Anybody done a coilover conversion

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68Runner
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Anybody done a coilover conversion

Post by 68Runner »

Just wondering if any body on here has done this with any success. Considering trying it on my 68 Satellite

Did a coilover conversion on 56 F100 and it turned out really well.

Just wondered if the inner wings will take the pounding from the weight of the vehicle.
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Pete
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Post by Pete »

In my opinion the car's front end is NOT strong enough to take the load, this is why the Reilly Motorsport Alterkation has a complete cradle for its coil over arrangement. There are whole host of issues to resolve such as bump steer, ackermann angles. Apart from header clearance I am not sure what you will gain.
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68Runner
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Post by 68Runner »

I looked on the Magnum Force website and it shows the shock mounting through the same hole.

Why would this have anything to do with header clearance or any other problems you mention. You'd only remove the torsion bar and replace the shock for a 1.9" coilover.

My reasoning is that it gets rid of the torsion bar setup for a more adjustable suspension
Could also change the rear for ladder bars and coilovers plus a panhard rod
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Post by Blue »

You need to brace the shock towers, magnum force among others sell a kit to do it, there is no great weight saving. You would also need to somehow support the rear of the lower control arm, the torsion bar does that as well.
Fitting a rack will lead to making a new K frame to get it in the right position. There is also the steering arms to consider, just swapping them side to side so they point to the front will not do it, that will cock up the Ackermann and is not safe although it has been done that way by many people for strip only use.
As Pete says, oil pan and header clearance is about the only thing you gain going that route. Only a full on strut front end would save weight as well.
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Post by 68Runner »

Blue wrote:You need to brace the shock towers, magnum force among others sell a kit to do it, there is no great weight saving. You would also need to somehow support the rear of the lower control arm, the torsion bar does that as well.
Fitting a rack will lead to making a new K frame to get it in the right position. There is also the steering arms to consider, just swapping them side to side so they point to the front will not do it, that will cock up the Ackermann and is not safe although it has been done that way by many people for strip only use.
As Pete says, oil pan and header clearance is about the only thing you gain going that route. Only a full on strut front end would save weight as well.
I haven't said anything about a steering rack change,header change or weight saving. I'm on about taking out the standard shock and replacing it with a coilover unit.
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Post by latil »

So,you have to brace the shock mount because the coilover increases loads considerably.
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Post by Blue »

No you didn't, but those are the reasons why it's normally done.
The inner wing is not designed to carry the weight of the vehicle, so without bracing it will flex and eventually fail. The other problem with coil overs mounted like that is at the length they need to be to fit in the space, they will be too short to retain full suspension travel, which may or may not be a problem depending on what you are expecting to do with the vehicle, I'm guessing it's not a handling application if you are talking about ladder bars.
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Post by 68Runner »

It was just a thought that's all. Having done the conversion on my truck, I just thought it would be a decent upgrade on the original setup
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Post by Blue »

Fair enough, I can see changing what I assume was a leaf sprung axle on the truck to a coil over set up would have it's benefits.
I was just looking at that Magnum force kit, by the time you'd added the tubular upper arms you need to clear the springs you're talking a $1000 modification there.
You should be able to do whatever you want with the standard set up, it already has ride height adjustment built in, you can get different diameter torsion bars to get your disired Spring rate and the worlds your lobster when it comes to shocks.
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Post by 68Runner »

On the truck I converted the jag clip to coilovers and did a 4 link on the rear. It handled really well.

Had no dealings with the suspension on these cars and was just thinking of things while I was replacing tired and worn out crap. For some reason the front crossmember is about 3" off the ground so I'm replacing all the ball joints and bushes.
I want to get it driving and handling pretty good before it goes down the strip at the Nats next year
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Post by Pete »

For a cheap front end set up the Chrysler one works pretty well as long as all the components are in good condition.

In the film "Bullitt" the Charger was rock stock apart from re-enforcing plates welded underneath the LCA's to brace them and nothing failed throughout all the filming.

The only thing they suffer from (apart from big header clearance) is a lack of caster for straight line stability. This can be mitigated with offset UCA bushes on the cheap or more expensively Adjustable UCA's based on Heim joints.

Most advertised kits don't really deliver on all aspects (regardless of what they actually say in their sales pitch) and are an expensive exercise.

In many respects, I believe that making lots of changes could potentially devalue your car as most prospective buyers want standard cars. There are a lot of really nice but non-standard cars for sale at the moment.

I have a 5 link rear car that has a solid axle, with adjustable front UCA's if you want to see what is involved.

I do not live that far from you. Just a thought.

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Post by MilesnMiles »

Hotchkiss have made these cars handle whilst maintaining the stock approach.
I'm looking at firm feel
Tubular UCAS for better handing
Bigger torsion bars
Potential for their steering box which has received acclaim for much tighter steering but is mucho dollars.
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Post by Mick70RR »

68Runner wrote: For some reason the front crossmember is about 3" off the ground so I'm replacing all the ball joints and bushes.
Adjust the torsion bars then and raise the front up.
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Post by Dave999 »

the standard setup puts the centre of mass in relation to suspension, backwards and in the middle of the car, as low as possible. This was a good move. same setup employed in many an open wheel racing car

the forces are all taken by the K frame and the central cross member so flexing of the chassis in cornering is reduced to just that of the monocoque. you won't ever cause the bonnet to pop open due to inner wing flex on a mopar.

to make it handle better you need full suspension travel,
fatter torsion bars chosen based on the weight of each corner

and then a set of shocks Valved appropriately for the spring rate of the torsion bars and the mass they have to carry.

the originals were designed/sized for 1960s American roads and 1960s American driving and a 1960s viewpoint that driving the car should be easy if you were a 90 year old granny.

basically a spring is a spring doesn't really matter if its a coil or a bar.
all springs take a "set" and age and sag, at least with a torsion bar you can just wind the car back up. The sag should not have reduced the spring rate by any margin really. for that to happen the spring would have had to have been forced past its limit of elasticity (i.e bent and fatigued) or abused with a blow torch

some of the stuff available is only good for going in a straight line, race only.
there are no welds apart from the chassis mounts in your current front end set up. its all pressed and folded steel and forged parts so that should the worst happen it will bend and buckle but it won't snap. its the automotive suspension and steering version of a Weeble...beat it and beat it but it won't fall down

Morgan and Roger have both found solutions to modernising the handling of their chargers.

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Post by Dave999 »

Mick70RR wrote:
68Runner wrote: For some reason the front crossmember is about 3" off the ground so I'm replacing all the ball joints and bushes.
Adjust the torsion bars then and raise the front up.

if you replace the upper and lower arm bushes

DON'T do up the bolts (Kframe pins and cam bolts) for either until the car is resting on its wheels

If you do them up with the suspension at full travel, as you lower the car you rip the guts out of the bushes straight away.

get the height right
do up the strut rods
do up the lower K frame pins
do the alignment (wheels on the ground)
and do up the upper arm cam bolts.

that way the bushes are not under any torsion when the car is at rest.

uppers wear out quicker due to shorter arm therefore wider arc, and its a smaller bush.
but lowers are much harder to change so they get left, they make it handle really badly you will also have noises and or clonking. you can see if they are bad as the rubbers of the bush can start to come out .

mine are shot at the mo. to the point where I'd be embarrassed to let anyone else drive.... hence the long post...i've been reading up.

apologies if I'm teaching you to suck eggs

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