merc 15'' tuner ?

[merc326]

I just switched from a 20'' mid to a 15'' mid on my merc 260 and didnt switch the 20'' tuner, my question is, whats the stock length of the oval tuner for a factory 15'' mid application , Since I switched, my engine bogs a little when I first start to get on a plane, after just a second it comes to life and moves on. I figured the tuner may be to long and is submerged under water while ideling causing it to load up. Any ideas? Thanks
Merc326

[props4u2]

A stock 260 tuner from a 20" mid will work great. You need to drill two 1/2" holes in it for a better hole shot, 1 in each tube of the tuner, about 1/2" below the tuner flange on the inside front of the tuner


Lee

[THE FAST ONE]

<TABLE id=HB_Mail_Container height="100%" cellSpacing=0 cellPadding=0 width="100%" border=0 UNSELECTABLE="on"><TBODY><TR height="100%" UNSELECTABLE="on" width="100%"><TD id=HB_Focus_Element vAlign=top width="100%" background="" height=250 UNSELECTABLE="off">DRILL TWO 1/2 INCH HOLES BELOW TUNNER FLANGE.OF COURSE YOU HAVE TO REMOVE POWER HEAD TO DO SO,AS WELL AS TUNNER.--ED</TD></TR><TR UNSELECTABLE="on" hb_tag="1"><TD style="FONT-SIZE: 1pt" height=1 UNSELECTABLE="on">
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[Jay Smith]

I drill a 1/2" hole below the flange and after the hole is made angle the drill upward toward the powerhead, this allows the passing air through the tuner to form a draft relieving the air above the tuner exits and increases scavange....( the hole needs to be elongated so that the inside of the tuner has the hole slotted toward the exits and the hole on the outside of the tuner is higher, in other words the hole now works as a two sided sword , it will allow some pressure to escape when the tuner exit points are submerged, with the hole sloted will also then help scavange to boot, a straight cut hole only helps pressure relief NOT draft or scavange )

BTW : I never remove the tuner to do this procedure UNLESS I'm machining material off the tuner perch, no need in creating extra work...

this has worked for me for 14 years,;)

Happy Holidays

[THE FAST ONE]

<TABLE id=HB_Mail_Container height="100%" cellSpacing=0 cellPadding=0 width="100%" border=0 UNSELECTABLE="on"><TBODY><TR height="100%" UNSELECTABLE="on" width="100%"><TD id=HB_Focus_Element vAlign=top width="100%" background="" height=250 UNSELECTABLE="off">JAY IS RIGHT ABOUT NOT REMOVING TUNNER,BUT YA STILL HAVE TO REMOVE 1 P/PLATE WITH TUNNER ATTACHED.UNLESS JAY KNOW'S ANOTHER WAY.HOW IS IT GOING WITH YOU AND YOUR'S ,JAY? --ED</TD></TR><TR UNSELECTABLE="on" hb_tag="1"><TD style="FONT-SIZE: 1pt" height=1 UNSELECTABLE="on">

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[ProComp]

Hmm OK, how about going from a 20" to a 15" mid and just running a 2.4 200 powerhead. Should I drill these holes? I think I have a one piece adapter from a bridgeport with a bridgeport tuner. One side is 5" long the other is 6".
Thanks

[Jay Smith]

I'm peachy Ed, just bideing my time till retirement from EXXON ( 10 months ) weather was nice but has turned hot and humid again. I am absolutely COVERED up with motors....10 engines here now along with all the piece work coming in , but I'm chipping away at em but man its a chore....

Happy Holidays.......

[phooker]

Hmm OK, how about going from a 20" to a 15" mid and just running a 2.4 200 powerhead. Should I drill these holes? I think I have a one piece adapter from a bridgeport with a bridgeport tuner. One side is 5" long the other is 6".
Thanks

Damn. You are starting from scratch. I'm working on the Malibu too. Trying to see how loud I can make it. How's the 'toon coming along? Maybe the 2.4will fit on that? Gotta plan ahead.:eek: