Modifying And Welding a Cast iron head

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805moparkid

805moparkid

Slant and AFX Guy
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ok if you wanted to modify a factory cast iron cylinder head...

say you "sleeved" one of the ports...

how would you weld it up (or braze) so it would seal the port up??

the sleeve would probably be a DOM tubing

any idea's?
 
Dick Landy used to do a hell of a job reworking old heads with the port window raised to nearly the valve cover rail. The floor was welded to raise the bottom of the port.

This amount of work and result is something along the lines of what your thinking.

The thought of this idea would require a steel insert and welded accordingly, not brazed. The problem would probably be fitting in the boxed tube or more precisely, opening the head up that far due to the water jackets.

Go for it, let us know what you find and post up pictures!
 
rumblefish360 said:
Dick Landy used to do a hell of a job reworking old heads with the port window raised to nearly the valve cover rail. The floor was welded to raise the bottom of the port.

This amount of work and result is something along the lines of what your thinking.

The thought of this idea would require a steel insert and welded accordingly, not brazed. The problem would probably be fitting in the boxed tube or more precisely, opening the head up that far due to the water jackets.

Go for it, let us know what you find and post up pictures!
Click to expand...

yea im thinking of having the machine shop bore the correct size hole to just before the short side radius...

then press in a tube and weld...

and blend all the seams

so is it a big deal to have them weld it? i can do the finish blending...

also going for a tunnel port style O
 
I think you could do an interference fit ala cylinder sleeve, ice insert down and heat head up, press it in with some sealer and trim to fit. Or epoxy. Welding steel to iron?
 
pishta said:
I think you could do an interference fit ala cylinder sleeve, ice insert down and heat head up, press it in with some sealer and trim to fit. Or epoxy. Welding steel to iron?
Click to expand...

the first part was what i was thinking...

the second is what im worried about lol
 
ok well here are some pics of what i was thinking...

most guys run a 1.70/1.44 valves but the old rule i hear is the exh is 80% of the intake in size and flow SO a 1.8/1.44 should be perfect... the worm clamp is just over a hair @ 1.75"

now i made some slight changes to the chamber, trying to slim down the cc's and also smooth it some... THIS IS MOCK UP!! lol and yes that is caulking...

now for the tubing idea the ports are at a sharp and versus the deck

would i have to have the tube installed at that angle to help with sharp angles after install??

thx guys
 

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oh wow ok its for a slant sorry disregard my other post except for the epoxy part i would still use epoxy for the runners and just have it milled to close up the chamber
 
1qwikScamp said:
oh wow ok its for a slant sorry disregard my other post except for the epoxy part i would still use epoxy for the runners and just have it milled to close up the chamber
Click to expand...

well i want to stay away from milling the head deck surface if i do this head cuz it places the valves closer the cyl wall @ full lift ( hoping for .600 lift if this thing flows) so i will deck the block for better quench and have releifs made in the pistons
 
i know its not to scale but this is the idea
like red or blue??
 

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Well, it looks like a general straighting of the port AKA raised runners, is the goal. Like most serious performance heads do. And the cut away of the heads shows your water passages that the expoxy must seal up. The hardest part for sure.
 
One word of caution. After you have finished all of your welding be sure to have the head stress relieved. I learned this the hard way after building not 1 but 2 sets of Harley race heads, and having both sets crack in the very same spot. Finally a guy on Long Island who did work for Bill Jenkins repaired both sets of heads and gave me a short lesson on modifying and welding on iron cylinder heads.

Good luck with your project..............Ted
 
rumblefish360 said:
Well, it looks like a general straighting of the port AKA raised runners, is the goal. Like most serious performance heads do. And the cut away of the heads shows your water passages that the expoxy must seal up. The hardest part for sure.
Click to expand...

yea it will be tricky...

but im hunting for 10's NA from a slant

DusTed74 said:
One word of caution. After you have finished all of your welding be sure to have the head stress relieved. I learned this the hard way after building not 1 but 2 sets of Harley race heads, and having both sets crack in the very same spot. Finally a guy on Long Island who did work for Bill Jenkins repaired both sets of heads and gave me a short lesson on modifying and welding on iron cylinder heads.

Good luck with your project..............Ted
Click to expand...


can you go into more detail on stress relieving?

do they shot peen the whole head or something lol...
 
Exactly! Thats how they did my heads. I know that they spent some time in the oven but also they were shot peened.

Ted
 
The red angle you posted is what i planned on doing, it's a copy from a pic i saw in a '74 issue of cars magazine.

You braze in tubes and weld a flange.
 

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yea wild i have the same kinda thing going... i was just trying to keep it a little more low key than that...

more stock looking but i might end up just going for it... will see
 
What are you going to do for fuel delivery?Weber IDFs,IDAS?I love the idea.Look back at early pro stock.If it doesn't work,make it work.
 
Abodybomber said:
What are you going to do for fuel delivery?Weber IDFs,IDAS?I love the idea.Look back at early pro stock.If it doesn't work,make it work.
Click to expand...

i used to live in Los Osos... my dad still lives in Arroyo!

but for your question im making a custom intake with a carb for now...

i would like to got injected later as it will be a world record race motor...

hoping for 10's NA
 
bOb shingler said:
i think it would be better with rectangular tube pressed in because they flow much better but then again it's hard to drill one of those holes.
Click to expand...

i would think a round tube would flow better for a given port area due to no edges for turbulence??

but it would be another good test!

do they make any rectangle tubing with "soft" corners or would i have to just use normal rectangle tubing and weld/smooth the corners??
 
Good luck with the project. If you go with the angle of the red lines, will you have sufficient cooling for your needs? Are any mods needed to the cooling system?
 
Put the head in the oven @400 for 30 minutes, use a high nickel rod. tap any weld you can get to. Back in oven, turn oven off and let it slowly cool.
 
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