big block v6

[joukaishou813924]

Finally found a big block v6 in a 68 gmc 3500, thinking bout yanking it just to have for a future project, I mean when I can build it from stock 305 cubic inches to a massive stock 478 cubic imches it sounds like a fun engine for something. What do you guys think, ever had one or heard of them?

 

[42chevy]

I have heard of them but don't know much about them. If the price is right I would get it, it will be an unusual engine and great conversation starter!

 

[hotrod preacher]

i agree w/42--if its cheap, i'd snag it and save it for build of a future project....

 

[joukaishou813924]

$188 plus tax, I need to go back and figure out what engine it is still, iy looks like a messed up 350 because the heads aren't mirrored like on most engines, they're staggered

 

[dmw56]

They are big heavy truck engines. GMC used 2 of them and made V12s.

 

[flatheadgary]

is it just me or does a big block v6 sound like an oxymoron?

 

[dmw56]

is it just me or does a big block v6 sound like an oxymoron?

If you ever saw one, you wouldn't! They are "BIG"! Up to 478 cubic inches then there is the Twin 6 702 cubic inch V12.

 

[cycledog]

something like this?

 

[joukaishou813924]

Yup I think they're close to the same physical size as a chevy 350 but I'm not sure. I do know the bore goes up to 5.125 inches

 

[dyce51]

is there any performance parts out there for these engines?

 

[R Pope]

They're big, heavy, low-RPM truck engines, not very powerful in the trucks they came in. If you want the different look, go for it, but don't expect much. I've driven trucks with them, they use gas like a flush toilet! About as much power as a 283 2bbl.

 

[Gregster]

I'm sure you could get someone out there to custom grind a BIGGER cam for it ! Then a little port work , maybe a bigger carb , some custom zoomies , then fella's you have a hot rod v-6 ....... take the ball and run with it !!! [cl

 

[Blue Eyed Devil]

They're big, heavy, low-RPM truck engines, not very powerful in the trucks they came in. If you want the different look, go for it, but don't expect much. I've driven trucks with them, they use gas like a flush toilet! About as much power as a 283 2bbl.

Exactly right. Just because it is "different" doesn't mean it is good. These engines were not very popular for a reason...

 

[Sam_Fear]

Exactly right. Just because it is "different" doesn't mean it is good. These engines were not very popular for a reason...

Not to be contrary, but it begs the question - why did GM build it? A heavy, no power, gas hog. What's the history?

 

[roddguy1]

Not trying to be a jerk here, but I think the only performance upgrade I'd add to one of those would be a chain. and then hang it on the side of a ship.
Interesting yes, practical, not at all. It's kinda like the 366 big block Chevy engines out of old trucks. There out there, but just not really a performance engine, and pigs on fuel.

 

[joukaishou813924]

Only performance upgrade I've heard of was an ignition upgrade and on the hamb I stumbled accross them talking about using 2 superchagers on them, the compression ratio on them is 7.5 to 1, so forced induction is also an option

 

[cycledog]

Actually they are kind of fun engines. I have a 305 in my 64 GMC. I put on a 500 holley 2bbl,
pertronix ingnition, pertronix hi output coil and dualed off the exhaust. Runs great. They have a very large block. My truck takes 36qts of coolant and the oil change is 6 qts.

You can modify a Buick v-6 distributor to get true electronic ignition. Be differnt, have fun, thats what its all about.

For more info check out www.6066gmcguy.org/

 

[DA34GUY]

Not trying to be a jerk here, but I think the only performance upgrade I'd add to one of those would be a chain. and then hang it on the side of a ship.
Interesting yes, practical, not at all. It's kinda like the 366 big block Chevy engines out of old trucks. There out there, but just not really a performance engine, and pigs on fuel.

I used to have 2 of them, about 40 ft apart tied together with a chain,
20 ft under water , out infront of my old house on the Colorado River, with floats tied off it to tie boats up to.
They make great anchors, that about it.
Hell they weigh as much as a 454 BB
They about as uslees as t*ts on a Nun.[S[S

 

[R Pope]

"Why did GM build it?" Well, it was a long-lasting, reliable engine in a truck. Designed in the '50's when gas was cheap. Lug all day, and thrived on neglect. Trucks were limited to 45 MPH highway speeds, too, remember.

 

[dmw56]

They may be interesting and different but they only make about 200hp and 400lbs of torque. A good SBC can make that much torque with even trying.

But if interesting and different is what you want go for it! [