Gmc 5500

[markambler]

This GMC 5500 has a 351 V6 with man. 5 speed
Once owned by Divers Institute of Technology in Seattle Wa.
I am currently restoring with plans to repaint with the DIT colors
Thinking about the possibility installing a BBC 454
At this point the trany id is questionable, on the side if it below and to the right of the New Process logo casted in the case is CS5871 with AE below the numbers. above that is 099 stamped
The service manual calls out a 435GL as standard with 435GD,540GD or a 540GL as options
Have not found info on a NP CS5871 yet, but I have read that the NP transmissions that should be in this rig have reverse to the right and down, this one is to the right and up
any info will help

[70cst]

Hey markambler ...

to the forum and from Ohio ...

That is a sweet project that you have

[C10 - C90 Bill]

Welcome to the site.

Cool Bus.

Of course I would be keeping the V-6 though. I sure do like those engines.

Bill

[markambler]

at this point I am going to try a holly 500 cfm on it to see how that preforms

[factorystock]

It appears you have one of this

[C10 - C90 Bill]

I had a Clark like the one on the left. What I liked about it, is how the gears were spaced, along with having a 2-Speed Rear.

You could drive it on the road, reasonably, like a 5-Speed: 2 Lo, 3 Lo, 4 Lo, 5 Lo, 5 Hi

or like an 8-Speed: 2 Lo, 2 Hi, 3 Lo 3 Hi, 4 Lo, 5 Lo, 4 Hi, 5 Hi. Notice the Irregular Shifting Sequence. This trans allowed you to only have to Split-Shift the Rear back to Lo Range, twice.

Bill

[jaredg]

Nice - Another bus!!! This looks like a 1970-72 with a Carpenter Body! Very cool.

[markambler]

yes the transmission is a 540 series
since my last post i have been working on getting the motor dialed in
i adjusted the valves, found they were tight, this increased the vacuum from 15in to 19.5 in
installed dual exhaust with H pipe
installed a holley 500 cfm
timing set at 5 deg BTDC , to get this setting i set it at the 10 deg. as the book says, took it out and ran the same course and just turned the distributor a little each round until it ran the best, got it home and put timing light on it and found it is at 5 deg.
it is now running clean and strong
still looking at the possibility of getting more hp by getting a 351M or bigger, i have a guy looking thru his yard of trucks for any V6's, he thought he had a 478
if the price is right i would do the swap
the 351C i have now would be a great engine for a pick-up

[C10 - C90 Bill]

Depending on what you are looking for, I myself would be happy with the 351. I had a 305 V-6 in a '62 GMC 4000 and it pulled just fine, hauling 2 1/2 Cords of Green Firewood to boot. The 305 was actually an "E" out of a pick-up truck and it still did fine. Now I was used to power as I drove a 478 V-6 for years. The 478 is a great engine and would pull 20,000 plus pounds without hesitation, but in comparison, the 305 was pretty amazing. The 351 would have been a plus in my truck.

Bill