1971 GMC Donald

[mxerhale]

Thought of a few things as I was laying under the truck adjusting my trailing arm mounts up a spot because I felt a slight shudder at about 85MPH the last time I drove it to work and it seems as though the driveline angle is a little different now that the suspension has completely settled. Anywho...

I did get a new steering wheel finally and put it on over the Xmas break along with a new heater control panel that my good buddy custom made me.

Also pulled a plug after my 9psi hit to see how things were looking in there.

Hewittca, I didn't pull the wheel off, but i did see that the back side of the wheel is almost perfectly flush with the drum brake backing plate and I'd guesstimate the backspacing pretty close to 4" on those rear wheels.

[hewittca]

Originally Posted by mxerhale

Hewittca, I didn't pull the wheel off, but i did see that the back side of the wheel is almost perfectly flush with the drum brake backing plate and I'd guesstimate the backspacing pretty close to 4" on those rear wheels.

Awesome, thanks for checking!

[mxerhale]

I'm not sure if I mentioned somewhere earlier that I put in a 3 port Mac valve and an electronic boost controller that would hopefully allow me to adjust boost on the fly. After doing a bunch of data logs I decided to do some back to back tests and found out quickly the boost controller was doing nothing! Lots of more reading online and looking at Holley schematics helped me figure out where I went wrong and now it functions great. I can turn it down to about 4.5 psi and have still not gotten brave enough (nor had the need for!) anything over 9 psi. I typically keep it between 5 and 7.5 psi for just driving around in case I need a little passing power. I have it setup as boost by MPH in the Terminator X software and that seems to make it much more civilized.

Another thing that I haven't mentioned is my heater setup. I'm not a big fan of cold weather or being cold, but my 4" exhaust made me delete the original heater box so I got creative and installed a smaller one in the cab behind the glove box. My friend built me a little PWM controller so that the blower motor is essentially controlled by a rheostat and I ran some Amazon hoses to the defrost vents and one extra vent dumps on the foot well of the passenger side.

Last but not least, my friend finally found me an honest to goodness GMC front bumper! It came off of a Carryall and it has the perfect patina to match my truck.