early A & front chassis stiffening

-
3

340duster340

Well-Known Member
Joined
Jun 20, 2004
Messages
1,315
Reaction score
153
Location
long island NY
what have you folks done to stiffen up your front suspension?

i have my 66 torn apart and its built like a beer can. the shock towers are cracked and previously re-welded + the k looks flimsy in comparison to the later style a bodies.

i am thinking of boxing the k-frame and gusseting where possible, plus reinforcing the shock towers some how.
 
What kind of beer? :)

Look into the front stiffeners that run on the outside of the fenderwell liners (inner fender)
They run from the firewall down across the top of the shock towers and continue down to the frame rail.
I'll see if I can find a picture for you.

This is our member crackedback's car, and I realize yours is designed a little different but the general idea applies.
 

Attachments

  • mydart586.jpg
    18 KB · Views: 1,428
I think you're on the right track. The early A's were light, but you can watch the front end flex... I plan to fab up subframe connectors, torque boxes and inner fender braces similar to what US Car Tool sells for the later cars http://store.uscartool.com/70-75-a-body-chassis-stiffening-kit.html That is unless they need a Beta tester for early A kits about the time I get mine back on the road.

The early K can be boxed and welded like this http://www.firmfeel.com/a_body_mopar_k_frame_reinforcement.html
 
Is it degraded from years of rust. Any donor cars near u with good towers to weld in as replacements?
 
chewy said:
Is it degraded from years of rust. Any donor cars near u with good towers to weld in as replacements?
Click to expand...

Maybe maybe not but there was no mention of rust, just wishes to stiffen it
(which most of us do) and cracking of shock towers.
The cracking could be a case of being driven hard, and the body flex also.
 
I have made and used a "monty carlo" bar like the early mustangs liked. After a few years the paint may crack next to where mounted. Design it around your engine and car. Cost about 10 bucks and your time.
Have the subframes been connected yet? I have found that to remove hard to find rattles also. The door jambs were moving while driving.
 
hi all, rust no so much an issue for the structural bits, so its really just to beef things up since the shock towers were cracked, granted the car probably has 100K+ miles on the body and these were not built too well to begin with.

amx - do you have any pics of the monte carlo bar you are running?
 
Have you looked into or installed the torque boxes? Those and sub frame connectors ( already mentioned ) will help reduce body flex as well.
 
i will also be installing subframe connectors, but the cracked shock towers have me spooked. i am leaning toward fire wall bars that tie the wall, shock tower and front frame rail.
 
No pictures of installed of either car. One was 70 Barracuda other was 69 AMX. However you design for fit, be sure to be able to remove it for service work. Each car is different on where to connect for best benefit. These were done in mid 1980's. You could also tell the difference when driving hard.
 
I'm planning to move the shock tower extension leg inwards until it is flush with the inner fender and then spot weld that area as well. The 4 spot welds between the shock tower and inner fender are not enough.

Charlie
 
Mopar shock towers are NOT load bearing like coil spring or McPherson strut cars. Taking measures to make them super strong is wasted effort.
 
not even with something like this:

Forward-strut_A-body_sample.jpg
 
396 Signet said:
Mopar shock towers are NOT load bearing like coil spring or McPherson strut cars. Taking measures to make them super strong is wasted effort.
Click to expand...

there must be some load on them...what else could have caused the cracks on mine? think about it the shocks must impart some reversing load on the towers when driving.
 
340duster340 said:
there must be some load on them...what else could have caused the cracks on mine? think about it the shocks must impart some reversing load on the towers when driving.
Click to expand...

There is zero static loading on the shock towers. There are the damping loads during driving from the shocks but realistically you could drive 200k on potholed roads & they should survive unscathed. Not knowing the history of your car I can't comment. Is the car a rust bucket? Northern cars in the rust belt could have all manor of failures. Torsion bar mounts, spring mounts & frame rust outs sent most early A's around here to the boneyards in 1970's. That being PA, a salt zone where they have state inspections. Note the shock towers are virtually unprotected & will suffer max abuse from the weather and corrosion.
 
They can have some static loading from gas charged dampers. It's not much, but it's there.
The dynamic loads can be quite high. The damper's job is to take sharp, spiky suspension inputs and spread them out over a longer time span. That can result in some very high dynamic loads being applied to the shock mounts.
 
Fab work is nice, but I hope that cross tube btwn the plates is for a Monte Carlo bar. Take a piece of string and pull it tight btwn two anchors. Now take another piece of string and tie one end to the first string and then pull it tight too and tie it to an anchor. Push on the second string with your finger. That's what will happen to the shown structure under damper loads as it is shown. Adding the Monte Carlo bar will be huge towards the damper loads not flexing the mounts and ultimately the chassis, but it should have more than one bolt at each end to be most effective.
 
Those box jobs look really good!

I may have to look into those when I investigate adding a rear K member mounted rack and pinion setup.
 
nerd racing said:
not even with something like this:

Click to expand...


What do you want to bet that car has a coilover suspension?

I don't think I have ever heard of a cracked mopar shock tower. Has anyone else?

Maybe on a race car with solid mounted shocks with real high rates, but not likely on a street car with rubber.

Not to mention the shocks have very little damping in compression (which is where the largest shocks would come from).

I'd bet you have a rust issue.
 
The plan for the next early A:
1) welded subframe connectors
2) front sway bar
3) heavier T-bars (.920 +)
4) heavy duty shocks (4)
5) welded / reinforced K frame
6) welded / reinforced LCAs
 
robertob said:
What do you want to bet that car has a coilover suspension?

I don't think I have ever heard of a cracked mopar shock tower. Has anyone else?

Maybe on a race car with solid mounted shocks with real high rates, but not likely on a street car with rubber.

Not to mention the shocks have very little damping in compression (which is where the largest shocks would come from).

I'd bet you have a rust issue.
Click to expand...
my 1965 has cracked shock towers. it has stock suspension. i do not know the history of the car but i do know it has very little rust...
 
You must log in or register to reply here.
-

Back
Top