[hemi-jim]

My local, usually very talented machinist is getting his butt kicked by the guides in my 1986 N/A head. He's on the second set of replacement guides after having problems reaming the first set properly.

He says he needs to buy (or have made) .352 and .353 reamers to "step" the reaming to get to the standard .354. These sizes are not readily obtainable and will probably be an arm and a leg to have made.

I don't understand why he's having this problem. He's worked on lots of import vehicles before, including 944's, 911's, etc. and he's getting frustrated too. He says the guides shrink so much when he installs them that he has to do the "step" procedure, otherwise the .354 reamer is cutting too much material, it grabs and ruins the guide.

At this point, I'm considering going with an exchange head, since mine would still serve as a usable core. Any recommendations on companies that offer rebuilt heads (I know 944 Online does this for $495) or might be able to do the reaming (my preference) are appreciated.

Also, any thoughts on honing guides for clearance and/or final surfacing would be good to hear about.

Thanks - Jim