gas block with diesel heads

Discussion in 'Diesel Engines' started by adamanderr, Dec 13, 2007.

  1. adamanderr
    Joined: Mar 2006
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    adamanderr Junior Member

    :?: Where should i look for info or possibility of converting a gas block to run on diesel? is it as simple as bolting on compatible diesel heads, since fueling and valve etc are in head? what about having a head machined?

    Joined: Oct 2002
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    FAST FRED Senior Member

    GM failed miserably in their attempt, as the loads on a diesel 16 to 20 Compression ratio are different from a gasser.

    Simply find a small diesel car or truck engine , and use that.

  3. CDK
    Joined: Aug 2007
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    CDK retired engineer

    If you have enough resources at your disposal, anything is possible.
    Volkwagen has used a gasoline block for their small diesels. They changed the head, the crankshaft, flywheel, pistons, connecting rods, added a Bosch fuel injection pump and voila, the first VW Rabbit diesel.
    After a few years they also changed the block.....
  4. Frosty

    Frosty Previous Member

    How can bolting on some heads make a deisel? Bit more to it than just getting fuel in. You need 22:1 compression as well. This will knock out your inferior block, crank,pistons ,rings etc.

    Its difficult enough converting truck deisels to boats let alone the way your doing it.
  5. old750
    Joined: Sep 2007
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    old750 Junior Member

    GM made a gas block diesel, and apparently it was not reliable.
  6. bxbbuddy
    Joined: Dec 2007
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    bxbbuddy New Member

    Yes, indeed... And the impression it made upon a public used to the quiet and reliable power of big block Oldsmobile gas engines soured the diesel market for the Big Three for twenty years. Even now, the Big Three (Now no longer so 'Big' anymore!) do not offer a diesel powered passenger car.
  7. Frosty

    Frosty Previous Member

    I agree --not in America any way. America has never made a car.

    Try the Jaguar diesel,---your going to get a shock.
  8. marshmat
    Joined: Apr 2005
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    marshmat Senior Member

    A diesel might have compression anywhere from 16:1, to 20 or 22:1, sometimes more. Gasoline motors rarely exceed 9 or 10:1 except for highly tuned performance engines. The nature of the diesel cycle is such that it tends to produce more torque than an Otto-cycle engine of comparable power, and tends to produce this torque at a lower RPM. All of this translates to pressures in the cylinders and loads on the moving parts that can be, in some cases, double or triple those found in the gasoline counterpart.

    So, don't waste your time trying to build a diesel out of a gas block. Stick with what the engineers originally intended for the thing, or buy a diesel.

    I too am surprised by the dearth of diesels in the car and light truck market over here. Driven any of the newer VW TDIs lately? They go like a bat outta hell at 1700 RPM, they start in seconds at minus twenty celsius, and they run smoothly enough that passengers don't realize what it is until you tell them. (Oh, and of course, a thousand kilometres on 55 litres of fuel.) Mercedes is starting to get them back here (the Smart car, and the Bluetec unit in the M-class) and of course diesel's always an option with big pickups.... but how we would love to get access to some of what the Europeans have.....

  9. Frosty

    Frosty Previous Member

    Its the long stroke of the diesel that gives it its compression and its stroke also gives the torque.

    Out of shear curiosity where were you planning to drive the pump from.

    Some engines drive the oil pump from the distributor.
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