[1971_c10]

Continuing on the updates ...

So I started to finalize my drivetrain setup as mentioned when I got the setup bars installed. Found yet another rabbet hole. My motor/trans down angle was sitting about 4.1 degrees down. Yikes. That's a tad on the high side. So I set off evaluating options. I've got that stroked LS, so Rob had sent me some bits to make new perches (the part that the motor mount bolts to and then bolts to the truss on the chassis) that pushed the motor up 1/2" from the ones that shipped with the chassis. So since those were just bits, I took to modifying them.

The goal was to get the down angle to 3.5 degrees with no transmission tail shaft spacers. So the engine/trans came out. I hacked the plates up that make up the perch and started "moving" the hole for the motor mount tube down. This was an iterative process. Die grind a little, bolt the plates in, set the motor/trans in, check clearances, check angle, repeat. After several iterations, I wound up dropping the engine down a tad more than 1/4", basically putting my oil pan resting on the cross brace part of the cross member. So me and the angle grinder went to work and put a shallow U to provide just enough clearance on the oil pan. Success! I got the motor/trans down to 3.5 degrees. With a 1/4" trans tail shaft spacer I get can get down to around 3.0-3.1 degrees, but then I may be into the back of the cab with the driveshaft which would require me to notch the back of the cab (this is at full bump only).

Oh, and on the driveshaft, I'm using Mark Williams Enterprises here in Colorado. Those guys are awesome. If you ever need a custom driveshaft check them out (they have more than just driveshafts). I'm getting a 3.5" 6061 aluminum driveshaft with 1350 U-joints. That will handle the 600 HP with no problems. It does impose a ~150 mph speed limit on the truck with the 3.70:1 rear gears, but with no roll bar/cage, I'm perfectly ok with that as the top speed. For those curious on why the driveshaft is the limiting factor, it has everything to do with the critical speed of the driveshaft. The critical speed is the speed at which the driveshaft becomes unstable, and you don't want that. Trust me. It's a matter of seconds before carnage starts to happen.

So here's a few shots of the stuff. The first are the finished perches (sorry, in this case I forgot to take pictures of the mods). The original No Limit ones on the left, my hacked up modified ones on the right. I got really lucky and found an epoxy spray paint that very closely matches the powder coat. The left ones are powder coated, the right ones are spray paint.

I also tossed in a couple shots of the finalized engine mounting and a comparison of the 1350 U-joint/yoke to the factory one.