I believe the GMC bigger trucks used the PontiayV8 in the later fifties, so a 400-455 Pontiac is a natural fit. Sell that six if you want. Many are looking for them.
Great eye......I'd be pulling that Funk conversion out of there also is the seller would part with it. They are a neat conversion and the Funk brothers story is a great one.
Yeah I'd build the 6. IF I had to have a v8 it'd be a pontiac to make it look like an original v8 gmc truck with some "internal" mods to build more torque. But like anthony posted above is were I'd head with the dropped axle, hopped up 6 etc. .
In the "dusty" as-found photo I don't see the lettering on the door. Was it just faded and still obscured with dirt, or did you add it after cleaning the truck? I'll add one more thing and that is put a conservative wheel tire package on it, including a side mount spare. I'm not a 100% leave-it-as-it-is die hard, but you have an elderly gentleman of a truck there and it would be a shame not to give it due respect. Your truck though, but you did ask for opinion I believe. Now do as you wish. Enjoy! Lynn
Just one more thing to add.... Any changes I'd do would be bolt on only, and I would keep the original stuff in case you or the next owner wanted to go back stone stock. When you start welding and cutting, the value as an original unmolested vehicle disappears.
The OP asked about the sbc/tri power. Not should I keep the 6. Happens every time. Derail. https://en.wikipedia.org/wiki/The_Derailers
Asking for opinions..I have had several multi-carb vehicles in the past and they can perform reliably, yes, you can have better performance/efficiency with a single carb..but multi-carb set ups up the cool factor. I currently have a SBC with tri power in my '39 Ford Coupe..reliable?, cool?, yes on both counts. People mean well advising you to keep the 6, but at the end of the day, you're the one who holds the title. Cool truck.
He said he wants to get rid of the 6, and, he's asking for opinions. I think he's getting good advice overall.
@YEZZI if you really want a v8 swapped truck, maybe a straight up trade for one is a good option. Lot of people value the truck you have for what it is - as is.
That is not a bad idea at all. The AD group I am in has new for sale adds popping up daily. Save a lot of work.
292-312 Y-block would also be a nice swap. Dress it up with 3x2 intake, T-bird rocker covers. You'll love the torque of a y-block.
Don't forget, that's a 6V. It's not the biggest project to change to 12V to go with a "new" engine, but it is another reason to keep the original if "traditional, period-correct" is what you're after. I, too, like the others, think the 6-cylinder would be a stand-out among a flock of SBCs. If you're really stuck on the 350 SBC plan, what'da'ya think about the look of an ol' school, cast iron, 4-barrel intake painted to match the block and heads? That will cruise with the best of them and still be first away from a green light. My all-time most enjoyable car to drive had a low-rise intake. It was super responsive around town, like a mantis on a bug........ scored at the top in the fun factor department.
You asked for opinions ? Okay, I'm of the opinion not to ask others how to build my stuff. You results may vary...
Thanks for all your opinions I agree with keeping it original however I'm not a fan of the six cylinder. I do have a rebuilt 347 Pontiac that I can add a tri-power too. I have the original hydra-matic that came with it. I put one in my 57 GMC years ago here's a pic.
If a V8 is what you want (and who wouldn't), now you're talking. GMC truck with a Pontiac V8. Who could ask for more..........
In that case here: https://www.facebook.com/marketplace/atlanta/?ref=notif&hoisted_items=1005845190314008 $4000.00 OBO
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