have you. Note the bracing I referred to earlier. Without it there’s a very good chance that you’ll bend the weatherstrip flange with repeated use.

The location was determined by a little trial and error experimenting with compressed and extended lengths.

The plug adjacent to the ball stud on the lid side is so that you can access the backside and bolt the ball stud in place without having to weld it on.

The shocks are 60 lb and work great for holding it up without any issues. If you have a spoiler mounted to the trunk lid however, you’re going to have to up the lb rating a bit to compensate for the additional weight.

Not saying this is the way it has to be done, but it’s what worked for me.

 

[pagrunt]

Here ya go.
I did it to gain clearance to my air management system, but have also had issues with sub box clearances etc in the past so I understand the interest in converting.

View attachment 190190

View attachment 190186

I riveted a small bracket with the ball stud already attached to the trunk weatherstrip channel, used rivets so the weatherstrip would go back on nicely without having to notch it around bolts or what have you. Note the bracing I referred to earlier. Without it there’s a very good chance that you’ll bend the weatherstrip flange with repeated use.

The location was determined by a little trial and error experimenting with compressed and extended lengths.

View attachment 190188

View attachment 190189

The plug adjacent to the ball stud on the lid side is so that you can access the backside and bolt the ball stud in place without having to weld it on.

View attachment 190187

The shocks are 60 lb and work great for holding it up without any issues. If you have a spoiler mounted to the trunk lid however, you’re going to have to up the lb rating a bit to compensate for the additional weight.

Not saying this is the way it has to be done, but it’s what worked for me.

Looks better than the GM fix with those bigger cylinders that twist the hinges & cause the hinge to lid bolt washers to cut holes into the trunk lid.

 

[79 USA 1]

Just a heads up, Many of the 78 & 79's were equipped with aluminum trunk lids. You can tell by the weight, a magnet and a quick visual is the support punch outs on the underside.

Aluminum vs. Steel

 

[OldsZZ383]

I immediately figured out that you needed more space. I've had both types. The current car I have, an '81 Cutlass ex-diesel has the shocks. Ever consider a broom in the trunk?

 

[Drkuhar]

Here ya go.
I did it to gain clearance to my air management system, but have also had issues with sub box clearances etc in the past so I understand the interest in converting.

View attachment 190190

View attachment 190186

I riveted a small bracket with the ball stud already attached to the trunk weatherstrip channel, used rivets so the weatherstrip would go back on nicely without having to notch it around bolts or what have you. Note the bracing I referred to earlier. Without it there’s a very good chance that you’ll bend the weatherstrip flange with repeated use.

The location was determined by a little trial and error experimenting with compressed and extended lengths.

View attachment 190188

View attachment 190189

The plug adjacent to the ball stud on the lid side is so that you can access the backside and bolt the ball stud in place without having to weld it on.

View attachment 190187

The shocks are 60 lb and work great for holding it up without any issues. If you have a spoiler mounted to the trunk lid however, you’re going to have to up the lb rating a bit to compensate for the additional weight.

Not saying this is the way it has to be done, but it’s what worked for me.

Ive never put the shocks on that i came up with but after looking at your pics, your way is way better than these gm shocks that clamp to the hinge arm. Definitely a better idea

 

[Turbo Zach]

I am no expert on what came on what. In my experience more than not the Third generation Monte's came with aluminum trunk lids. Out of 26 of them we owned three were steel. My 81 Century has small gas shocks. Maybe that would be an option?

 

[303'505rollin]

My 81 Monte Carlo has the gas shocks like in the pix shown I got a custom box made from accent auto sound back in 2000 or so and it was nicely built hugging the under shelf and angle down to floor and it left a decent amount of space for stuff. Made for 12s. On the 78-80 MC I've hade both trunk lids but when I put the aluminum one on the 80 it nearly knocked me in the teeth when I popped the trunk had to put the steel one back on. Didn't know about the bar adjustment then

 

[Turbo Zach]

My 81 Monte Carlo has the gas shocks like in the pix shown I got a custom box made from accent auto sound back in 2000 or so and it was nicely built hugging the under shelf and angle down to floor and it left a decent amount of space for stuff. Made for 12s. On the 78-80 MC I've hade both trunk lids but when I put the aluminum one on the 80 it nearly knocked me in the teeth when I popped the trunk had to put the steel one back on. Didn't know about the bar adjustment then

Please explain the trunk bar adjustment. My black car has an aluminum one off a different car and when you pop the trunk you better have a hold of it! I figured my car originally had a heavier steel trunk lid from the factory. I never really looked into it any, but would be a good thing to change on my car.

 

[464ChillerTech]

Here ya go.
I did it to gain clearance to my air management system, but have also had issues with sub box clearances etc in the past so I understand the interest in converting.

View attachment 190190

View attachment 190186

I riveted a small bracket with the ball stud already attached to the trunk weatherstrip channel, used rivets so the weatherstrip would go back on nicely without having to notch it around bolts or what have you. Note the bracing I referred to earlier. Without it there’s a very good chance that you’ll bend the weatherstrip flange with repeated use.

The location was determined by a little trial and error experimenting with compressed and extended lengths.

View attachment 190188

View attachment 190189

The plug adjacent to the ball stud on the lid side is so that you can access the backside and bolt the ball stud in place without having to weld it on.

View attachment 190187

The shocks are 60 lb and work great for holding it up without any issues. If you have a spoiler mounted to the trunk lid however, you’re going to have to up the lb rating a bit to compensate for the additional weight.

Not saying this is the way it has to be done, but it’s what worked for me.

Rktpwrd you don’t happen to know the length of strut that you used or a p/n? I’m going to need some more clearance for speakers and thinking that this is the way I would like to go. Thanks in advance for any info.