Suspension question

[Bama-man]

I have 1970 Plymouth Barracuda w/ a 440 and it seems very low to the ground it is supposed to be a 318 car so just wondering if the front engine cradle is wrong and maybe too much weight in the front end can anyone give me some ideas of how far off the ground it should be from the cradle to the ground, can't even get my floor jack under it.

 

[Challenger RTA]

 

[Challenger RTA]

Do you have the right torsion bars in?

 

[Bama-man]

not sure I bought this car as is, how do I find out if I have the right torsion bars in ?

 

[moparleo]

To get the front end up you need to turn the torsion rod adjusting bolts clockwise.
If the front end is too low for a floor jack, the answer is really pretty simple get a few sections of 2 x 4"s and put them in front of the tires.
Just drive upon them and you get 1 3/4" increase. If you want more just stack more wood or blocks until you get enough room for your floor jack.
Put it under the middle of the K member. The wheels/control arms will drop down
Now you can tighten up the torsion bars.
Really the torsion bars and shocks should be upgraded to H.D. units.

 

[Bama-man]

Thanks for pointing me in the right direction I will do more research in my Service Manual.

 

[Chryco Psycho]

If you clean off the end of the T bars you usually can read the # on the rear of the bar inside the socket.
the bars are adjustable using the bolt inside the lower control arm , make sure the weight is off if you try to adjust them .

 

[MoparCarGuy]

These should help with the Service Manual instructions from @Challenger RTA.
As noted earlier in this thread, it is advisable to take the weight off the front suspension before attempting to RAISE the suspension height. That is not as much of a factor if you are going to LOWER the suspension height but your bolts may be rusty. Apply a good amount of penetrating oil to the torsion bar adjust bolt threads and let them sit overnight to loosen them up.
The last thing you want to do is damage these bolts.

 

[MoparCarGuy]

More tips…
You can measure from your fenderwell lip to the ground after you get everything adjusted to specs and save it. That measurement should stay the same unless you change wheel or tire diameter.
Most consider it mandatory to get an alignment immediately after a ride height change.
There are some special alignment specs versus factory 1970 specs that you should share with your alignment tech.
Can someone share the alignment info?
I will look for those as well and post them.

 

[Chryco Psycho]

Max castor
1/2* negative camber
1/16" toe in

 

[MoparCarGuy]

I found those specifications for the alignment. They are from 2017 and were posted by @Chryco Psycho. Go figure!

Paraphrased from his post.

E bodies were delivered with bias-ply tires for the most part so the factory alignment specs do not work for radial tires.
The following assumes all of the bushings, ball joints, & tie rods are in good shape.
Changing the ride height by adjusting the torsion bars will affect settings & should be corrected first.
Optimum settings are
- Caster: get as much as the adjustment will allow usually barely 3° this is done by turning the front adjusters so the control arm is as far outward as possible & the rear adjuster so the arm is as far inward as possible. Installing Moog's offset upper bushings will get you more adjustment range.
- Camber: you want approximately 1/2° negative so the top of the tire is slightly inward, this adjustment is done with the upper control cam bolts as well so you may have to back them off slightly to get the camber right.
- Toe-in: should be 1/16".

I also had this chart stashed away which corroborates these setting goals.

 

[Bama-man]

Wow that's great information thank you very much.

 

[heminut]

Do you have the right torsion bars in?

The 440's did have heavier torsion bars than the 318 cars, but the 318 bars will work. Back in the day Direct Connection's racing manual actually recommended using the smaller torsion bars for drag racing! The reasoning was that the smaller bars, when cranked up to ride height, had more stored energy and would make the front end rise more on launch (with 90/10 drag shocks) to transfer weight to the rear tires.

 

[MoparCarGuy]

The 440's did have heavier torsion bars than the 318 cars, but the 318 bars will work. Back in the day Direct Connection's racing manual actually recommended using the smaller torsion bars for drag racing! The reasoning was that the smaller bars, when cranked up to ride height, had more stored energy and would make the front end rise more on launch (with 90/10 drag shocks) to transfer weight to the rear tires.

The reduced diameter torsion bars used in the Slant Sixes were less resistant to front end lift (equal and opposite reaction to the rotation of the rear axles/tires) which indeed transferred the weight to the rear tires for traction.

 

[Bama-man]

Well thanks for all the help. I got the front end raised up although not sure if it's too high I'm about 26 inches off the ground to the top of the fender well. I was wondering if anyone out there could measure their car and let me know if that's normal, not too sure, but looks a little too high above the tires.

 

[Chryco Psycho]

I usally set around 24-25" depending on tire size .

 

[moparleo]

Again. Post # 2 shows how to set it to the Factory number. It is never a fender opening height.
That is for looks, not a factory number.

 

[bc3j]

I usally set around 24-25" depending on tire size .

My fenders are 24.75” which is 15/16” by factory measurements. I have about 3/4” at the bump stops. I have a little grease on top of the bump stops to check if it ever hits the frame. Never does. Factory suspension.

 

[MoparCarGuy]

My fenders are 24.75” which is 15/16” by factory measurements. I have about 3/4” at the bump stops. I have a little grease on top of the bump stops to check if it ever hits the frame. Never does. Factory suspension.

@bc3j Did you choose 15/16" instead of 1-1/8" to get the look you wanted or to get within the typical 24-25" fender height?
I am preparing to lower my front suspension. Fender lip is at 27" and definitely too high. Tire/wheel combo is Goodyear Polyglas GT F60x15 on 15x7 steelies.

 

[Challenger RTA]

A little more on tire sizes.
Standard-Metric

Overall Wheel Diameter 78 series 14" Bias Ply 70 series 14" Bias Ply 60 series 14" Bias Ply 78 series 15" Bias Ply 70 series 15" Bias Ply 60 series 15" Bias Ply 75 series 14" Radial 70 series 14" Radial 60 series 14" Radial 75 series 15" Radial 70 series 15" Radial 60 series 15" Radial 50 series 15" Radial
21.8" - - - - - - - - 165/60 R14 - - - -
22.3" - - - - - - - - 175/60 R14 - - - -
22.7" - - - - - - - - 185/60 R14 - - - -
23.0" - - - - - - - - - 135/75 R15 - - -
23.1" - - - - - - - 165/70 R14 - - - - 205/50 R15
23.2" - - - - - - - - 195/60 R14 - - - -
23.6" - - - - - - - 175/70 R14 - 145/75 R15 - - -
23.7" - - - - - - - - 205/60 R14 - - 185/60 R15 -
23.9" - - - - - - - - - - - - 225/50 R15
24.2" A78-14 - - - - - - 185/70 R14 215/60 R14 155/75 R15 - 195/60 R15 -
24.6" - - - - - - - - 225/60 R14 - - - -
24.7" B78-14 - - - - - - 195/70 R14 - 165/75 R15 - 205/60 R15 -
24.8" - - E60-14 A78-15 - - - - - - - - -
24.9" - - - - - - 185/75 R14 - - - - - -
25.1" - - - - - - - - 235/60 R14 - - - -
25.2" C78-14 - - - - - - - - - 185/70 R15 215/60 R15 -
25.3" - - F60-14 - - - - 205/70 R14 - - - - -
25.4" - - - B78-15 - - - - - - - - -
25.5" D78-14 - - - - E60-15 195/75 R14 - - - - - -
25.6" - - - - - - - - - - - 225/60 R15 -
25.7" - - - - - - - - - - 195/70 R15 - -
25.8" - E70-14 G60-14 C78-15 - - - - - - - - -
25.9" - - - - - F60-15 - 215/70 R14 - 185/75 R15 - - -
26.0" E78-14 - - - - - - - - - - - -
26.1" - - - - - - 205/75 R14 - - - - 235/60 R15 -
26.2" - F70-14 - D78-15 - - - - - - - - -
26.3" - - - - - - - - - - 205/70 R15 - -
26.4" - - H60-14 - E70-15 G60-15 - 225/70 R14 - - - - -
26.5" F78-14 - - - - - - - - 195/75 R15 - - -
26.6" - - - E78-15 - - - - - - - 245/60 R15 -
26.7" - - - - - - 215/75 R14 - - - - - -
26.8" - F70-14 - - - - - - - - - - -
26.9" - - - - F70-15 - - - - - 215/70 R15 - -
27.0" - - - - - - - 235/70 R14 - - - 255/60 R15 -
27.1" G78-14 - - - - H60-15 - - - 205/75 R15 - - -
27.2" - - - F78-15 - - - - - - - - -
27.3" - - - - - - 225/75 R14 - - - - - -
27.4" - - - - - J60-15 - - - - 225/70 R15 - -
27.5" - H70-14 - - G70-15 - - - - - - - -
27.7" - - - G78-15 - - - - - 215/75 R15 - - -
27.8" H78-14 - - - - - - - - - - - -
27.9" - - - - - L60-15 235/75 R14 - - - - - -
28.0" - - - - - - - - - - 235/70 R15 275/60 R15 -
28.1" - - - - H70-15 - - - - - - - -
28.2" J78-14 - - - - - - - - - - - -
28.3" - - - - - - - - - 225/75 R15 - - -
28.4" - - - H78-15 J70-15 - - - - - - - -
28.7" - - - J78-15 - - - - - - - - -
28.9" - - - - L70-15 - - - - 235/75 R15 - - -
29.1" - - - - - - - - - - 255/70 R15 - -
29.3" - - - L78-15 - - - - - - - - -