[charlie66]

I wanted 1" but the guy that did it for me drilled it to 5/8 s . I would leave 1" if I do it again. U have to be carful on the end holes. If you go too deep you will run into the accessory holes in the ends of the head..

[slowbird]

Originally Posted by steve25

Does not anyone think that having 1400 degree Exh gases right on a Head bolt call for rethinking the clamping load that said bolt can provide?!
Also the Exh flame gets down to the Heads gasket area around that bolt and its not made to handle that.

I would machine down a 1/2" OD cast iron Valve guide to do the job if it where me.

Tons of heads out there with the head bolt exposed and no issues. Ford heads can have all 4 head bolts on exhaust side exposed

[v869tr6]

Originally Posted by charlie66

I wanted 1" but the guy that did it for me drilled it to 5/8 s . I would leave 1" if I do it again. U have to be carful on the end holes. If you go too deep you will run into the accessory holes in the ends of the head..

Thanks

[john marcella]

Originally Posted by v869tr6

Thanks John, looking at the 0.058" wall I was a little worried I would get the stud stuck in moly vs alum....would be ugly.

If you're not having head gasket issues, and the problem is just the material pinching in on the stud at the top of the register. Just put a hat washer in it and be done.

[v869tr6]

Originally Posted by john marcella

If you're not having head gasket issues, and the problem is just the material pinching in on the stud at the top of the register. Just put a hat washer in it and be done.

My head gaskets have been making a couple of years each, but after installing the hat washers the stud between the two exhaust won't stay tight, I can get a flat after every pass at 20 psi. I want to run more like 25 psi and know the cometic will fail if the studs don't stay tight.
New short block will have sealing rings but want to push my present combo a bit harder before the new short block go's in..

[charlie66]

I had no luck with the T-washers. Kept sinking an pinning the studs from coming out. There good for a situation with less heat involved I think.. The sleeve works ....

[v869tr6]

Well I pulled the center two exhaust studs and drilled 3/4" holes and then ran a holes saw at the bottom of the holes to flatten the bottom of the holes.
I didn't break into the exhaust ports! Won't be press fit but should work for now. Using 3/4" 0.120" wall moly tubes about 2" long.