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exhaust for 741 cam shaft whos running what

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Old 04-16-2010, 05:41 PM
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Originally Posted by fbc25el
The 139021 and the 139741 are two different cams. I am pretty sure the 741 has two degrease more than the 139021. They are both on 112 lobe centers.
I may be wrong but don't both have grind number (Z)HR-296-2S-12 IG? I tryed to compare the specifications in Engine Analyzer for 139741 and the cam card for 139021 and they seem to be identical. But again, I may be wrong.
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Old 04-16-2010, 05:57 PM
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So do you think i should re degree the cam to 107
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Old 04-16-2010, 08:00 PM
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If the ICL is in fact 107*, then yes. Do an OSO search on the 741 and I am sure you can find the recommended ICL.
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Old 04-17-2010, 08:02 AM
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The 741 is intake @.050 is 236 and the exaust is244 @.050. The 139021 is 234 @.050 and the exaust is 242 at .050.
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Old 04-17-2010, 08:10 AM
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Both cams have a sugested intake center line of 107.
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Old 04-17-2010, 08:25 AM
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Why was the cam degreed in at 111* rsstieny? The reason a hotroder might do that is to raise the hp curve. Thats fine on a car that has no water in the exhaust. Not so cool on a boat with wet exhaust. If you can get some exhaust inserts to work you can run it with no issues other than higher max hp rpm. It might perform great in fact.
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Old 04-17-2010, 09:33 AM
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Originally Posted by blue thunder
Why was the cam degreed in at 111* rsstieny? The reason a hotroder might do that is to raise the hp curve. Thats fine on a car that has no water in the exhaust. Not so cool on a boat with wet exhaust. If you can get some exhaust inserts to work you can run it with no issues other than higher max hp rpm. It might perform great in fact.
Ill try the inserts or go with different exhaust with dry tails ill let you know how it works out.

Thanks Rick
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Old 04-17-2010, 12:00 PM
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Originally Posted by blue thunder
If the ICL is in fact 107*, then yes. Do an OSO search on the 741 and I am sure you can find the recommended ICL.
X2 and I'm betting you have found the cause of your reversion.

Herre is a link to the cam card. http://www.cranecams.com/index.php?s...41&lvl=2&prt=5

You should also make more power in the RPMs need for a boat.
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Old 04-18-2010, 09:05 AM
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Originally Posted by Griff
X2 and I'm betting you have found the cause of your reversion.

Herre is a link to the cam card. http://www.cranecams.com/index.php?s...41&lvl=2&prt=5

You should also make more power in the RPMs need for a boat.
So you think i should re degree them in at closer to 107.
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Old 04-18-2010, 11:50 AM
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Originally Posted by rssteiny
So you think i should re degree them in at closer to 107.
Yes.
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