quick question

[crites_72]

a guy i work with has an 67 or 68 GMC 6500 dump truck parked in a field. He just got the place from his grandfather and there is so much juck setting around. So any way my question is, the truck has a big block in it. and is there a way to tell what size the engine is? it turns freely has antifreeze in it and the oil looks good. ran when parked there but i havent tried to start. im going to take a chance and bring it home if its like a 396 or 427, is there a way to tell. i know on a SBC the casting numbers behind the left head on the block but i've never messed with a big block. the truck itself is trashed cab by the windshield is rusted in pieces. but the windshield is perfect. but anyway the any help with my question would be great. thanks everyone

[JimKshortstep4x4]

If you can see the engine pad on the right front of the engine write down the suffix code and the engine can be identified from the code.

If the engine is a "tall deck" engine you may not want it.

Jim

[crites_72]

I got some pics. of the truck and engine. if that would help. not the best they're off my cell phone. why wouldnt i want a "tall deck", and where exactly is the engine pad? my plans are to drop it down in the front of my 68 chevy with my saginaw 4 speed behind it. truck was originally a 283 3 speed truck.

[Longhorn Man]

that would be a 366 or 427 tall deck. IMO, not worth the trouble or expense. If it is a 427, the steel crank is worth a few bucks... but otherwise, either of those engines would be slow reving low RPM now HP engines.

[crites_72]

i can get the motor for like 50 or 75 bucks. still not worth it?

[PanelDeland]

Not unless you need a boat anchor.

[Prostreet 72]

Originally Posted by crites_72

a guy i work with has an 67 or 68 GMC 6500 dump truck parked in a field. He just got the place from his grandfather and there is so much juck setting around. So any way my question is, the truck has a big block in it. and is there a way to tell what size the engine is? it turns freely has antifreeze in it and the oil looks good. ran when parked there but i havent tried to start. im going to take a chance and bring it home if its like a 396 or 427, is there a way to tell. i know on a SBC the casting numbers behind the left head on the block but i've never messed with a big block. the truck itself is trashed cab by the windshield is rusted in pieces. but the windshield is perfect. but anyway the any help with my question would be great. thanks everyone

You can figure it out based on the bore of the bolck you have. To figure the bore and stroke, go to Google and type in engine calculator. A few different ones will pop up. These will allow you to configure all different bore and stroke configurations and tell you the cubic inch result.

For what you are doing, you can input the 396 or 427 data to figure out what you have. Or simply throw a calliper on the bore and do some surfing on hte net under 427 bore and stroke.

[70rs/ss]

What, a tall deck 427 isn't worth it?? Are you guys kidding?? In stock form, yes a pig, but it obviously needs a rebuild, and with a tall deck block he can add a stroker crank with zero clearance issues, get a stoker assembly with crank, rods and pistons, then he'll have a near 500 ci BBC, now again why is a tall deck 427 not worth $50?? Heck, tell me where it is I'll buy it!

[Longhorn Man]

well, it's almost worth 50 bones in scrap value alone, even with the lower scrap prices.
Stroking a tall deck and building them up... doesn't that end up being close to the cost of a 502? I've always heard it takes a butt load of money to make one.

[WIDESIDE72]

Originally Posted by 70rs/ss

What, a tall deck 427 isn't worth it?? Are you guys kidding?? In stock form, yes a pig, but it obviously needs a rebuild, and with a tall deck block he can add a stroker crank with zero clearance issues, get a stoker assembly with crank, rods and pistons, then he'll have a near 500 ci BBC, now again why is a tall deck 427 not worth $50?? Heck, tell me where it is I'll buy it!

I agree. There is definitely nothing "WRONG" with a tall deck motor. Depends on what you want to do with it. IMO, it would make a good engine for a tow rig. I would get the casting #s and go to Mortec.com and see if it is a 366 or 427. Personally, I would not bother with a 366. I am not sure of the difference in it and a 427, bore stroke or both. My dad was a rig welder and had an 80 GMC 1 ton w/ a steel 3/16"steel bed he built with tool boxes, (full of tools) and hauled a gas Lincoln 200 amp welder and oxy-acetylene cutting rig on it. We replaced the tired stock 454 with a tall deck 427 with a torque type RV cam, 69 Vette 390 hp cast iron holley flange intake (found it at a swap meet for $50 and ran better than the Edelbrock Performer we put on later, so we swapped it back) and Blackjack headers, and it pulled like a train! The only issue was we had to run spacers under the low deck intake manifold, and bought a Mallory dist. to get away from the stock points dist w/ governor.

[WIDESIDE72]

I think the issue with the tall deck motors was the heavy stock pistons due to an extra (4th) ring (?)

[drivethechevy]

everthing can be machined id pick it up if it was a 366 or 427 talldeck

[crites_72]

thanks for all the help. the goods and mostly the bads. it dont look like im going to be getting it anyway. he wont part with the motor without selling the whole truck and the wife says no. shes probably right nothing left of the truck that rust hasnt ate away. i mean even the doors are held on with barn door hinges welled to the outside. even the windshield pillar is rusted in two pieces. but it does run and move. thanks again for the advice