So my head may need to be welded because the detonation. The detonation marks on Cylinder #1 through #3 (#1 being the worst, #2 med and #3 very minimal) are right on the headgasket seal. He decked the head a bit and they’re still there and #1 will still be there when the head is decked to the max limit I think.
Anyone have their head welded before and how did it hold up? I track my car alot and am worried it may not hold up well?
I never heard of a head being welded!!.. best thing is to get a new one imo! Would u have a pic or can draw up something to show?!
Its not as bad as this but this is how it looks. Only 1/4 of the cylinder is like that.
Its on the exhaust side, where the headgasket blew on me/piston detonated.
The machinist said hes welded a few heads before and they’re still good. I think I’m gonna get him to weld it and test it out.
He tig welds it and then decks it clean.
what motor is this for?
It will more than likely crack again and again. Aluminum and stainless steel can be very hard to repair without ever seeing a crack again.
Especially if the piece is under high stress. Such as this.
I would be very weary of it. I would expect it to crack again. The welder and machinist may get lucky and it never cracks again.
I see aluminum and SS crack all the time. More often then not the piece is discarded.
SR20.
I’m gonna go ahead and do it.
What can happen if it cracks? HG blows??
^^ Good luck!!
sounds iffy, i’d personally go for new 
I mean its already gone through so much stress and wear, why risk something that is more likely than not, to break?
i’ve seen welded heads on SBC, held up fine… damage wise it was way worse
I have a spare SR head you can have for dirt…likely less than the machine ship would charge you to weld it. It’s an option if you want it.
Went to the shop to snap some pictures and tell Darryl the specs.
Limit on my head is 0.008" since my block isn’t being decked. He took of 0.007" so far. Here are the pictures. Hes going to cold tig weld it and deck it to 0.010" he hopes.
The head can be welded but it needs to be normalized afterward, then brought back up to it’s original hardness, otherwise it will happen again.
Are you sure this applies to aluminum, and not just to steels?
There would be no carbon (hardness) to play with…
just buy a new head. its safer
it can be welded. i have seen it done many times in jamacia at my cousins shop. BUT this is because it is nesessary. the down time and cost to replace the head is very high in jamacia. you don’t have this problem as sr heads are pretty common and realitivly cheap in canada. you just had a guy offer you a head for cheap in this thread. don’t risk it and just get another one.
peace
Hey Happy240SX, would you mind pm’ing me the details on that head?
If you’ve seen my rebuild thread in this section, you’ll see why.
I’m in need of some parts to say the least…
Sorry to thread-jack.
Aluminum has different conditions of hardness developed through heat treating just like steel.
I’ve had a few head welded before for a circle track race car. Never one for a turbo application though.
Providing it’s prep’d properly and pre-heated before welding it should be okay. If your still worried about the strength post weld heat treating is your best bet to make sure everything is back to speck (as mentioned above) then have the head deck by your engine builder again.
The head was welded on the milling machine. If the head was to be preheated in an oven then taken out and by the time it was set up the alum would have cooled down. Plus the cost factor of all that. Would then be way cheaper to buy a new head.
He ended up welding it and taking off 0.009" total. 0.001" over tolerance. I’m going to assemble the motor with the OEM headgasket and see if the valves hit by cranking the motor by hand. I’m currently looking for a thicker headgasket. If I’m feeling ballzy and the valves don’t hit free handing it I might slap the motor back in the car and see what happens since the car is done for the season.
Newfoundland dude, Dannos head is for S13 SRs. 
Welded aluminum changes state, the heat area looses it’s hardness, in this case a ‘T’ rating, it Will season back to a ‘H’ or half hard but it will be weaker then the rest of the head, normalizing then re heat treating will bring it back an equal ‘T’ harness.