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Old 03-24-2011, 07:52 PM
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ok guys because of my recent motor upgrade i have to go to dry exhaust because of the camshafts in the engines .my motors are 511ci tall decks 9.5 comp. w merlin heads reworked by champion race heads. brodix hv intakes .950 holleys .and comp cams solid rollers 680 lift w a 106 lobe sep .the cam lobe sep is the bad .i have all new gil manifolds and dry risers .my question is can i plug the fitting on the pipe and drill 3 holes in the end to let the water dump as ive seen on others .im assuming the boat may be a little quieter and i wont have to drill the holes in my hull for the dumps .im just guessing at this but hoping it might work and still not pull water up the pipe as they are 42 '' long being a trs app .or maybe someone has a better idea or has been here before .ive added some pics of the pipes as they are now length and the 2 small holes currently in them

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Old 03-24-2011, 08:33 PM
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What you are thinking of doing is similar to mine. Dry to the tip. My cam is on a 108 And they sound wicked still. I have Gaffrig switchable tips over mine and the water helps to quiet them down.
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Old 03-24-2011, 09:03 PM
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You can modify them, but why?? Drilling the transom and plumbing for dumps is piece of cake. If its too loud, you can drill two small 3/16'' holes at the ends of the tails, and put some clamp on mufflers on.

Those old school long gil dry pipes sound sooo cool when completly dry!

Either way, even on 106* lsa you should be ok....
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Old 03-25-2011, 07:31 AM
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now im concerned.. i have regular bravo gills 112+2 lsa
duration 292 int/ 298 exhaust.

do i need dry? i really dont know alot about cam size
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Old 03-25-2011, 08:22 AM
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Originally Posted by STRAIGHTPRIORITY
now im concerned.. i have regular bravo gills 112+2 lsa
duration 292 int/ 298 exhaust.

do i need dry? i really dont know alot about cam size
If you can, post more up about your cams. Like duration numbers at .050.......
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Old 03-25-2011, 08:25 AM
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The holes you drill should add up the cross sectional area of the water dump fitting. If not, you might end up with a water pressure problem.
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Old 03-25-2011, 10:09 AM
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duration intake 230.0
duration exhaust 238.0
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Old 03-26-2011, 08:58 AM
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i hope i am ok
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Old 03-27-2011, 02:03 PM
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STRAIGHTPRIORITY - Those duration numbers on a 112LSA should not be any problem for reversion provided your exhaust system is not stuffed up with switchable exhausts run closed or little or no drop in height between the bottom exit of your risers and the transom tips exit height.

Best Regards,
Ray @ Raylar
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Old 03-27-2011, 05:58 PM
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i do have switchable mufflers.... do u think i should not use them? i was more concerned with running in rough water and commin on and off the throttles...
risers are standard gil tails with standard slope.
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