Best Headers
#1
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Hi there,
i know its a question that all of you hered but but i am going to ask it again!
Which are the best headers out there for 502mpi v-belt ??
just saw these : http://www.cpperformance.com/product...t-headers.htmc
i know its a question that all of you hered but but i am going to ask it again!
Which are the best headers out there for 502mpi v-belt ??
just saw these : http://www.cpperformance.com/product...t-headers.htmc
#4
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I would use a good aluminum exhaust, Dana marine, Stainless Marine.. Even the new exhaust that merc uses on the the 496 and 502 base engines flow pretty good..
#6
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My father went with the Gil headers, plus the K&N mod. He had bought the Dana exhaust which I liked but had to return the Dana headers because the bolt pattern was not accurately machined/drilled. Left and right motors below (the blocks are now Dart 540 cu.in.). You might gain a few mph then you will need to sort out prop(s) (add cup or go larger) and have your ECU reprogrammed. The motors kept the Mercury 502/415 cylinder heads, mild cam, 87 octane motors, 520 hp on Innovation Marine dyno, 90-92 mph, no reversion.
Last edited by Smarty; 08-27-2013 at 10:07 AM.
#7
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Don't waste $$ on MSD. There are plenty of engines up to 800 hp running GM HEI ignition.
JRider is correct; your best bet is to look for a better ready-to-go engine and sell yours as an unmolested take-out...
JRider is correct; your best bet is to look for a better ready-to-go engine and sell yours as an unmolested take-out...
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Retired! Boating full-time now.
Retired! Boating full-time now.
#9
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I do not think your optimistic performance gain is realistic, maybe 200-300 rpms, maybe....someone on this board has made a similar mod to what you want to do, and will be able to give a more accurate answer. My reply is only a guestimate....