Project 1974 Chevy K5 Blazer - 4Wheel & Off-Road Magazine

1974 Chevy K5 Blazer Passsenger Side View

It was time for me to start another project. It had to be a '73-'75 Blazer for the full convertability and all-around great wheelbase, plus it was the first 4x4 I had ever owned. I had been planning on how I would build another one since I sold my original 10 yearsago, and my plan called for a crossover off-roader like nothing we have really tried before.

It couldn't be too expensive because I wasn't going to keep much of what was probably already on it. And I didn't want to be doing a restoration so it had to be pretty much rust-free. I basically needed a clean body and a frame.

Two months had passed and I had somehow bought two more trucks, neither of which would be my ultimate premudder-a cross between a prerummer and a mud truck. In desperation to get a foundation for Fabworx Off Road to start on, I accidentally found and bought the biggest Blazer pile in the world, in the middle of the night, ignoring all of my own rules about buying vehicles. I barely even turned the flashlight on before I offered the guy half of what he was asking, and later realized I had still gotten taken for a ride. It had tons of rust, it'd been rolled, it had been parted out and put back together with junk, and once we took the engine apart we would find out that the No. 1 piston had a hole in it. Awesome. I'm glad I bought such a gem to start with.

Brian McCully was such a nice happy guy when I first met him and the rest of the Fabworx crew. We'll see how much he's smiling at the end of the buildup. He and Jack Arrington were actually in the middle of pulling the entire front end off the body when I snapped this. Since the engine was going to be coming out and we had some special plans for a '98 front end on this K5, it made sense to just pull the sheetmetal before we started.

Brian McCully was such a nice happy guy when I first met him and the rest of the Fabworx c

Two days later I had it at Fabworx's shop, and after the verbal berating I received for the quality piece of machinery I had bought, we were looking at the task ahead realizing that there was no real room for error with only seven weeks left to build the truck. The first thing to do was to attack the frame, fixing the horrendous cracks and shoddy repairs that occurred over the years, and get some suspension on it to hang the axles from. The next part of the plan was to pull the big-block 396ci and give it an Edelbrock spice-up while we fit the tranny, transfer case, and axles underneath it. Without a working powertrain, this truck wasn't going to go anywhere, and we were about to find out that the short block was worthless.

Yes, intentions had been good; this would be a fun thing for everyone, and we would have plenty of time to complete it. But the deeper we dug, the more work we found, and what was to be a somewhat economical and leisurely build got mighty expensive toward the end, just hours before the Ultimate Adventure started.

I think you'll like what we ended up with. The K5 (in the end) turned out to be a prerunner-themed 4x4 with mud-truck roots: It can roar 80 mph down the highway, churn big Boggers through thick mud, and hit desert whoops at 60 mph. But that's a ways off from where we are today.

I knew the steering box and frame had issues just from the testdrive, but that was a normal occurrence and I was expecting it on any '73-'87 Chevy. What I didn't realize is how bad it could actually be, and what some people would call a suitable fix. Once I actually got under to examine the frame, I was enlightened on what hackwork really was. Real hackwork is doing things like welding the power-steering box itself to the frame of the vehicle.
I knew the steering box and frame had issues just from the testdrive, but that was a norma
None of us had ever seen a Chevy frame this bad. In hindsight, we should have cut the front end off and made our own framerails. After hours of grinding off junk and cleaning multiple frame cracks, Tim Fenzel finally could put all these weld repairs in. It looks like some kind of Hobart Welder ad, doesn't it?
None of us had ever seen a Chevy frame this bad. In hindsight, we should have cut the fron
With the frame welded up, Arrington and Tim Fenzel were able to get started on the frame bracing. Since it was already too far gone to just use an Off Road Design steering-box brace, they had to plate the frame on both sides with 3/8-inch steel. Once installed, we would be able to put our donor steering box on and move to our donor axle and crossover steering.
With the frame welded up, Arrington and Tim Fenzel were able to get started on the frame b

Last year's yellow Ultimate Adventure Chevy saw more beatings than any other U.A. vehicle to date. It was so wasted that there became a point where it was smarter to part it out to make multiple vehicles work rather than dumping a ton of money into it. Since this Blazer was being built with as much stuff as I could find already laying in my yard, it was lucky enough to be the recipient of the yellow U.A. Chevy's front Dynatrac Pro Rock 60, crossover steering, and Redneck ram. That front setup lasted through the extreme beating given to the yellow Chevy, and it would all swap straight onto my Blazer, even the leaf springs.
Last year's yellow Ultimate Adventure Chevy saw more beatings than any other U.A. vehicle
Arrington bored out the hole where the shackle hanger mounts to the frame. The rivets were knocked out of the factory ones, and they were ditched to make room for a new pair of Off Road Design heavy-duty shackle hangers with more durable urethane bushings and larger hardware. The new ORD shackle hangers bolt up to the frame without too much headache. The biggest issue is probably trying to get the rivets out of the stock ones and off the frame. Usually I would've just used ORD's shackles, but since I somehow left those off the order sheet, Fabworx quickly made up almost identical shackles to hang our springs from.
Arrington bored out the hole where the shackle hanger mounts to the frame. The rivets were
The '73-'87 Chevys have a clearance issue with crossover steering and the factory frame crossmember below the engine. Since this K5 was going to be getting the crossover steering from last year's UA truck, and we had pulled out the engine, Arrington knocked out the factory crossmember to get this Off Road Design motor mount and custom tubular crossmember to fit in between the framerails. This will help us clear our steering, while still providing lots of structural support. The motor mount/crossmember package fixes the steering clearance issue while also providing beefy motor mounts to replace the worn-out factory ones.
The '73-'87 Chevys have a clearance issue with crossover steering and the factory frame cr

The crossmember and motor mounts attach much the same as the factory one would. If you have an opportunity to remove the rivets while the engine is out of your frame, please do so as the extra room and visibility make it a much easier job than trying to suspend the engine from a cherry picker while you remove the motor mounts, and then try to replant it.
The crossmember and motor mounts attach much the same as the factory one would. If you hav
I knew beforehand that I wanted this K5 to be motivated by a big-block, and I had thought it was a lucky coincidence I had found a K5 with a 396ci big-block. We were about to tear into the engine to try and weasel some serious horsepower out of the existing short-block using a trailer full of Edelbrock, Performance Distributors, and Flowmaster parts.
I knew beforehand that I wanted this K5 to be motivated by a big-block, and I had thought
The engine was already sitting on an engine stand, and the heads came off the 396ci big-block after twisting some crusty old bolts out of the heads. Arrington had already warned us that it wasn't a good idea to put all these high-performance parts that would generate more heat and pressure onto a tired old block. Well, Arrington had raised a very good point, and it was a decision I didn't even have the chance to make upon examination of the No. 1 piston. There was a good-sized hole right on the ring land of the piston.
The engine was already sitting on an engine stand, and the heads came off the 396ci big-bl

The Dynatrac front axle was already complete and proven off road, but we needed to drop down from last year's 5.13 gear ratio to a 4.88 gear that I preferred, especially with a big-block that could make up for less gear. Yukon Gears were stuffed around the ARB Air Locker and the Pro Rock was buttoned back up. In the rear, a van-width 14-bolt (3 inches wider than the 3/4-ton truck axle) had become a likely candidate, so a Yukon Gear spool and 4.88 gear setup were packed into the axle by Fenzel. What we had here is one of the first versions of the Yukon Gear spool, and the one you will order comes as a solid ring at the gear instead of being scalloped like ours was.
The Dynatrac front axle was already complete and proven off road, but we needed to drop do
Fenzel used an indicator to get just the right setup when he dropped the spool and gearset into the 14-bolt axle. The spool will not only be the lightest differential (or lack thereof) we could put in the axle, but will also allow the most fluid capacity, and generate the least amount of heat as there is no spin differentiation between the two axles. Spools are great off road and very predictable, but they get tiresome on road and are almost unbearable (on road).
Fenzel used an indicator to get just the right setup when he dropped the spool and gearset
Once Fenzel had the axle completed, he used an inch-pound torque wrench to check how much drag is in the setup. Once he was happy with it, the axle was filled with gear oil. When installing a new ring-and-pinion, it's best to drive it for 20 minutes, and then let it cool down completely to allow the gears to break in correctly and provide the longest, most reliable life. You should do this three times as well.
Once Fenzel had the axle completed, he used an inch-pound torque wrench to check how much

We handed the axle over to Forrest Moore once it was ready for the four-link. Moore starting mocking up some plates that he would later weld to the centersection to mount the upper triangulated part of the four-link rear suspension.
We handed the axle over to Forrest Moore once it was ready for the four-link. Moore starti
Orange County Transmissions had just finished giving a TH400 tranny a complete B&M parts overhaul while adding in a few of its own tricks for this truck (Turbo 400 Revival, p. 68). I hauled it up to Santa Rosa, California, to the Fabworx shop where Arrington added the new B&M torque converter and flexplate. We made sure to swap the output shaft because we were going from an NP205 output to an NP203 output, as this K5 was receiving the Off Road Design NP203/NP205 doubler kit.
Orange County Transmissions had just finished giving a TH400 tranny a complete B&M parts o
The ORD doubler kit and transfer cases were also proven parts from last year's yellow U.A. Chevy. They had done great behind the Ramjet small-block and TH350. Now I was about to see if they'd hold up just as well in back of a serious big-block and TH400 tranny
The ORD doubler kit and transfer cases were also proven parts from last year's yellow U.A.

SOURCES
B&M Racing 9142 Independence Ave. Chatsworth CA 91311 8-18/-882-6422 www.bmracing.com	Orange County Transmission
Dynatrac	West Texas Off Road
Fabworx www.fabworxinc.com	Yukon Gear www.yukongear.com
Off Road Design www.offroaddesign.com