The mustang stuff isn't frowned upon .. Just the cheap stuff. Stick with Heidts, fat man, or Morrison and all will be fine. They have engineered the hell out of it. I actually rode in a crown Vic swap the other day and it rode really good. No tire issues with his but it's in a later model than what we drive. But it was nice. Bought the whole front end here in phx. Pressure washed and pulled for 450. Can barely buy a good crossmember for that.. But even though the frames seem to be close to our trucks , it's the width of the inside of the fenders that limits it's use. If you want to stick with the offset wheel like the mustang they will work. But that's why there are so many options out there.

 

AX, that was the first time I ever heard anyone say what I always wondered about. So much time and money, and for what advantage?

 

I think it depends on what you expect out of the vehicle. Decent brakes? Power steering? Some lowering? Better ride? Better handling? Swapping to an ifs of some kind addresses nearly every one of these issues. It's no mistake that manufacturers use ifs pretty much exclusively on passenger vehicles today. Cut and pasted:

Improved Steering, Handling and Braking

• In a rigid suspension, if one wheel jogs or bounces, the entire axle tilts, causing the opposing wheel to tip in or out at the top, no longer rolling straight ahead, an effect called "bump steer". Rigid axles are also less responsive on turns and vehicles carrying heavy loads are subject to instability called "shimmy", caused by forces translated across the axle from wheel to wheel. During hard braking, solid beam suspension can cause the front of the vehicle to nose dive and twist. Independent front suspension (IFS) corrects or vastly improves all of these effects by allowing wheels on the same axle to respond independently to driving conditions.
  
  

Ride Quality

• Ride quality is a concern that has evolved with our culture's increasing dependency on automobiles for recreational and commuter travel. Overall ride quality, or how comfortable a car feels to ride in or drive, is measured by a combination of factors, including noise and vibration, the translation of bumpy road surface to passengers, the smoothness of the car's steering and how well a car handles and corners. Independent front suspension solves some of these problems by de-coupling the front wheels, improving overall stability and creating isolation between the suspension and the vehicle chassis.
  
  

So for this project.....yes we want to use IFS. We need the brakes and the power steering anyhow. And will decent power and the desire for it to handle well and have good comfort.....the ifs seems like a good way to go. How to get there is the question. I want moderate drop, and don't want to be limited to OEM wheels. The more straight forward the swap, the faster it will happen and the cleaner it will likely look.
The advice is great and greatly appreciated! Keep it coming!

 

I can say at least from my experience, even with a new drop axle, all new hardware, Teflon lined springs, straight axle still can't ride or especially handle like a well set up ifs, and by the time you get done with everything you will have more money invested than an ifs. Trust me I know. That was the first way I was going to go. Cost actually exceeded that of my new front end, even after new rotors and a few new bushings.

 

I'd recommend the Jag or the Lexus for good geometry and matching front axle weight and tread width to fit under the fenders without needing funky reverse offset wheels of the CV. If you can find a complete donor car the IRS is also useable and desirable. The C5 Corvette is the sleeper donor. The original MII stuff was actually for the Pinto a lightweight front econobox local grocery getter with stamped sheet control arms, a single pivot lower with trailing arm, tiny brakes, and 4 lug hubs for 13" wheels. and narrow crossmember and tread width. Perfect for the equally lightweight pre 35 Fords that needed a narrow IFS with short control arms to hide under the clamshell fenders. The MII units were an improvement over the buggy spring and radius rods for rod run cruising popular in the 80s. When they started to be used on larger heavier vehicles the weaknesses reared up. The kit IFS altho still generically called MII type have nothing but possibly the spindle geometry and/or ball joints in common with the OEM parts. There are still some less than desirable suppliers selling a bare crossmember for the stock suspension parts. Avoid them like the plague unless you are building a Model A coupe.

 

As everything has been mentioned, all the reasons are out there on what will work and why, and why certain things don't. after much research, that's why I went with the Lexus. I am not the one pioneering this install . Check out lexcoe on this forum.. He's in Australia and has already done this. He's using the sc front end and the all alloy v-8 from the Lexus also. I was the lucky recipient of his crossmember he built for the trailing arms as it didn't work for the ride height he was looking for. It's going to be perfect for mine. He's got some great pictures to see what it will look like. Believe it or not the corvette front end can be had for a lot cheaper than you would think also and is available pretty readily. Ive seen several for around 600 complete. And there are installation kits made for them.

 

Wolf, That info is primarily based on the cross spring "buggy spring" front axle ford used on the pre 49 passenger cars. They are not valid for parallel leaf sprung beam axle setup used on our trucks. The springs act as sway bars when the axle rocks and it has automatic camber gain like a well designed IFS, and well designed drag link pivot placement so there is little to no bump steer.
Cdl,
Ride comfort depends much more on passenger seating location and seat construction, vibration and road shock isolation, spring rate and shock valving, as well as tire type and construction than suspension design. The OEM ladder frame was designed to twist and flex quite a lot, one of the reasons they have lasted so long without getting destroyed on the poor roads and cross field driving they endured in the 50s, The passenger compartment was placed over the center of oscillation or rock, and the cab was isolated from the frame and road shock with large rubber isolators. Add recirculating ball power steering box, modern solid engineered foam cushioned seats, softened springs with matching shocks, flexible sidewall 4 ply radial passenger car tires of adequate size, lightweight wheels, and it definitely will ride very comfortably and smoothly. Installing an IFS requires stiffening the frame with boxing which removes much of the IFS ride comfort. If you use original type steel spring bench seat, 6 ply truck tires, or bias ply tires, heavy wheels, off the shelf generic shocks, mismatched roll bar(s) with an IFS there is no way it will ride very comfortably.
Handling differences on our top heavy high roll center trucks is virtually a non issue, no one in their right mind is going road racing in a 50's era truck. Since I do race, I am very sensitive to handling and ride quality. I'll race my Solstice and tow it's trailer cross country comfortably with my beam axle panel. If I did want to maximize the handling I'd chop the top 5", section the body 6" and droop the nose 3" before worrying about the suspension type.

 

I wouldn't go as far as saying it will remove most of the ifs ride. I've been in plenty of ifs equipped trucks both ford and Chevy and they ride awesome. With all due respect I don't think someone looking to put an ifs in is worried about using heavy ply radials or worse bias ply tires on a modernized early truck. Even with most frames being modified by being boxed with extra cross members added, stiffening up the frame is what makes them handle so nice with no sacrifice in ride quality.

 

Check out charlieled on this forum . He can lend some insight to the. Corvette ifs install as he has done the C-4 on one of his trucks. He would be the one to ask. Might be something else to consider if we havnt all confused you enough as it is. As you have seen, there is an enormous amount of help and knowledge on this site. AX, charlieled, lexcoe and everyone else on here has contributed to a lot of my decisions. Ultimately it is your decision but I found it nice that everyone here was willing to share their trials and tribulations and ultimately help me make an informed decision. So hats off to all...

 

Wayne, If you go to Mid Fifty's web site, you can order or download their free catalog. There is a wealth of valuable information in it including a spreadsheet of how to lower the front suspension with the beam axle. Using reversed eye down and forward springs, in combination with 3" drop axle, you can lower the front approximately 6", that's low enough to knock over a standing beer can with the front bumper, as low or lower than most MII IFS kits without dropped spindles. The guy that does the best dropped axles can give you a 4" drop but that will give tie rod and oil pan clearance issues as well as bump steer. Mid Fifty says you can get two more inches of drop using monoleaf springs, but I'd highly discourage you from going that route.

 

I also agree with AX when it comes to mid 50's site. Since they are here in az, they have quite a bit of my money already, and I can attest to the knowledge there as to the stock front end if that's the way you go. I also have a 55 3/4 ton we are building as a shop truck and we left the stock front end in it, and used the down and forward springs along with the reversed eye for a moderate drop and also did the same I the back. Also adding the Toyota power steering kit made all the difference in driving compared to stock. Also added the sliders in between the leafs to ease the friction of metal on metal. Be prepared though the springs aren't cheap and the power steering kit was 539, and you still need a power steering pump. Good thing it was company credit card for all of those purchases...!

 

Oh and YES he's right stay away from mono leafs.. They sound good but not many that used them are happy with them..good advice AX...

 

You can do the Toy steering conversion for 1/2 the price of the complete kit depending how hard you scrounge for a used box. I paid 75.00 for mine, a number of others have found them for free to 100.00. Used boxes are fine to use, the recirculating ball design has practically no wear points in them. If you can fab you can make your own mount as well. I'd just buy the conversion pitman arm and U joint.

 

The corvette ifs is one I hadn't given much thought to. But now I am looking. It seems to put one right at the bottom of where my ideal ride height is. A little different with the wheel choices at that point, which may not be all bad. But I don't want different patterns front and back. Looks like some clearance issues to be careful of as well with the rack. The factory spring deal is a little funky at first glance as well.

I do think I am most interested in the Lexis, Jag or Corvette. Any disadvantages you guys can point out with each of these?

 

Disadvantages (and advantages) IMHO:
Lexus: New donor here in the states, requires fabricating your own mounting arm crossmember or buying one from Lexcoe (member here that has been documenting his install in Australia). Lexcoe does extremely clean work. He has not completed his install, so not all the details and potential issues have been identified. Donor vehicles were popular so low mileage donors are plentiful and inexpensive since swap has not yet "caught on". Aluminum crossmember reduces front weight is compact and complete with useable springs and sway bar.. Spec matchup is excellent. Bolt pattern is common GM.
Jag: Donor vehicles were not plentiful in the states, mostly popular with geriatric affluent females, so found in around cities. 2 versions, early with drum brakes late model with disk brakes. Both are high quality Girling design. Body was made of the ever popular in the 80s compressed rust, so most ended up as crusher fodder before their time. Small amount of crossmember trimming, plating required to install in 53-56 frame. Small amount of straight forward fab work (primarily upper shock mount, and front mounting arm spacer. One of two mounting choices must be made early in the install affecting the final ride height: use the elastomeric OEM mounts making it a near bolt-in, or remove mounts and weld in. Because of donor age, most need some rebuilding, but parts are readily available and equally priced to US manufactured vehicles. Assembly is complete with useable springs and swaybar. Good aftermarket support. Bolt pattern is GM. Good spec match.
Corvette: AFAIK Only one manufacturer offering crossmember. Only suspension parts are used on aftermarket crossmember, not complete unit. Not a lot of history with this swap. Donor parts may be difficult to find because of vehicle's continuing popularity. Springs need to be swapped for coilovers(?) Specs are fair match.