Diesel to gas reversion

[bigblockv6]

Actually GMC did have a twin turbocharged DT478 Diesel used for military ambulances and fishbowl buses, they never gave out any horsepower ratings though. The D351 was rated at a 130 horsepower, so that was actually less than the 305 and the DH478 was last rated in 1974 at 150 horsepower only two more than the 74 305C V6.

[BobBray]

DT478 in a Fishbowl??? I did see DH478's in the 'baby' TDH 3301's, but not the turbocharged version. Interesting.

[turbobill]

I do remember the turbocharged Army buses. Had two of them at the local military base in the late 60's.

By the time I was in the service, the Toro-Flows were being changed out for triple nickel Cummins V8's. The triple nickel was one gutless engine!

[GMJakers13]

hey thanks for the input! BobS, As far as dealer installed originality goes, I have my doubts but anything is possible. Everything looks well-done, but I have definately done both sides of work, rigged and proper, with a heavy lean to rigged, so maybe my eyes are off. If you want it done professionally, then think how they would have done it. cleanly and with new or nicely refurbished parts, and maybe an extra support or two properly bolted in the right places. Barring internal damage itwill be keeping the D351, and im already on the hunt for stainless steel tubing to make turbo manifolds. my next question is about the injector pump assemblies. how different was the timing on them from the D478 to the D351? Im new to the diesel ordeal but if its feasible and remotely close would it not add a touch more power putting the 478's pump on the 351? And thanks for the offer Jolly I will keep it in mind. I did actually mean about parts changing and making it a gasser but after looking through the factory service manual and listening...haha. And Alan, did that happen to be the DH478 in your boat? as far as fuel consumption goes, a winter truck is all she will be for a while, so guzzle away, so long as dependability is there. after a shutdown or two, a spicer with overdrive is on the list, if I can find one in decent order or worth going through.

[GMJakers13]

and dual tanks, factory set as well. the switches are driver side, on the floorboard by the seat.

[bigblockv6]

GMJakers13, I'm curious how is the power of the D351 in a pickup truck for a rating of 130hp, is it responsive or sluggish?

[GMJakers13]

bigblockv6, I would love to say but cant seem to get it to pop off. I havent ran a full set of procedure but pushed fuel to the pump and still wont run.

[bigblockv6]

I have to admit when it comes to Diesels I'm no expert, my interests are primarily with the gas GMC V6, ask me a question on one of them and it's never a problem.

[GMJakers13]

im pretty sure that it's just the pump. Id like to find a good 2wd that I can put a gasser in. ive got a 305 and spicer 4spd out of a 66 school bus with 48k on the set coming from California. have been thinking about some port work and a little intake modification for it. one day id like to see a billet crank and rods for one of the little 305s with a small dual turbo setup. dreams. Bigblockv6, can you swap the crank from the larger displacements, the 3.86in, in to tho 305 without much issue?

[bigblockv6]

Myself, I would not waste time and money on the 305, just go with a bigger V6. I pulled the 305 out of my 68 K2500 and replaced it with a 478M V6. Putting a 3.86 stroke in a 305 will require custom pistons, the longer stroke will make the pistons travel slightly above the bore, some say you can have the stock pistons machined down. You want a stroker V6 GMC made a 379 from 1973-74, basically a 351 with a 478 crankshaft. Same thing with the 432, a 401 with a 478 crankshaft.