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enkeivette · 07-09-2012, 09:43 AM

Theres talks on the interwebs that cams with more than 230 degrees of duration can have 'reversion' issues and theres danger of sucking in water. (Boat apps) This sounds like a load of bs to me, what do you guys think?

First of all, duration AND lobe sep angle come in the play with overlap. So a cam with a 110 lsa and 232 degrees of duration would have about as much overlap as a 114 lsa 236 degree cam. So a static rule like that is retarded.

Secondly, for the exhaust to suck in water, that tiny little bit of overlap is going to have to overpower the other 3 cylinders in order to actually suck air in all the way from the collector. Sound theoretical at best and realistically impossible to me.

Thoughts?

07-09-2012, 09:43 AM	#1
enkeivette Super Moderator Join Date: Dec 2007 Posts: 6,850 Tweet	Reversion Theres talks on the interwebs that cams with more than 230 degrees of duration can have 'reversion' issues and theres danger of sucking in water. (Boat apps) This sounds like a load of bs to me, what do you guys think? First of all, duration AND lobe sep angle come in the play with overlap. So a cam with a 110 lsa and 232 degrees of duration would have about as much overlap as a 114 lsa 236 degree cam. So a static rule like that is retarded. Secondly, for the exhaust to suck in water, that tiny little bit of overlap is going to have to overpower the other 3 cylinders in order to actually suck air in all the way from the collector. Sound theoretical at best and realistically impossible to me. Thoughts? __________________ I <3 forced induction.