Cracked head

Obvious, looks to propagate from the stud hole through the water jacket and move between the center.

I would tend towards brazing this instead of welding. two reasons 1) welding will likely propagate the crack further and 2) warpage in the center of the head.

Find the end of the crack and shallow drill a 3/16" hole, then taper grind the crack out to the stud, preheat the head to 330 to 400°F and then braze from the drilled hole out to the stud.

Finish with files and check head for flat or better, mill 0.010" off.

This is what I would do, others may have other/better options.

Thanks for your comments Gman and Frank.

Fortunately, if I needed a replacement head I would be able to find it here with the contacts I have and some friends.

No real need to try to get a head from the US.

Putting a VAM 282 head on an American 258 has been done, you have to modify the engine block due to the larger combustion chambers. The Mexican valves will hit against the block walls due to the larger diameter, you have to make a space for them to move freely in their whole run.

I would consider a 4.0 head but not in this car, I'm keeping this one mostly original. Maybe another VAM project car in the future will do. The only changes I've made so far enginewise are the distributor (HEI), alternator (70 amp with built-in regulator), the pistons (flat) and the exhaust (from single to dual). The rest of the engine is virtually stock original (carburetor, intake, headers, head, camshaft, crankshaft, cooling system).

Something I have been very curious about is to compare the 1982-1983 VAM head with the 4.0 head. The 82-83 VAM has all-new rounded out intake ports and have the best flow of ALL VAM heads produced. Unfortunately we still don't know if this head was ever tested horsepower-wise. The VAM 282 with this head would go from 129 net horsepower of the previous design to AT LEAST 135 net horsepower with the 82-83 one.

It would be very interesting to make a test of how the VAM head would fare against that of the 4.0 head, but so far I have not been able to find a head of this period.

The valve sizes may not be the only difference. Combustion chamber size may be different as well. But a US spec head will bolt on and the car will run flawlessly -- with a little more or less poser depending on combustion chamber size and how that affects compression. The valve size difference won't be noticeable in normal driving, but would affect high rpm power output. It might make 150 hp instead of 170 at high rpm, but you'd never know it under normal driving because you seldom run the engine at high rpm.

If available I'd go with a 4.0L head if I needed to change. Even with a bit smaller valves the head flows better than any 258 head, even one highly ported with larger valves. Ports just have a better shape, don't need to be huge. 

Thanks guys,

Fortunately, I have been recommended of reliable service shops around my area that can fix the problem, as soon as I have the head with me I will take it to them and check what the actual price would be to have it fixed.

I hope I have the money available with me.

Fortunately, I do have another head with me, which is currently on the car, allowing me to use it until the main head is finished and ready.

American heads won't work since Mexican heads have different specs, mainly larger valves both intake and exhaust.

As soon as I have the head with me I will take pictures of it and post them here.