Head log modification

[mannella]

Can anyone tell me if the log is cast steel or cast iron. I was thinking of cutting off the log and would like to install six motorcycle carbs. I'm a metal fabricator and making a plate to weld onto the intakes tubes wouldn't be a problem, but if the head is cast iron what to weld it with could be a problem as to what would work the best. Anyone done anything like this?

 

[gtm1086]

Cast iron

 

[Anlushac11]

Can anyone tell me if the log is cast steel or cast iron. I was thinking of cutting off the log and would like to install six motorcycle carbs. I'm a metal fabricator and making a plate to weld onto the intakes tubes wouldn't be a problem, but if the head is cast iron what to weld it with could be a problem as to what would work the best. Anyone done anything like this?

The log is cast iron and what you are describing has been done.

You can weld a plate on. A couple of people here have milled the side of the head off at a 90deg vertical from the head surface.

http://www.rickwrench.com/images-sounds/choppedhead.jpg

http://www.rickwrench.com/images-sounds/chop1.jpg

http://www.rickwrench.com/images-sounds/chop4.jpg

Some then drilled and tapped bolt holes to mount a plate to the side of the head for exhaust manifold and intake.

 

[mannella]

Has anyone actually welded to the existing tubes and if so what did they use. I didn't think cast rod would do the job well I have used 7018 in some cast welding Iron to steel but there was no stress involved.

 

['68falconohio]

I've used E309L stick rod for welding cast iron before, never on one of our cylinder heads though. It has alot more ductility than Ni-55 and Ni-99 stick rod. There are colloquial phrases to describe the hardness of the Nickel stick rods. :roll: The E309L welds weren't structural, just a stupid kettle that I got suckered into welding.

I used, IIRC, Inconel filler metal and TIG to repair an exhaust manifold for a diesel pulling truck. Not fast but it worked.

There's a company called Wisconsin Wire Works who makes some MIG wire for welding cast iron and other uncommonly welded materials. I used one of their wires(silicon-bronze) to MIG weld brass steam valves for a while. It ran really smooth. Stuff is pricey.

FWIW, I have a cyl head with the intake and exhaust milled off at 90* to the mating surface to block. I'm working out intake/exhaust ideas before I drill-tap holes to mount a 'mid-plate' that the intake and exhaust manifold will mount to. I thought I would be pushing my luck to make that much weld on cast iron without running into cracking issues. Chasing cracks in cast is horrible.

 

[mannella]

I've used E309L stick rod for welding cast iron before, never on one of our cylinder heads though. It has alot more ductility than Ni-55 and Ni-99 stick rod. There are colloquial phrases to describe the hardness of the Nickel stick rods. :roll: The E309L welds weren't structural, just a stupid kettle that I got suckered into welding.

I used, IIRC, Inconel filler metal and TIG to repair an exhaust manifold for a diesel pulling truck. Not fast but it worked.

There's a company called Wisconsin Wire Works who makes some MIG wire for welding cast iron and other uncommonly welded materials. I used one of their wires(silicon-bronze) to MIG weld brass steam valves for a while. It ran really smooth. Stuff is pricey.

FWIW, I have a cyl head with the intake and exhaust milled off at 90* to the mating surface to block. I'm working out intake/exhaust ideas before I drill-tap holes to mount a 'mid-plate' that the intake and exhaust manifold will mount to. I thought I would be pushing my luck to make that much weld on cast iron without running into cracking issues. Chasing cracks in cast is horrible.

I have always been able to weld cast, its the welding of cast iron to cast steel that has me concerned. I've never used a stainless rod for cast I have found that brazing on water pumps and such have worked well in avoiding more cracking. I have done some engine blocks with ni rod but never iron to steel.

 

[rickwrench]

Those shots above are of an early small valve head (C2, iirc), which had very round runners. The later large valve heads had larger, random shaped runners.

I milled this D7 head at an angle, avoiding the exhaust completely.

D7 runnners.

My original idea was a plate. With the early head, fitting MC carbs and a custom header would have been cake.
The late head... maybe cutting it at a 90 degree angle would have been better.
All became side yard ornaments when I picked up a 250/2V head.

Rick(wrench)