Vortec upgrade to 89 5.7 L reverse rotation motor

dmohring

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Apr 6, 2018
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16
Yes if the cam turns the same regardless of RH or LH crank direction, then I should be able to use any off the shelf performance upgrade cam.
 

dmohring

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Apr 6, 2018
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16
ok I am thinking about it more and I see why now. The valve open/close sequence is reversed on a RH engine hence the reversed firing order and a "special" cam. dang.
 

Bt Doctur

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Aug 29, 2004
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19,484
Yep., you got it. If the block is viable and the trans is reversable then I would convert to a standard LH motor during the rebuild. Now you can use a standard LH cam
 

dmohring

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Apr 6, 2018
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16
Its got a Velvet drive model 10-17-004. I dont know if it can run in reverse. My concern about reversing the motor direction beyond if the trans is reversible is what about:
crank - looks like I need a different crank
water pump - need new one?
sea water pump - need new one?
alternator - need new one?
Anything else?
Thanks
 

alldodge

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Mar 8, 2009
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You have a ski boat so the prop is made for RH rotation. It is possible to get a LH prop for it but need to think about a couple other items which one is critical and the other may cause handling issues.

The rudder is off set to one side of the prop which may or may not cause some issues

The big one, is what transmission do you have? Not all can be shifted to opposite direction for forward under full load.

Edit: looks like you got to the question I was wondering about
 

alldodge

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Need to do some more looking but look at the trans input shaft area and see if you can find the Word "TOP" and an arrow
 

Bt Doctur

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Aug 29, 2004
Messages
19,484
and to reverse the trans rotation remove the pump bolts and rotate the pump to the opposite index mark
 
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