Front suspension options
You're gonna have to alter the rack as well or find a shorter one.
Had already figured that as I mentioned many times already.
There's a reason no one has put a Crown Vic front end in an A-body. Yes, the swap has been around for awhile with hot rods and trucks. Typically, those applications all leave the Crown Vic suspension cradle intact. The reason for that is the crown vic cradle is aluminum. Cast aluminum. Sectioning and narrowing it is not something that the home welder should take on. Yes, it can be done, there are places that repair cast aluminum rims and motorcycle frames. But it's not an "enthusiast" level project. You should enlist an expert welder for that. As someone that has successfully TIG welded cast aluminum before, I wouldn't want to make that particular modification because of the loads involved. Obviously there's a first time for everything, but the Crown Vic suspension cradle swap has been around for a pretty long time. Long enough that guys like Denny and Gerst would have definitely had that option available to them. It wouldn't be a bad business model to take Crown Vic cradles, modify them, and sell them for use on Mopars. It would be a pretty simple gig once you had the jig set up and a welder that wanted to do it. And yet, multiple different company's have instead chosen to completely fabricate their own suspension.
Like I said earlier, it has been done successfully before. As for welding it, of course I would have a pro do it as I have zero TIG experience. As for why I believe Gerst and Denny wouldn't even consider the Crown Vic cradle is the fact there is no way to make it a bolt in deal without some pretty significant alterations to the A-body chassis. I mean, seriously, how many of you would cut their A-bodys frame and inner fenders along with welding in the necessary reinforcements?
Narrowing the track width will effect how the suspension handles. By narrowing the track you're decreasing the suspensions roll stability, you'll get more weight transfer during cornering. That will require stiffer springs and larger roll bars than a standard set up. The geometry remains pretty much intact, but it won't handle exactly the same as an unmodified set up.
Track width would be narrowed down to match the stock A-body spec. That's 1.9" per side (3.8" total). While it would have less roll stability than a stock width CF suspension, can you say it would be less than the Mopar suspension it would be replacing? Stiffer springs shouldn't be a problem. I think the stock springs would at least get it in the ball park considering they're meant for a 4000+ lb CV and not a 3000-3500 lb A-body.
And again, you're adding a crossmember that loads all of the suspension forces into the chassis vertically, just like the coilover conversions currently out there. The Mopar unibody chassis was not intended to be loaded that way, it carries all of its suspension loads horizontally in the K frame and torsion bar crossmember. There's very little vertical stiffness in the front end, even cars with the stock torsion bar set up have a ton of flex in the front. You would still need to significantly stiffen the front end of the car to run the Crown Vic suspension. And, how much better are the suspension numbers for the Crown Vic? Does it have better camber gain or less bump steer than a properly set up torsion bar system? Or is it just another way to convert to a rack and coilovers? Stock Crown Vic brakes are only 12", you can bolt on a set of 11.75" rotors using 73+ A or FMJ spindles and a set of the larger caliper brackets, which Dr. Diff sells for $90. If you go bigger, then you're buying an aftermarket brake kit anyway. Yeah maybe the Crown Vic aftermarket kits are a little cheaper, but you have to completely change over the suspension with significant custom modifications to even make it possible.
I'm not seeing how the load changes that much from horizontal to vertical. With the same spring rates (torsion vs coil), and the same fulcrum point, and plane of motion, the front end should see the same loads as long as the coil spring is not being directly supported by the inner fender itself. The CV suspension loads everything right on the frame rail and not the inner fenders. I really would like to see some actual mathematical calculations that show there is a difference. Regardless, I was already planning to stiffen the entire chassis no matter what suspension I run so I guess it's a moot point.
The big advantage to the CV brakes (and the rest of the front end) is that I can literally go to any auto parts store and find replacement parts in stock locally. In addition, there are quite a few more rotor and pad options available for it over anything Mopar. BTW, I already have SSBC disc conversion for it but the replacement parts for it cannot be sourced locally at all. Remember, this would be a daily driver so parts availability is a concern.
By the time you buy the crown vic suspension, modify the cradle, modify the A-body chassis to accept the crown vic cradle, re-work the steering column, sort out what to do for a steering rack, fabricate new engine mounts, figure out what fits for headers and oil pans (or if you'll have to go custom), and get the thing generally sorted you'll have at least as much money into it as properly setting up a torsion bar system, or buying an HDK or GST set up. Not to mention the time it will take to do all of that. Even if you did all the work yourself and came upon the Crown Vic suspension for super cheap I don't think you'd end up money ahead.
Already have a properly setup torsion bar suspension with heavier bars, rebuilt front end, Addco 1-1/8" sway bar, and SSBC disc conversion. It could be better but it is decent.
Now, for the cost side, there is no way it would cost anywhere near $3000 or more. That's just ridiculous to even think it would be near the cost of a HDK or Gerst setup. I can see that you're doing your best to discourage me from this path. That's cool. Never said I was going this way. It was just something I was spitballing and is purely academic at this point. While I do think the CV suspension does fit the bill in some respects, a lot more research in to it would be necessary before I would actually move forward with it. I was really hoping this thread would enlighten me to some other possibilities. I guess there really isn't any unless I come up with something on my own.
I like the tubular k-members a lot, and will probably go that route one day. But I don't see any reason to completely convert the front end. I have Dougs headers that took a little massaging to give me more clearance, am running a mini starter, shorty oil filter, and ujoint steering coupler, and feel fine with everything. Eventually I will go the tubular aarm route, but am not sure why you feel the need to do so much for such small issues.
More power too you, but reinventing the wheel is rarely pragmatic.
Eh, just would like things to be better. That's all. What's wrong with that? If the stock suspension was so great people like Denny, Gerst, etc. wouldn't be in business selling complete upgrades for it now would they? Lastly, I just like to think outside the box and of other possibilities. There is no harm in that!
