LocostUSA.com

I was looking through Youtube and stumbled across this https://www.youtube.com/@biy_buildityourself. Some enterprising young men attempting to build a double overhead cam V10 using a Ford Triton V10 block and cut and welded Ford Mod heads. I'm a little skeptical on it all working but it brought up a question that maybe one of you could answer. Welding the heads together would not seal the water jackets. Their solution was to seal the water jacket for each head section before welding the heads together and running the coolant externally. My question is could one partially tig weld the sections together, leaving sections unwelded close to the waterjacket and then aluminum braze around the waterjackets using the capillary action to seal around the water jacket? Like sweating copper pipes? Is that even a thing with aluminum brazing?

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http://www.lightningbugcars.com/

That's a lot of effort for a marginal improvement over the 3V heads that were available stock on the V10... But I won't argue the cool factor.

Without sticking it in a furnace, I think you'd have a tough time getting enough heat far enough in to seal all the way around with capillary action.

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-Justin

"Orville Wright did not have a pilots license." - Gordon MacKenzie

IMHO, it would make more sense and less work to make patterns from the two heads and sand cast.

I agree on the 3v heads.

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
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360LA 442E: 134.5x46x15
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Gibbs/Haynes:122x42x14
VoDou:113x44x14
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Agree that for performance, there's not much point. If a shop/YT channel is doing it, however, the attention and revenue may make it worthwhile.

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in agreement on effort to reward but all the other issues aside would oven brazing aluminum be a possibility for sealing the waterjackets?

_________________
http://www.lightningbugcars.com/

A one-shot, blind braze in an oven of a large, butted surface using a paste that is essentially silver solder since the melting temp needs to be much lower than that of the aluminum but much higher than the max temp of the head between cylinders (not coolant temp). Iffy.

_________________
Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

Aluminum 'brazing' rods are basically a very-high-zinc aluminum alloy that drops the melting temp to ~750*F. I think using those materials to oven braze, followed by heat treat, could work. However, to do it well is also likely easier said than done. So I would anticipate it still being a substantial, and not particularly cheap, effort.

_________________
-Justin

"Orville Wright did not have a pilots license." - Gordon MacKenzie

Follow up thoughts, the aluminum 'brazing' temperature is basically the annealing temperature of the aluminum. So while it would provide a reasonable mechanical joint between the two halves, you'd lose all of the heat treatment in your heads. The solution treatment required before aging back to a (typical) T6 temper would require taking the part up to around 1000*F for an hour before immediately water quenching. So the real question, that I don't know if anybody has ever answered, is even if the parts are fixtured together what would happen to the liquified 'braze' if the oven temperature is brought that far above melting point for a prolonged time and then water quenched? Perhaps the joint would be the same, or even better, but perhaps there could be some detrimental effects as well.

Welding has no such trouble with heat treating, and high-temp structural adhesives don't affect the base heat treatment in the first place.

_________________
-Justin

"Orville Wright did not have a pilots license." - Gordon MacKenzie

Heating the head to that temp would probably cause the guides and seats to fall out unless retained (without springs and valves) and the silver solder/braze to flow/fail. Another concern is the location of the head bolts that will be close to one side of the butted joint unless cutting across the center of a combustion chamber.

_________________
Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12