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convert 350 olds diesel chevy truck from auto to 465 ?

Discussion in 'The Garage' started by R72K5, Aug 12, 2004.

  1. R72K5

    R72K5 Banned

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    what 11" or 12" flywheel would i need to find that would work on a 350 olds diesel for an 81 chevy pickup with a 435 trans mechanical linkage like a gm truck before 85 would have ?
    what about a bellhousing ? i take it olds buick caddy pont all used same 90 degree bell pattern for 307-455 gads and diesel both ?

    are diesel auto trannies anything special in 81 c-10's with the 350 olds diesel ?
    any places or ppl on the net to ask about any of this info ?

    thanks for anything
     
  2. diesel4me

    diesel4me 1 ton status Premium Member

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    I have seen 2 chevy trucks with the olds diesel with a SM465,so evidently GM did make something factory to bolt them up--I never looked that close at them,I spotted them in the junkyard while looking for a motor--I dont think they were 4x4's,I think they were 2WD.Both trucks had the motors hanging out of them,trucks were laying on their side,looked like they were ripping the motors and trannies out with the forkloader,because scrap went up to 60 bucks a ton around here again,and they are crushing everything--even trucks in the 90's are being crushed daily--there's just too many coming into the yards,they have no room--I said to myself that olds deisel tranny setup must be worth something to someone--but its all in the crusher now.The olds diesel has a bad reputation for not living very long,and well deserved too,most of them around here I've seen were purchased new by the local phone company in 1980-81,by 1983 over 40 trucks with that drivetrain were auctioned off because they blew most of the motors--a friend bought 2 trucks for 2500 bucks that only had about 30 thousand miles each,and both had replacement motors,that also were junk --maybe the drivers beat the crap out of them,but most every olds diesel has vanished from the face of the earth around here--my friend re-powered the trucks with 455 olds gas motors from delta 88's,it was practically a bolt in swap,but he had to pull the first motor out again because he found out the tourque converter has a different stall speed for a diesel(he was anal about having it perfect,but I drove it,and I think I could have lived with it-),as far as I know thats about the only difference in the automatics--.Maybe you could use a blowsheild for an olds gas motor to install a SM465,(maybe the gas 350 olds manual flywheel will work?? /forums/images/graemlins/dunno.gif)or a bellhousing adapter to make the olds motor bolt to a chevy bellhousing,but the thickness of the adapter will not allow the tranny pilot shaft to go all the way in,and will mess up the clutch position too,so that probably wouldnt work without lot of aggravation. I think you should look for a parts truck with the 6.2 or 6.5 diesel and the SM465 already installed,and swap the whole drivetrain over,youd be better off in the end. /forums/images/graemlins/crazy.gif There might be more info on the net,try using google to do a search,there are lots of diesel websites. /forums/images/graemlins/crazy.gif
     
  3. R72K5

    R72K5 Banned

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    holy crap good info,

    i figured 2wd was the deal on this olds 350 diesel subject, yep, good deal, works for me, i couldnt care any less if no 4x4 oens were made,

    i like the 455 gas conversion idea, ill remember that one, but did the 455's get much of a low RPM torque producing camshaft like what would be needed in a work performing truck ? and what axle ratio would be in a an 81 diesel 5.7L/auto trans c-10 pickup with 12 bolt rear ?

    i agree totally with the yards and trucks and parts avaalblity, yes, they dotn keep anything older than ten years or so old anymore, poof all gone, nothing comes up anyways anymore, a few years back there were still some 67-72 being pulled intot he yard, but never hardly anymore, rare, and no K5's no burbs, no anything cept pickups vans and duallies and cars and big trucks all mid late 70s and newer


    lemme know if you know of any olds engine drivetrain related sites!

    another better way IMO would be to just put in a straight six or sbc tranny with gas converter for the auto trans and be done with it after draining tank out and swap gas engine compartment and cab harnesses in too, in which i can do easily, oh and swap in vacuum power brakes in place of the hydroboost system, in which im gonna do anyways no matter what

    thanks /forums/images/graemlins/laugh.gif
    R
     
  4. u2slow

    u2slow 1/2 ton status

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    Try http://www.olds-diesel.com/

    The '81 TH350 should be a lockup design, and maybe a different stall converter as already mentioned. It might have a multi-fit case... so it fits BOP and GM pattern. I think most the cars used a TH200R4. Might be nice for economy's sake.

    The 260 Olds diesel could be had with a manual trans, and is the same balance as the 350. It only holds a 10.5" clutch though.

    The BOP manual trans bellhousings should be the same from 65 to 79 or so. You'd have to machine the center hole for the larger SM465 bearing retainer, but an SM420 should bolt right on.

    Ive also seen a homebrew BOP-to-GM adapter that was fashioned from 1/8" plate. I know it sounds flimsy, but 4 of the six bolts line up, and the plate only adapts two of them. This could work for a manual or auto trans.
     
  5. dyeager535

    dyeager535 1 ton status Premium Member

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    Olds 403's are a pretty good diesel engine swap...same physical size, since all the Olds Small blocks are externally the same. 455 gets you into BBo vs SBO differences.
     

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