Help plz! Snapped head bolt!

[Olin]

I bought a fixer upper 2012 liberty jet 100k miles. Had a blown head gasket. Bought all new labor intensive parts for it because when in rome... Water pump, oil pump, oil screen, timing full rebuild(sprockets gaskets tensioners) thermostat and housing temp sensor the works and new head bolts. Everything came apart fine. No snapped bolts at all head or exaust. While torquing the new bolts in the 2nd head in the wack ass pattern last bolt snapped at 90 ft lbs. Removed the bolts and head. Its about 4 inches deep in the hole and about 1.25 inches left of the bolt. After 1 million dollars of drill bits i have a straight hole through the bolt. The problem is i cant find a easy out that is either long enough or an extension that makes one long enough. So me being me i pounded a socket on it and put a extension on it..... It snapped in the bolt... Stupid olin.... Got that out and threw away the cheap set of easyouts(easy my ass!) Now i have a helicoil set for a 12mm 1.75 pitch and a goid set of easy outs. My friend cause he is also a genius pounded a socket on the expensive easy out but faild to notice it was a 1/4 in socket.....smh we smacked it a few times into this demon bolt and tried turning it but it just twisted the extension and was about to snap. So should i go with the easy out on a 3\8 extension or just drill it out and use the helicoil? And it appears at least to me that the head bolts have some special threads on them? They seem a bit loose in a 12 1.75 nut and i dont think it should of been so hard to find a tap and coil of that size considering jeeps are simply great and the 3.7 engine was the worst ever! Should have been easy to find if thats the right size. And no it doesn't have the size on the box or website or anywhere i can find. Has zero info on the threads. My buddy is fed up and about to just set my baby on fire if i dont get it out of his yard... Sad faces pleas help an idiot out

 

[turblediesel]

Since you're in so deep and have the helicoil already you could just keep drilling it bigger and then use a tap to clean out the remaining bits.

Use left handed drill bits for those kinds of problems. Sometimes you get lucky and the goober just backs out.

90 Foot pounds seems pretty light to be breaking things off. Are these single use stretch bolts?