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Jackshafts

To: Dan Neff <neffster189@yahoo.com>
Subject: Jackshafts
From: "John F Sandhoff" <sandhoff@compctr.ccs.csus.edu>
Date: Wed, 9 Feb 2000 15:16:28 PST8PDT
Dan has queried:
> Ok, i confess. This shadetree mechanic is DYING to 
> know what the #%!! a jackshaft is!?!

It's a camshaft with no lobes :-)

The 2000 engine is really just a stroked 1600 with an overhead
cam. Stroking is easy: change the crank, conn rods and pistons.
That overhead cam was a bit harder to fit in, but Nissan managed
to do it without any major redesign: replace the camshaft with a
jackshaft - use the same gears and chain setup as is in the 1600.
The distributor and fuel pump get driven by it.

Now, add a second gear on the jackshaft, and run a long chain
up to the real camshaft mounted in the head. Presto - OHC engine
out of a pushrod design. Clever (kinda), cheap ('til the chain breaks),
and 39 more horsepower.

My apologies to everyone that already knew this..

-- John
     John F Sandhoff   sandhoff@csus.edu   Sacramento, CA


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