Pietenpol-List: jeep eng
Posted: Mon Jul 06, 1998 5:18 pm
Original Posted By: rdecosta(at)autoeurope.com (Richard DeCosta)
so far this is what i have found out about the 134 L flathead jeep engine, asa possible substitute for the ford model A.3 1/8 bore4 3/8 stroke60 hp at 4000 rpm39 hp at 2000 rpm105 ft-lbs torque at 2000 rpmkind of sounds like a model a ford...And it does this on 33% less cubic inches!(sametorque, same hp,same rpm, 33% less cid to feed..) Probably becouse it achievesits power by better breathing. IE, bigger valves, Bigger ports in the heads,etc. And maybe a longer throw.Looking over one of these engines, I have also found that the block is about 1/3as large as the ford, so it should also be lighter.The only real problem that I can see is the length of the rear maim bearing. Sofar I have not seen a stripped block, and can find no body who will allow meto tear their jeep apart to look.A final note:The volkswagon engine runs from the front on a very narrow bearing, that was neverdesigned to swing anything like a propeller.I know that with the vw, "Great Planes" has modifyed the front bearing for greatersurface area, and does recommend this mod. Also they have recently come outwith a new bearing support that allows MUCH GREATER cid from their type 1 enginesthan they used to. For I think.........up to 125 hp....but i won't swearto that.I read recently about a fellow whe built a curtis hawlk at 80% scale. For powerhe installed a 350 HO chev engine in the plane that had a standard size (but4 bolt)rear main.His plan was to run the engine direct drive at 2500 revs, rather that go for 5000that the engine was designed for...There was no statement, ( or apparent concern)about sideways propeller loads.Lastly, (then I'll shut up) they say that one should never use any but a wood propon the vw, becouce of the weakness of the front main bearing. Apparently thewood prop does flex, and there-by does reduce the crosswise propeller loadson the weak front bearing.Some comments if any would be nice.BOBP.S. Can somebody recommend a good book for making homemade propellers ? The book : Propeller making for the Amature is out of printhttp://www.mailexcite.com________________________________________________________________________________
so far this is what i have found out about the 134 L flathead jeep engine, asa possible substitute for the ford model A.3 1/8 bore4 3/8 stroke60 hp at 4000 rpm39 hp at 2000 rpm105 ft-lbs torque at 2000 rpmkind of sounds like a model a ford...And it does this on 33% less cubic inches!(sametorque, same hp,same rpm, 33% less cid to feed..) Probably becouse it achievesits power by better breathing. IE, bigger valves, Bigger ports in the heads,etc. And maybe a longer throw.Looking over one of these engines, I have also found that the block is about 1/3as large as the ford, so it should also be lighter.The only real problem that I can see is the length of the rear maim bearing. Sofar I have not seen a stripped block, and can find no body who will allow meto tear their jeep apart to look.A final note:The volkswagon engine runs from the front on a very narrow bearing, that was neverdesigned to swing anything like a propeller.I know that with the vw, "Great Planes" has modifyed the front bearing for greatersurface area, and does recommend this mod. Also they have recently come outwith a new bearing support that allows MUCH GREATER cid from their type 1 enginesthan they used to. For I think.........up to 125 hp....but i won't swearto that.I read recently about a fellow whe built a curtis hawlk at 80% scale. For powerhe installed a 350 HO chev engine in the plane that had a standard size (but4 bolt)rear main.His plan was to run the engine direct drive at 2500 revs, rather that go for 5000that the engine was designed for...There was no statement, ( or apparent concern)about sideways propeller loads.Lastly, (then I'll shut up) they say that one should never use any but a wood propon the vw, becouce of the weakness of the front main bearing. Apparently thewood prop does flex, and there-by does reduce the crosswise propeller loadson the weak front bearing.Some comments if any would be nice.BOBP.S. Can somebody recommend a good book for making homemade propellers ? The book : Propeller making for the Amature is out of printhttp://www.mailexcite.com________________________________________________________________________________