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motor_jet
11-26-2002, 09:38 PM
hey guys kick this one around. its big money but an interesting concept. the flat crank makes huge tork. and it has been done. warren johnson was competitive with it. the pontiac heads and intake evens up the runners almost as good as a ford. and if you go with a 450 bore it cures the design flow problem. oh well john deers make a lot of tork but you could be the only guy out on the lake with an 8 cyclinder harley
Infomaniac
11-27-2002, 07:25 AM
motor_jet:
hey guys kick this one around. its big money but an interesting concept. the flat crank makes huge tork. and it has been done. warren johnson was competitive with it. the pontiac heads and intake evens up the runners almost as good as a ford. and if you go with a 450 bore it cures the design flow problem. oh well john deers make a lot of tork but you could be the only guy out on the lake with an 8 cyclinder harleyGot any pictures of it?
lghtnin33
11-27-2002, 10:55 PM
what up mj ? what is a flat crank? your a master at this stuff, please enlighten us!!! and how hard is this crank to find? you said it is $$$ like how much?
SK48
11-28-2002, 06:38 AM
It works well. Sounds funny when running. Several boat guys used them in the 80's, most engines were from Mark Donahue the sports car racer. Harry Christensen from Advantage used them for Kilo record passes in ET boats and still has the Kilo record in ET II with a flat crank shaft chevrolet.
Craig
11-28-2002, 07:00 AM
A "flat" crankshaft means the throws are 180 degrees apart - i.e., all in the same plane - rather than radially dispersed at 90 degrees as in most eights. If you were looking straight down the centerline of a 90-deg crank, with the first lobe at the 12 o'clock position, the second lobe would be at 3 o'clock, the third lobe would be at 9 o'clock, and the fourth lobe would be at 6 o'clock. The reason flat cranks are used in (short stroke) racing V8 engines, is that they produce even firing intervals in each bank of cylinders. That makes for an optimum 4-into-1 header design. the penalty is that the flat crank is, mechanically, not as well-balanced as the 90-deg crank.
Craig
Infomaniac
11-28-2002, 08:22 AM
A horizontally opposed engine has a flat crank. Lycoming, Continental and VW.Probably the Corvair engine also. The engines were flat too.