To all you guys out there doing head work: Since you have to really Bust your a$$ to get them out in the first place, you should get them over to a A1 class automotive machine shop, have em glass peened, boiled, and all valve quides, valves, springs, keepers, and stem seals and NEW HEAD BOLTS CHANGED. If they magna flux there, have them check for combustion dome cracks. If you have cracks in the domes, you'll need a different head to RB. Your original head bolts are already stretched, and are no longer able to maintain retorquing specs. The shop must also provide the 3 angle valve grind in conjuction with the new valves, as per original OEM spec, with accompaning hand lapping and leak down testing. Its also certain that the flat mated surface of your original head is going to be somewhat warped, thats guarenteed. So a final flycut of hopefully a few thousands will insure the heads flatness. Grease the NEW head bolts with Bostick anti-seize, and do the old 3 step torque-down and recommended sequence tightening procedure. If you do it this way, re-torquing isnt necessary. A new cam chain wouldnt be a bad idea at this time, you could probably fish it through and use a stakeable master link to connect the new chain up again. Under no circumstances allow the machine shop to supply their own guides, as OEM guides are a very special alloy probably (nickel-silicon). Even though you might spend much more for the new valves and OEM guides, ITS WORTH IT, as its better to have a new valve than one that goes south due to micro fissures, and eats up a piston and cylinder. Buy all the parts ON line if you want to save the bucks, and only OEM. (www.*************** is the least expensive so far) If you have a few bucks more left after all this, do all the rubber parts that are around the intake manifold including the 2 big idle solenoid bypass hoses. This information comes from 30 years of RB'ing my own and friends, cars and bikes, and its a crying shame that if you skimp just a few bucks on any item just mentioned to do this kind of work, quess what? That heads coming off again, from something you missed.....
Dont forget a OEM MB head gasket, Ive seen some after market ones out there, FERGETABOUTIT........
PS: Its critical you dont over flex all your original wiring harnesses to sneak that head out, the wiring insulation is most probably very brittle by now, and you will only create total havoc, if you arent careful. By cracking insulation here and there, you will be creating shorts to all your sensors and modules. Take a deep breath and good luck.....
Dave R.