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Old 07-25-2009, 12:36 AM
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Quote:
Originally Posted by AntnyL
Not to sound like a jerk or anything, but if you're going through all this trouble, why install a 30+ year old suspension system? Have you considered a tubular a-arm independent kit instead? By the time you replace all the worn bushings, brakes, bearings, steering box rebuild, steering component replacements, etc., you might be $ ahead in the long run by going with a Mustang II crossmember (Fatman, TCI, Heidts, etc) and a-arm kit, and a modern rack-and-pinion steering system. It's easier to install than a clip, and, they are engineered to work with your specific vehicle. Clips are not. Just food for thought.


The Mustang II was built from 74-78, by my math that's about 30-35 years ago (same as camaro/nova clips) New wear parts on both systems is a given, but r&p steering was developed for use on small light cars as a weight and cost saving measure. M II is great on a small, lightweight rod ( Mustang II's were under 3000 lbs) but for a truck that carries about a ton on just the front wheels I'll stick with something beefier, thanks. Clips, especially the late 70's Camaro/Firebird/Nova are designed for bigger, heavier cars and include a large piece of that strong, fully boxed, -designed by real engineers and computers- frame. As for engineering, kits are "engineered" to fit as many different frames as they can so they can sell more, period. How many "kits" come with a swaybar standard? Wanna have some fun, unhook the swaybar on the front of your daily driver, then drive in a "spirited fashion" down your favourite piece of twisty road and see how it "handles" !! And lastly, easy to install. Lets see, drill out or grind rivets holding stock crossmember and original trans bellhousing mounts( for mid 50's chev p.u.) and remove crossmember and mounts, trim frame rails for boxing plates, grind to fit boxing plates or make your own (oh what fun without a plasma cutter), grind to fit and weld in crossmember after determining proper rake angle of frame ( better do this on a frame jig if you don't want to weld a permanent twist into your frame), determine proper anti-dive angle of upper hats, grind to fit and weld those on, weld on strut rod eliminators and gussets so you can use full lower tubular control arms (gotta look cool, might as well get the stainless ones-Oops $$$$ penalty). Now, let's see is the easier part over yet? Don't forget we'll have fab (grind to fit) and weld in some motor mounts, possibly notch the frame for rack clearance ( you do want it low don't you? ) Now you can trial fit the suspension pieces ( don't put the springs in yet, you'll do that in a later mock-up) and the rack and see if the geometry is even close (you'd be surprised) . Check for bump steer, fix as necessary ( you do know how to correct that don't you, you don't want your ride to weave like a drunken sailor) Whew, I'm getting tired just typing this !! And that's not the end of it....does the "kit" compensate for moving the wheels forward as you lower the vehicle so it looks "right" (seen that boo-boo lots) and if so how much? With everything welded in place "as it fits" can your local shop get it aligned correctly or are you going to try to get it aligned with everything tacked in place during one of the many mock-ups you'll need to do, where's the ride height going to end up? Do you need drop spindles or not, how do you figure it out, what springs do you need( your truck is heavier on the nose than a M II, imagine 2 or 3 people sitting on the hood of the mustang, how's it going to sit,ride, handle?)and so on, and so on....
Or you can take a bunch of careful measurements from a suitable complete donor car (height and width of frame from ground at various locations while sitting at ride height, spindle centerline in reference to fixed location on frame) and some more careful measurements from the recipient vehicle sitting at it's planned ride height ( height and width of frame, location of rad support mounts in 3 planes in relation to the ground and a fixed point on the frame rearward of the graft, spindle centerline). Then cut both frames, grind to fit, and weld in place (the last two you will remember from the "kit") Modify the front of frame to allow mounting of the front sheetmetal, assemble new and refurb'ed suspension pieces and you're done, THE ENGINEERING'S ALREADY DONE ! You KNOW it will steer right because it's not "based on" a factory engineered steering system, IT IS ONE !!

I think at least in part the widespread use of the M II kits on bigger hot rods is due to the huge amount of ads and coverage these thing get in car rags, which is kinda self-perpetuating, you see. Also the myth that they are simple, safe and easy to install is a strong lure for lots of people. Now when was the last time you saw someone advertising clip installs in a mag, I did see one guy on Epay but that's about it.

At least, that's my not so humble opinion, of course anyone is free to do as they choose.For what it's worth, the truck in my avatar has an 85 Pontiac Grand Prix clip, done by me, and it rode,stopped and handled great. I've had experience with both, can you guess which one I'll be using on my next project ? I'll give you a hint, they used basically the same suspension from 1964 to 1988 because it worked great ! -and no it's not a Ford

Autobuff, if your truck is a 3/4 ton longbox, a late 70's camaro clip, PROPERLY DONE, will work great and cost less than a Mustang II kit if you can get the clip and the welding done for a reasonable deal. My 4 cents worth (gawd I ramble on sometimes... )

Last edited by bobinbc; 07-25-2009 at 11:15 AM.
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