Posted by Doc Dave [66.82.9.11] on Sunday, April 10, 2011 at 07:15:56 :
In Reply to: Re: Performance parts for 251cui posted by Terry in Bozrah [70.233.85.53] on Sunday, April 10, 2011 at 06:50:46 :
Search Phil's archive for Dennan overdrive.
Several of us have one in our trucks and it really helps with the stock flathead engine. It drops the revs about 500 rpm when it is activated, so it is then easier to get to 55 without over revving the engine.
If one re-powers, and especially if also a different tranny and/or axle is installed then it is not needed.
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