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Duration @.006 & reversion

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Old 12-18-2003, 01:01 AM
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Default Duration @.006 & reversion

If I increase duration @ .006 will I get more reversion.My last engine was a 454 with a 268/[email protected] & 224/[email protected] with a 110*LSA.This gave me 7* [email protected] am building a 502 now and the cam I have is 224/234 with a 112*LSA that gives me 5*overlap.The difference in this cam is the duration @.006 is up around the 290 to 300 range(I will degree it and get the exact duration).Will the new cam have more or less reversion???

Thanks Don
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Old 12-18-2003, 05:39 AM
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I think your new set up will still be ok but let some of the experts chime in on this and get their opinion.....Fred
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Old 12-18-2003, 05:45 AM
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Don, did the cam that you listed first give you any reversion? That is the one with the 224/230 @ .050....looks like it is the Comp Cam 11-242-3....the reason I ask is that I am trying that particular grind in one of my engines next, Fred
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Old 12-18-2003, 08:54 PM
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Hi Fred. You getting by in the cold, cold winter weather?
Dyno, SuperV, and a couple other guys over this way are running cams with 234/[email protected], .556 and .578 lift, 112 centerline without any reversion issues. SuperV has Lightning headers, Dyno has EMI Thunder.
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Old 12-19-2003, 12:33 AM
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Fred,the cam was the extreme energy you listed,and it did have slight reversion.I have stainless marine manifolds with the corsa silent choice.If I idled the motor and pulled a riser there was a slight bit of water in the manifold.I would give the motor a good blast of throttle at the end of the day before shutting it down to clear the manifolds.Never rusty plugs or milky oil.I should mention that this motor failed at about 2 hundred hours due to an exhaust valve failure.They were not inconel valves and I really don't know if the reversion was an issue.I am keen to use the cam I have with the large duration as I think it would be easy on the valves and seats due to the slower ramp speeds.Still debating wether to use the silent choice or turf it.I like the quiet option at the ramp.
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Old 12-19-2003, 04:12 PM
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HARRISONMIRAGE...did you set your 110*LSA cam up on 106*Intake centerline or 110*Intake centerline, the reason I ask was I was told to set it up @110* instead of the cam manufacturers 106* recommendation, Fred
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Old 12-19-2003, 05:52 PM
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Fred,I set it on 106.I had flat top pistons and small chamber vortek heads(aprox 9:1 compression).I would retard it a bit if you have higher compresion.With this setup I had about 180 PSI cranking pressure.Be carfull to use good fuel and don't over prop.I had a bad experiance with detonation by over loading a motor with a cam 1 size smaller instaled onthe 106 centerline.I tulipped the intake valves while trying too big a prop.
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Old 12-19-2003, 06:21 PM
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Try dry tailpipes. Problem solved.
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Old 12-20-2003, 08:47 AM
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What can I do to decrease the amount of water coming out of my tailpipes, I am running stock type center rise manifolds with cast risers....put a Y in the line to dump some off thru the transom? any ideas?....Fred
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Old 12-20-2003, 12:02 PM
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Fred,are you running silent choice,y-pipe or straight out exhaust.
Don
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