cmi vs gill w/silent choice
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cmi vs gill w/silent choice
Hey all, what's the hp diff between the 2. Say I had a dyno of 600hp with cmi-& then switched to gill......same or what's plus/minus
#2
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I too would like to know, if you gain any hp with the E-Tops versus the Gils, or is the hp gain negligible, or do you need to go the full length sport tubes to gain hp? Have any of the engine builders on this board tested (dyno) the difference?
Good question, Paintman...
My $.02 opinion, I would think that the E-Top and Gils wopuld produce similar hp number for your example (600 hp engine). The sport tube (longer runner length) would produce more hp, at a higher cost too ($$$).
Good question, Paintman...
My $.02 opinion, I would think that the E-Top and Gils wopuld produce similar hp number for your example (600 hp engine). The sport tube (longer runner length) would produce more hp, at a higher cost too ($$$).
Last edited by Smarty; 05-29-2010 at 09:02 PM. Reason: spelling error
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hey smarty thanks.............i was "told" that the gill would be 50hp less............. i switched from the etops , wanted the silent choice but if there is that much hp diff maybe i should have just added the mufflers
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My father (this was his boat and motors) wanted his 540 cu.in EFI motors to be mild, and run quiet, and hp was the trade-off with the Gils, but I would think Gils would last longer than welded headers ( he worried about cracked headers with the CMI's). I am not expert, so maybe the more experienced OSO brotheren will comment.
Last edited by Smarty; 05-30-2010 at 03:54 PM.
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Myth Busting
There was a test on here some time ago where an engine builder did some head to head comparison....not sure if it fits all your criteria but some at least....
Click on the "View High performance Projects" in red on left side...
Next click on top link "496 Mag Dyno Testing......."
http://www.fullthrottlemarine.com/
Click on the "View High performance Projects" in red on left side...
Next click on top link "496 Mag Dyno Testing......."
http://www.fullthrottlemarine.com/
#7
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No way it will be a 50hp. Maybe 10-15hp. I switched from Gils to CMI's on my 525SC and saw no difference at all in top speed.
Make sure you don't have reversion issues if using the short silent choice risers.
Make sure you don't have reversion issues if using the short silent choice risers.