What can we pillage from a 6.7L?
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What can we pillage from a 6.7L?
Since so many of the parts between the 6.7 and the 5.9 are the same, what can we plunder to make more power?
I've wondered if the pistons on a 5.9 or short enough to allow using the 6.7L crank without smacking the head.
Stroking the 5.9 with the 6.7L crank would take you up to almost 6.4L and raise compression.
Maybe a thicker HG would allow the use of the bigger crank?
The rods and bearing sizes and all that are the same between 6.7 and 5.9.
jh
I've wondered if the pistons on a 5.9 or short enough to allow using the 6.7L crank without smacking the head.
Stroking the 5.9 with the 6.7L crank would take you up to almost 6.4L and raise compression.
Maybe a thicker HG would allow the use of the bigger crank?
The rods and bearing sizes and all that are the same between 6.7 and 5.9.
jh
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You'd need a taller deck, or a shorter compression height on the pistons to do the stroker. Would the crank even fit in the block? Custom pistons would be cheaper than a custom block I'd imagine.
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Custom block-- that's funny! Maybe for 20K or so!
The crank will fit in the block just fine. the 6.7 and 5.9 share over 80% of their parts.
As far as I know, the rotating assemblies are the same fitment, just longer stroke and bigger bore for the 6.7L. The rods are the same, but the pistons for the 6.7L are shorter to allow the longer stroke.
If I thought my block could handle being bored to the 6.7L size, I'd try it, but it's like 3mm larger, and that's too much overbore imo. Weak walls are not your friend...
The crank will fit in the block just fine. the 6.7 and 5.9 share over 80% of their parts.
As far as I know, the rotating assemblies are the same fitment, just longer stroke and bigger bore for the 6.7L. The rods are the same, but the pistons for the 6.7L are shorter to allow the longer stroke.
If I thought my block could handle being bored to the 6.7L size, I'd try it, but it's like 3mm larger, and that's too much overbore imo. Weak walls are not your friend...
#4
If I remember right from my old hot rod days. A longer stroke with the same bore increased torque and lowered top RPM's. The same stroke with an increased bore increased horsepower and raised top RPM's. This was on gas engines, but since a diesel is by nature a torque engine, a longer stroke should help it. Another thing you would have to check would be that the piston skirt did not contact anything at the bottom of the stroke.
A vendor selling 6.4 stroker long blocks with a good cam already installed might make some money.
Larry
A vendor selling 6.4 stroker long blocks with a good cam already installed might make some money.
Larry
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To p-pump a CR, you need a special timing case, a 12v case won't bolt up. I imagine a 6.7 would be similar. Still doable, just not as easy as a 24v.
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what different about the gear case? if something needs to be machine that's easy for me to get done. my dad owns a machine shop. if its just completely different, are they available. to have the displacement is worth it in my opinion to build an engine. on a side note i just got a phone call from my buddies at the junk yard. they just got a 200hp 6.7L out of a UPS truck with my name on it if i want it.
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