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I bought a Heavy Breather Extreme, for no reason other then I really like the look. So as per my usual routine, I drilled and tapped for external venting.
Starting with the internal vent passageways, I tapped the 4mm vents and screwed in some 4mm x 8mm set screws, using oil-resistant red loctite 263.
Drilled and tapped 1/16 NPT threads in the bottom of breather standoffs and used some SS 1/4" hose barbs and that red loctite again. Some black hose clamps and 1/4" fuel line too. Also filled the tops of the vents with JB Weld. I'm sure the red loctite will never move, but to me I'd rather not have the oil sitting on top of the set screws for all eternity...
More line, a nice chrome T from Lowbrow customs and a little Golan micro catch can at the end.
Only problem with the Air Cleaner is it's designed to work with both the 50 and 58 mm throttle bodies. But for some reason HD didn't think to include one of the neat little plastic adapters that they include with the Ventilator AC. I'm sure it makes no difference, but I didn't like the idea of that lip in there so I picked up 4 (to allow me to screw a couple up) of the 50->58mm plastic adapters.
Which don't fit of course. A few minutes with a dremel and voila, it fits.
Slipped it on and good to go.
Going to mount it up later or tomorrow. May eventually just run a hose from the T to a real catch can mounted somewhere, but the little Golan will probably be fine. I'll open it up every few hundred miles and see whats in there.
Looks good. I have the other style Heavy Breather with the snorkel style filter setup (not the one piece like yours). Mine didn't come with the chrome cover attached to hide the black box so I bought that separate. When I pulled it all apart to mount the cover, it wasn't that bad inside the breather ports but there was some of the coffee colored crap in there. Got me thinking of doing the bypass at some point, just have to figure out a way to do it so that it doesn't look too out of place and without having to cut that cover to hell lol.
Looks good. I have the other style Heavy Breather with the snorkel style filter setup (not the one piece like yours). Mine didn't come with the chrome cover attached to hide the black box so I bought that separate. When I pulled it all apart to mount the cover, it wasn't that bad inside the breather ports but there was some of the coffee colored crap in there. Got me thinking of doing the bypass at some point, just have to figure out a way to do it so that it doesn't look too out of place and without having to cut that cover to hell lol.
That chrome cover is actually part of the entire backplate. Pita for my purposes, though a nice design. I'll snap a photo so you see what I mean.
That coffee colored crap is oil mixed with water. I don't want my motor burning that, regardless if some say it's perfectly fine.
I did it to the standard heavy breather like you have. The trick is having a drill press. You need a straight hole to tap and I can't imagine doing it by hand on a curved piece of metal.
Right. The way my cover and backplate fit together is close to the same as the 1 piece look. I'm wondering if there's a way to hide the breather bypass a little better with that cover. Doesn't seem to be though as you can't get at the bottom of the backplate breather ports very easily.
Last edited by Cygnusx51; Mar 14, 2017 at 08:08 PM.
Right. The way my cover and backplate fit together is close to the same as the 1 piece look. I'm wondering if there's a way to hide the breather bypass a little better with that cover. Doesn't seem to be though as you can't get at the bottom of the backplate breather ports very easily.
I thought of maybe routing the lines under the cover but there's just no room with the throttle body and the servo.
Originally Posted by Dr. Tiki
Nice! I want to do this mod as well but I haven't figured out a way that I comfortable doing myself yet.
It's easy enough as long as you have the tools. Tapping the vent passages is easy, just need a 4mm tap and some set screws (4mm for this air cleaner. The standard heavy breather and the ventilator use 6mm) Drilling the holes for the hose barbs is the only challenge, as I said, you really need a drill press.
I got everything from Amazon, including the drill press ($60 if I recall) - definitely not contractor quality, but for the limited use I give it, perfectly adequate.
Yeah that's what I was figuring, not much room at all to work with. I guess if I used some stainless braided hose it would blend in pretty good though.
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Another Air Cleaner external breather mod...
