Help is just a click away!
Click here to chat with a Speedway Team Member
💬
Online - Chat with us!
Chat
Products to Compare (max of 3)
X
Compare These Parts
Talk to the Experts. Call 800.979.0122, 7am-10pm, everyday.
Customer Service
Since 1952
in
in
Talk to the Experts. Call 800.979.0122
Shop By
Support
Account
Street Race Truck More... The Toolbox

Sedan Delivery Coilover Conversion

12/12/2016
Elmer gets an altitude adjustment

Last time you met our ’46 Ford, Elmer. I also made the embarrassing confession that Elmer still rides on a Corvair IFS. In fact, he’s rocking it like it’s 1976 all over again. (Play Free Bird!)

Part of the reason those frontends fell out of vogue with the introduction of the Mustang II IFS was the availability of decent rebuild and hard parts for the older, less popular Corvair cars. (We won’t even talk about the Corvair’s eccentrics or the camber issues inherent with the design. Oops guess I just did!)

With my commitment to stick to the meat and potatoes of how this truck was built years ago, I’ve made the choice to retain the Corvair IFS. After all, since rebuilding it, I’m already into that outmoded technology up to the ankles with both feet. Might as well stay there. Last time, I went over the rebuild of that frontend and steering setup. Those parts have served very well over the last few years of driving. They took us to California and back in ’14 and many, many miles since then.

Thanks winter! Gosh.

That is until we were headed out to a rod run in Wayland, Missouri early last spring. That’s when we encountered a giant, unavoidable pothole passing through Omaha. I guess street crews hadn’t gotten to yet. Or they’d lost too much equipment in an effort to satiate it and had written it off. At any rate, it was a bone shaker. One that reminded me all about 50 year old spring steel, metal fatigue and stress risers.

My left front coil spring broke. Right along an old grinder nick in the wire where the coils had been cut years ago.

Bummer dude...

However, with the way the spring broke and knowing the suspension as well as I do, I was able to do a roadside alignment change and motor on for our weekend commitment at the show. (Dig the road rash on the lower control arm and compare the last article. Drive ‘em!)

We weren’t even home yet when I came to the realization that I was NOT going to pay the going rate for a new pair of Corvair springs. Not gonna happen. Especially when I’m going to lop 2 coils off of them to match the setup on the car anyway.

What I did recall was the similarity of design and geometry between a stock MII and my modified Corviar. Back to the parts counter. . .

Just as I suspected, I can make that work. Plus add a nice upgrade to adjustable height and selection of spring rate.

The main difference between the two spring designs is that one top is a tangential tail and the other a squared end. It’s pretty tough to go from a tangential to square but vice-versa is a snap. Well, a cut-off wheel anyway. (Note: Do not EVER cut a square-end spring that is to be retained in the square end spring pocket. If the pocket is designed to make full contact with the spring it must remain that way.)

Side-by-side you can see the matchup is pretty decent

If you must cut a spring don’t ever, ever use heat. A cutoff wheel makes quick work of the material without generating excess heat that will ruin the spring. You also must note that when you shorten a coil spring, the stiffness of the spring also increases resulting in a stiffer less forgiving ride. That said, I’ll show you how I repurposed these MII springs to work in my Corvair setup.

I made my cut at the very end of the flattened surface of the square end. This allowed the new spring to mimic the original perfectly. Remember don’t nick the next coil in line when you cut. That’s where all this extravaganza started. Don’t make a new stress riser in your spring.

My installation was a little different than the instructions indicate for a MII setup. In addition to needing to install the supplied 7/16” ID tube in the lower shock mount to accommodate my smaller lower bolt, I also had to install the spring in the pocket and work the shock into the sleeve as I fed it into the spring. Time consuming but all in all, not too bad.

Something else to note here. Splurge on the Torrington bearing that goes under the spring. I actually took this all back apart to install them. While you’re there also treat yourself to the heavy coil-over adjuster wrenches as well. Money very well spent.

Something to keep in mind. Springs settle. Sometimes they settle a lot. Overnight. It took me about a week of fiddling around and adjusting to arrive at where I wanted to be concerning ride height.

Oops, cranked ‘em down too far. Looks cool, won’t turn.

I used the 375lb springs at full low as my starting point and they ended up being just about right for my application. That is, after I adjusted them up about 2/3 of the way up the adjuster sleeves. My engine sits a bit farther back than some and I prefer a soft ride and low stance. Your preferences may require a different rate or some experimentation.

Until next time, thanks for reading!

Products Featured in this Article

Related Articles

Special Delivery
by Jeff Karls - Posted in Tech
1/26/2018
Ride along as you read the story of how "Looney Tunes" started and made its way back to the original owner after nearly three decades.
1946 Ford Sedan Delivery Engine Detail
by Jeff Karls - Posted in Tech
5/18/2017
Speedway Motors Product Manager Jeff K. talks about how to really make your engine bay stand out from the crowd with just a little patience, and some Speedway products.
’40 Style 15” Steering Wheel
by Jeff Karls - Posted in Tech
5/16/2017
Speedway Motors employee Jeff K. has hand his hands on a lot of projects through the years. Check out his how-to on the repaint of the steering wheel on his '46 Ford Sedan Delivery.
Restyling a Mullins Trailer
by Jeff Karls - Posted in Tech
2/7/2017
Speedway Motors Product Manager Jeff K. not only has an awesome 1946 Ford Sedan Delivery, he has a Mullins trailer that he restyled to match "Elmer". Jeff took the time to write up what he went through to make the style of the Mullins match up better.
Sedan Delivery Floor Insulation
by Jeff Karls - Posted in Tech
12/12/2016
Jeff K. talks about the keeping his cool in his '46 Sedan Delivery, with a little help from insulation and damping material.
Sedan Delivery Steering Update
by Jeff Karls - Posted in Tech
12/9/2016
Speedway product guru Jeff K. wants to introduce you to another of his projects, "Elmer". There's a long history with Jeff and this vehicle, best told by Jeff himself.
Disc Brake Conversion
by Tyler Wesely - Posted in Tech
5/24/2019
How to change brake pads, rotors and calipers using the Mustang II complete brake kit. Replace your drum brakes with disc brakes for performance and better braking ride. For use on Bobcat and Mustang II spindles.
How to Build 4-Link Bars
by Speedway Tech Team - Posted in Tech
5/9/2019
Do you have a project that will require you to build your own 4-link bars? Here's a demonstration on how to determine the bar length, weld the parts and assemble the links using steel tube ends weld bungs and forged 4-bar rod ends.
Upgrading Your Air Cleaner Assembly
5/9/2019
Learn the proper steps in upgrading your air cleaner assembly to ensure clean air, allowing your engine to more easily make the power that it should.
Take a Kid to a Car Show
by Jeff Karls - Posted in Street Rod
5/7/2019
What is it like growing up going to car shows? This story explains how attending car shows is a way of life and how the tradition is passed on from generation to generation.
Suggestions
Error
X
Note
X
Ok