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Discussion Starter · #1 ·
Is this done by simply beading up the intake and then grinding out a more uniform "D" shape. If so, is it done with a mig welder using aluminum wire or is it a special rod with higher silicon content for hardness? What amp setting are you using to get good pentration on the heads without putting too much heat into the intake and softing up the guide / seat area? Unless you are using a square wave welder that lays lots of metal down in a very short time so too much heat isn't put in to the heads. Just curious as to process that is used and how. Does it realistically increase your velocity over the short side that much?
 

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Otto is the only wrench in my area that I know of that does this. Believe he does use a MIG. You may want to get his attention and ask him but the shop is full and he is very busy right now.

Is this something you want to experiment with yourself?
 

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nw_guy4_fun said:
IMO for what it's worth MIG and aluminum castings is not prefered. TIG with straight argon and 6061 rod
Tig for sure. I think I would be pre-heating to 400 deg as well.
Just my .02 from years of melting aluminum the wrong way.
RB
 

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Just spoke with Otto, faulty memory here! he uses TIG with Aluminum rod but he said you could use MIG with a spool gun and special AC setup but he prefers the TIG for adding metal in cylinder head modification.
 

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Discussion Starter · #6 ·
Totenkopf said:
Is this something you want to experiment with yourself?
Not sure I would try this on a good set of heads but it may be something of interest that I would try on a ruined set. Mainly to increase my knowledge base and understanding of the process. I just have that type OC personality that meds haven't been able to control yet:wacko: Really its just that I have always had an issue to understand things that I don't.
 

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Road Bag said:
Tig for sure. I think I would be pre-heating to 400 deg as well.
Just my .02 from years of melting aluminum the wrong way.
RB

Yep, I've welded lots and lots of Shovelhead and Panhead heads to repair exhaust stubs and screw holes and so on. MIG would not be the preferred method. They really need to be pre-heated to 350-400 degrees after removing valves, springs, seals, etc. and then welded with TIG using AC and straight Argon and suitable filler rod. Not sure of the exact alloy of the late TC heads but this could be discovered then use a matching filler rod.

Square wave is nice if you have it on your TIG machine but not all that much faster.

Thiis sort of work is definitely not for the faint of heart.
 

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weldig heads

35 years welding here. 4043 is a good all around filler for aluminum. an argon/helium mixture (75-25) will give a hotter arc and get it done faster. tempil sticks will ensure even preheat. don't rush it! take your time.
 

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L-f-ant53 said:
4043 is a good all around filler for aluminum.
not an expert...but all the fixtures we build out of cast al. or 6061 is welded with 4043.
 

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nw_guy4_fun said:
Respectfully, there will be no JB weld in any of my motors, I prefer the old fashioned way, weld it

I certainly agree with this. Something nice about all metal in your motor. JB Weld has it's place, I guess, but not inside of your HD engine.
 

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When I had my heads ported by Bean, he reshaped my exhaust to a D shape. I know my builder thought that was a cool idea. Didn't even ask him to but the exhaust flow is like a tornado behind the bike up 15' away you can feel it pretty darn good on your legs. I didn't notice any welding or anything though. However way he did it it made a big difference on the flow of exhaust through, keepem sharp
 

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mig / tig

"Mig welding" is that done on a Russian jet? Automatic wire feed is not to good for welding cast. Tig stands for Tungsten inert gas.And is much like welding with a gas torch,only with a arc.
You must be carefull welding H.D. heads and cases they are made of a nonheat treatable alloy Do not get the parts to hot.It's ok to weld and make repairs as well as weldin ports.I will weld a small area then move to the other head or just let it cool for a wile as not to get the whole part to hot.
The D shape intake port hurts and helps If you don't raze the port at the same time it hurts because you have shortend the allready "shortside".Some grinders have mask this by makin a big port, now everything is slow.The shape and width of the short side are super inportant the secret is how the intake aproches the port.Remember the intake is part of the port/short side.D shape,w shape,oval,square they all can be make to work well some will work better (in a high specific output application) than others. Will a square hole flow more air than a round one? D shape and round?
Big Al
 

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For TC(UK),yes, JB in the exhausts on a Shovel worked real good. I'm too unsure to do intakes with it.
Did check the Mototune site; signed up!
Thank you,
Steve
 
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