Self leveling rear suspension

[73 T&C]

ive been toying with the idea of installing a self leveling rear suspension on the NYB. I usually drive by myself but, occasionally, when I load up the family or some clients for lunch. The tail really drags.

Just got the “heart” in yesterday

The original stock system had a variation of the Cadillac system. But, rather than a combined vacuum driven compressor with integrated pressure vessel, the Mopar design had a separate vessel installed under the body. Also, the Mopar system operates with the movement of only one side (drivers) rather than the Cadillac system that makes adjustment based on the movement of the differential relative to the body.

I am planning a similar system with a center mounted adjustment valve body, separate pressure vessel in the trunk and vacuum compressor in the engine compartment.

 

[Triple Pickle]

ive been toying with the idea of installing a self leveling rear suspension on the NYB. I usually drive by myself but, occasionally, when I load up the family or some clients for lunch. The tail really drags.

Just got the “heart” in yesterday

View attachment 265665

 

[Triple Pickle]

How does that work? I’ve never seen such,myself. I always put air shocks on mine for such occasions.

 

[1978 NYB]

Runs off of engine vacuum through the brake booster and an air compressor under the left front fender mounted on top of the inner fender. Air line goes back to the an air tank under the frame near the middle of the car on the drivers side and then to an air line to a leveling valve on left side of the axle and then splits to both air shocks.

I have it on my 78 NYB.

 

[73 T&C]

Here’s the system from the FSM.

The NOS Delco unit I got is too big to install in the original location and will get cooked good from being next to the “blast furnace” 440. So I’m looking at actually mounting it to the front face of the drivers side inner fender.

But it’s obvious from the photo that the compressor is just the top half of the delco unit

 

[Triple Pickle]

Fascinating! I haven’t seen that setup.
If it’s reliable, I’d install it!

 

[1978 NYB]

Jav....

Be careful if you lift car by the frame. It will destroy the leveling valve and linkage.

 

[73 T&C]

Here’s what I mean....

This is the mopar (delco unit).

This is the combined compressor and pressure vessel as used in Cadillac cars of the era. It’s a big unit and will not fit in the original location. But, you can see it’s the same compressor unit with only a change in the fresh air inlet. (More on that later).

This is just the compressor unit (also by delco) that is part of a “Jacpac” kit I found on EBay.

 

[73 T&C]

Jav....

Be careful if you lift car by the frame. It will destroy the leveling valve and linkage.

You are 1000% correct Bob!

That’s the primary reason I’m setting the valve over the dif with a sissors connection. To give it enough room to move (when on a lift) without hitting the limits of the valve.

The Mopar system will work but has a bit more finicky geometry. I’m looking at a similar but hybrid system to be able to put a tap on the vessel and be able to fill a tire if I have to.... much larger vessel and mounted in the trunk in the drivers side fender well.... under some carpets.

hey...it’s my rabbit hole and I’ll do as I want. Stand by.

 

[commando1]

hey...it’s my rabbit hole and I’ll do as I want

 

[1978 NYB]

Good luck!

I have KYB Gas-A-Just shocks on the front and I'm super happy with them and I'm considering putting them on the rear too.

I was contemplating Bilsteins but they just are too stiff of a ride for the NYB. Maybe I'll put Bilsteins on my Ram down the road.

 

[commando1]

Just bag it...

 

[1978 NYB]

Just bag it...

The Ram or the NYB? LOL.

 

[73 T&C]

Just found this on EBay. Negotiations in progress for this NOS unit. There’s also another one but it’s used and untested.

 

[commando1]

The Ram or the NYB? LOL.

Yes.
Lol

 

[CBODY67]

I believe the later GM systems are a bit simpler, with a rear underbody mounted electric air pump. The "height" link goes to one of the rear control arms (independent rear suspension) which modulates the air valve. Using the later electric pump, rear-mounted, might be better than the vacuum-powered pump?

AND . . . of course you'll need the evil air shocks on the back! YIKES! Brace for the backlash of the "stronger springs" orientation! Be that as it may.

Keep us posted . . .

CBODY67

 

[1978 NYB]

You are 1000% correct Bob!

That’s the primary reason I’m setting the valve over the dif with a sissors connection. To give it enough room to move (when on a lift) without hitting the limits of the valve.

The Mopar system will work but has a bit more finicky geometry. I’m looking at a similar but hybrid system to be able to put a tap on the vessel and be able to fill a tire if I have to.... much larger vessel and mounted in the trunk in the drivers side fender well.... under some carpets.

hey...it’s my rabbit hole and I’ll do as I want. Stand by.

Please post many pictures as you progress as usual. Thanks!

 

[73 T&C]

Please post many pictures as you progress as usual. Thanks!

Will do. Still getting the “kit” together.

 

[1978 NYB]

Thanks Jav!