[Wild Turkey]

I know there's a forum on them but just checking here for anyone else fascinated by these oddballs.

305 to 478 cid with same external block size. HEAVY beasts.

My granddad ran 478's on his irrigation wells while my dad preferred Chrysler 354's and 413's.

I have a 401 sitting around that's great for making gearheads look confused.

 

[2old2fast]

Buy stock in an oil company , those motors love to drink fuel !

 

[joe_padavano]

The problem with these V6 motors (and the V12 they spawned) was that they were designed to emulate diesels. Heavy, low RPM, and earth-moving torque.

GMC also offered a 637 cu in gasoline V8 based on that V6 architecture. It used the same 60 deg vee angle, so it needed a balance shaft to run smoothly.

You may know that GMC even offered diesel versions of the 351 and 478 V6s, called Toro-Flow engines. Sadly, these were not successful - a lesson GM apparently forgot when they built the Oldsmobile Diesel.

I didn't know that there was also a twin-turbo diesel version of the 637 V8. That's got to be rare.

Here's a good article that I hadn't seen before.

 

[Wild Turkey]

dry weights:
305A = 738 lbs.
305B = 771 lbs.
305C = 840 lbs.
305E = 795 lbs.
351 = 860 lbs.
401 = 880 lbs.
478 = 925 lbs.
702 = 1485 lbs.
637 = 1219 lbs.

478 power
478M V6
Gross Horsepower 254 @ 3700 rpm
Gross Torque lbs. ft. 442 @ 1400 rpm

Not much compared to modern engines but would run forever