E-Bodies.org Cuda Challenger Forum

Technical Shop => Wheels, Tires, Brakes, Suspension & Steering => Topic started by: billdogg5 on September 03, 2021, 07:17:52 AM

Title: Rear shock psi?
Post by: billdogg5 on September 03, 2021, 07:17:52 AM
74 challenger with original rear shocks, what air pressure do they take?

Thanks!
Title: Re: Rear shock psi?
Post by: Burdar on September 03, 2021, 07:45:04 AM
Quote74 challenger with original rear shocks

Stock air pressure was NONE.  74 Challengers didn't come with air shocks.
Title: Re: Rear shock psi?
Post by: DeathProofCuda on September 03, 2021, 07:45:17 AM
If you have air shocks in the rear of your car, they are not original.  Air shocks on a muscle car are usually used to adjust the stance of the car, so the pressure needed is based on how high you want the raise the rear end.  Just be aware that using air shocks to raise the rear of your car can damage the upper shock mounts.  Your leaf springs are designed to hold up the rear of your car, not your shocks.
Title: Re: Rear shock psi?
Post by: dodj on September 03, 2021, 07:47:28 AM
They aren't original, but likely added the first time the owner thought the car's butt was sagging.
If it were me I'd replace them with proper shocks.
There is no real good psi setting, if you want to keep them, just don't raise the back of the car much with them. It stresses the shock cross member too much.
Title: Re: Rear shock psi?
Post by: billdogg5 on September 03, 2021, 08:42:44 AM
Ok thanks for the responses probably look into replacing them
Title: Re: Rear shock psi?
Post by: billdogg5 on September 04, 2021, 03:37:45 AM
You guys have any suggestions for replacement shocks?
Much appreciated
Title: Re: Rear shock psi?
Post by: anlauto on September 04, 2021, 05:33:57 AM
You'll likely find that your car will be sagging in the rear end once you remove the current shocks, and regular or even heavy duty shocks will not raise it back up. :alan2cents:
Title: Re: Rear shock psi?
Post by: billdogg5 on September 04, 2021, 06:04:04 AM
Whats the proper way to raise the her?
Title: Re: Rear shock psi?
Post by: 76orangewagon on September 04, 2021, 06:17:13 AM
Quote from: billdogg5 on September 04, 2021, 06:04:04 AM
Whats the proper way to raise the her?

I took mine to my local spring shop and had them re-arched to factory specs..they also would have gone more if I wanted more lift and the cost was much cheaper than buying a new pair from one of the aftermarket spring companies.
Title: Re: Rear shock psi?
Post by: Mrbill426 on September 04, 2021, 08:10:11 AM

With the mention of air shocks putting stress on the upper shock mounts is it advisable to install (pressurized) gas shocks back there??
Title: Re: Rear shock psi?
Post by: dodj on September 04, 2021, 08:24:59 AM
I can compress a gas shock with my hands, so the spring is still doing the car lifting. Although a gas shock does increase ride height for a brief period.  So I don't think it is the same,  but interested in what others have to say.
Title: Re: Rear shock psi?
Post by: Mrbill426 on September 04, 2021, 01:01:18 PM
@dodj (https://forum.e-bodies.org/mlist/dodj_816) me too.  I installed gas shocks on mine, had to do it by connecting the top first because otherwise lying under the car I could not pull them in to slide upper bolts through if I did the bottom first.  When I released the "tether" I had one shot at looping the bottom ends over the pins as they extended...there was no turning back  :o ... They are locked in there now... the rear is "solid".  I suppose they might relax over time.  :dunno:



Quote from: dodj on September 04, 2021, 08:24:59 AM
I can compress a gas shock with my hands, so the spring is still doing the car lifting. Although a gas shock does increase ride height for a brief period.  So I don't think it is the same,  but interested in what others have to say.
Title: Re: Rear shock psi?
Post by: HP2 on September 05, 2021, 08:47:14 AM
A high pressure nitrogen shock is around 160-200 psi. This psi is transferred through the shock in a controlled rate by the valving. By comparison, an air shock pumped up to 100 psi holding up 45% of a 3800# car,  takes an 855# beating in each shock every time the suspension cycles and the pressure is a constant that sits in the bladder and is not valved to transfer the pressure.

Title: Re: Rear shock psi?
Post by: Chryco Psycho on September 05, 2021, 06:45:10 PM
Get a decent shock QA1 , Bilstein .
KYB is Junk
Title: Re: Rear shock psi?
Post by: 76orangewagon on September 06, 2021, 06:12:22 AM
Here's what WILL eventually happen to your rear upper shock crossmember if you use air shocks to lift the rear of the car instead of of the springs. 
Title: Re: Rear shock psi?
Post by: anlauto on September 06, 2021, 06:34:00 AM
That's a great example :o ....we need to keep those pictures on file :bigthumb:
Title: Re: Rear shock psi?
Post by: dodj on September 06, 2021, 09:10:43 AM
Those air shocks must have been extremely popular back in the day. Mine had normal shocks on it when I got it, but there was a schrader valve mounted in the trunk and a bit of tubing underneath.  :dunno:

It also had the rear valance missing and 5" or 6" 'clam digger' shackles out back to keep the bum up.
Title: Re: Rear shock psi?
Post by: MoparLeo on September 27, 2021, 11:27:47 AM
Shock absorbers do not support weight. The spring does. What a "shock absorber" actually does is to dampen spring action. The more proper name, used in Europe are dampers.
They try to keep the tire in constant contact with the road surface.
Gas shocks use a different internal system to separate the fluid chambers with a gas bladder. The purpose is to eliminate foaming of the fluid during rapid compression/rebound cycles. Not to support any kind of weight.
Air shocks are actually "air assist" shocks . Air bags have been used for Trucks for many years. The mounting system on trucks is built to a different standard than a passenger car.
As said before, it was a cheap/simple way to raise the rear of the car starting back in the 70's. Was never a good idea, more of a fad.