extending stock risers
#1
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I've seen mention of it several times here on various threads, but never a discussion devoted to extending stock exhaust risers to increase the water introduction point. Does anyone have experience with this? It seems like an inner pipe extension could be welded to the riser elbow with a piece of rubber tubing over to create the longer water jacket. A baffle (reversion ring) could be fabricated on the new outlet end to further reduce reversion chances. I have GLM manifolds (small block chevy) and would like to go more aggressive with cam if I can find a solution for exhaust. I'm eliminating my thru prop, removing the Y-pipe, and installing side exit tips due to a low swim platform so I will have a 90 degree elbow close behind the riser. Does Imco have a riser that would solve this without buying a complete exhaust?
#2
Banned
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Corsa for 90's or whatever turns / bends and Merc or GLM extension riser blocks that fit in between your riser and manifold to raise the waterline height to aid against reversion.
#3
Registered
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First I don't see anyone welding to cast iron, next the flexible rubber tubing will not hold up and have other issues. To help with reversion adding riser extensions will help
http://www.mercruiserparts.com/bam/s...31954/7585/180
http://www.mercruiserparts.com/bam/s...31954/7585/180
#6
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Some of the elbow/riser combos from Merc for small blocks were stainless steel. Not all were cast iron. Second, a vertical component in the exhaust prior to water introduction does not aid much in regards to reversion. Water introduction as far away from the highest point in the exhaust will be the most benefit.
#7
Registered
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PS, the work I had done on both sets in the race boat was cheaper then one set of 6" extensions for the same exhaust and looks much cleaner.
#9
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Some of the elbow/riser combos from Merc for small blocks were stainless steel. Not all were cast iron. Second, a vertical component in the exhaust prior to water introduction does not aid much in regards to reversion. Water introduction as far away from the highest point in the exhaust will be the most benefit.
#10
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I'm not recommending you go dry either but the solution you seek with the stock manifold is elusive. I wish that weren't the case.
I'm just thinking out loud at this point but does anyone know if the Stainless Marine riser/elbows would bolt up? I don't think so but I haven't tried it.