Simplicity. No matter where you look, it’s part of our everyday lives. From the way we communicate with one another to the manner in which we upgrade antiquated automobiles to better coexist with modern mobiles, simplicity is everywhere. And while this straightforward way of doing things can oftentimes take the fun out of life, when it comes to updating the mechanical aspects of an old car, the easier it is on you, the quicker you can get your car on the road – and put the fun back in your life.
Personally, I don’t mind cutting, welding, and even fabricating, especially when someone else is doing it for me (operating a digital camera to document the process can be quite strenuous on the index finger you know). But ultimately, I have zero patience, so the faster I can accomplish whatever it takes to drive whatever it is I’m working on, the better. That’s precisely how I ended up going “bolt-in” when it came to retrofitting my ’47 Chevy chassis with modern componentry. Above and beyond the entry-level skill factor, I also had to consider the original design of the ’37-48 Chevy frames – their two-piece (top hat) style construction doesn’t lend itself to being welded on too well. The top of the hat’s a bit on the thin side, but the lower plate it’s riveted to – the brim of the hat, as it were – is plenty beefy, making it ideal to bolt new crossmembers onto without worry of structural failure.
Kimbridge Enterprises in Snohomish, Washington, manufactures pretty much everything you need in the way of bolt-in parts and accessories for ’37-57 Chevy passenger cars and ’47-55 pickup frames (as well as ’47-55 complete chassis). For those who may not be familiar with the name, but recognize the product, Kimbridge has been manufacturing these parts for years, so they’re no newcomer to the frame components game. You can rest assured that every single part listed in their catalog has long ago been thoroughly tested for both fit and function.
For the Fleetline’s chassis, I went with Kimbridge’s bolt-in IRS kit, adjustable bolt-in K-member, bolt-in brake pedal/master cylinder kit (with mini booster), and bolt-in engine mounts, which I ended up welding in later on. Probably the most labor-intensive aspect would up being the removal of the stock K-member – or to be more precise, popping out all those stubborn factory rivets holding it in place. Otherwise, the stock frontend simply unbolted as a complete unit (and was easily rolled out from under the frame with the wheels still on) and the brake pedal bracket went in with nary an issue. Ultimately, I wound up swapping the Mustang II lower control arms and strut rods for a set of RideTech tubular lowers, which required welding a gusseted tube to the crossmember. My goal was to use ShockWaves front and rear – it’s a chore trying to outfit the stock Mustang II lower with a basic airbag mount alone, not to mention working around the strut rod in attempt to find a suitable location for a shock absorber. But despite my after-the-fact modifications, my frontend remains a bolt-in unit, just as it was intended.
1 – No offense to the restoration buffs out there, but this Chevy’s OE suspension, brakes, and steering were about as desirable as the rust that had taken a severe toll on the body. And as with the corroded sheetmeteal – not to mention that 216 with a connecting rod hanging out the bock – these parts have to go.
2 – Obviously, any major chassis work is better accomplished with as much of the car removed from the foundation as possible – if it’s possible to begin with. But if that’s not feasible, plan on spending twice as much labor time, namely with the K-member swap and brake kit (a bolt-in IFS shouldn’t require more than the removal of the front sheetmetal clip).
3 – The stock suspension did have one positive attribute – it unbolts as a complete unit, making it a breeze to remove. After a good soaking with some strong penetrating lube…
4 – …the frontend can literally be rolled out from under the chassis (supported on jackstands) once all the fastening hardware and brake lines have been removed and steering disconnected.
5 – We’ve more than covered our Mustang II install quota in recent months, so we’ll spare further repetitiveness. However, the stock frontend was removed and the Kimbridge three-piece crossmember kit was bolted up in order to keep the framerails square for the K-member installation.
6 – List the front suspension, the factory K-member can be removed in one piece, but requires more effort, as it’s riveted to the frame. Prior to attacking the little metal mushrooms, the brake pedal return spring bracket is cut off with a reciprocating saw.
7 – Now the tedious rivet removal session can begin. There are various ways in which to do this – I usually go about it with a three-part process, which starts with grinding the tops of the rivets flush with the lip of the framerail
8 – Next, the remaining shank is hole-punched and drilled about halfway through with a bit roughly three-quarters its size.
9 – The final step is using a sledge hammer and a punch to pop the rivets out. Using an undersized drill bit will not only ensure the hole remains smaller, but will allow the shank of the rivet to collapse when the punch (also slightly undersized) is driven in.
10 – Regardless of how the stock K-member is removed, the goal is to ensure no damage is caused to the frame – especially the sandwiched flange area where the new one will bolt up – during the process.
11 – Speaking of new parts, here’s what will replace the old unit: Kimbridge Enterprises’ ’41-48 Chevy bolt-in adjustable K-member kit. This particular one is designed for Turbo 350 transmission applications – they also offer a kit for TH400/700-R4s.
12 & 13 – Frames will vary a bit, and there may be some drilling required. Here, the rearmost holes on the vertical bar don’t line up with any existing ones – I simply drilled new holes from beneath with the bar in place.
14 & 15 – The triangulated bars bolted up with no problem at all. Now, not only is there less mass with old, bulky crossmember out of the equation…
16 – …the Gearstar Level 2 TH350 automatic has a suitable place to sit. At this point, the motor mounts had been welded on so that I could trial fit the trans with a bare block attached. Fits like a glove.
17 & 18 – With the K-member installed, the bolt-in brake kit is next. Unlike the factory setup it’s replacing, the bracket attaches to the framerail rather than the crossmember. A template for locating and drilling the holes is provided with the kit.
19 & 20 – After the holes were punched through the template and the inner framerail drilled accordingly, a protractor was used to transfer the holes to the outer ‘rail (rather than drill straight through).
21 – The bracket simply bolts up as shown. The rear portion will sit higher than the top of the framerail, but the front should be level.
22 – Assembly of the brake components – dual master, booster, pedal, and pushrod – is just as simple and straightforward as mounting the bracket. Because the M/C no onger lines up with the stock floor access hole (on the ’47, it would have to be under the seat), you may want to consider a remote-fill reservoir, such as the one Classic Performance Products offers.
23 – As previously mentioned, a Mustang II frontend in “stock” form is not easily modified to accept ShockWaves. Airbags can be installed without too much work, but finding a suitable location to externally mount a shock is tough, mainly because of the strut rod.
24 – Rather than trying to work around the Mustang II obstacles, the decision was made to eliminate them altogether – this translated into swapping the control arms for a set of RideTech’s tubular uppers and lowers (along with a strut rod eliminator kit).
25 – Proper gusseting will go a long way toward avoiding any structural failures, which is something you seriously want to avoid at all costs. RideTEch’s strut rod eliminator kit is fairly simple to incorporate, but it’s definitely no bolt-on procedure.
26 – With the pivot bolt aligning the two steel tube spacers, everything was tack-welded in place. To keep the spacers from moving around during welding, the bolt was kept in place and periodically slid back and forth.
27 & 28 – Not the pretties welds, but plenty strong. To add a little more insurance, the open end of the crossmember will be plated in later on. Remember, it’s not so much the suspension that puts the most stress on the frame, it’s the braking – and the lower control arm takes the brunt of that load.
29 – The Kimbridge crossmember hats are designed to accept pin-style upper shock mounts, which RideTech offers in all its lines of ShockWaves, including the Master Serious SKW100s, shown here. Also available now are internal ride height sensors, which eliminate the need for the lever style sensors that mount to the frame/control arm.
30 – The SKW1000s feature adjustable shock absorbers (single and dual options) and dual-convoluted airbags. If you’re looking to spend a little less, but still want the benefits of a ShockWave consider RideTech’s new Black Series (which Kev Elliott recently installed on his ’49).