i went to bolt the head on my motor today. i oiled the threads on the studs and threaded them into the block. they're all over the place, some are threaded in a half inch further than others.

what size thread chaser do i need to run down the holes?

 

I had the same problem and had trouble sourcing the right thread size for the head studs so this is what i did and its FREE.

get one of your old head, (assuming you got your old ones still since you DID GET NEW new head studs like you should have, right?)

get a cut-off grinder with a thin fiberglass cut off wheel and cut 4 slots into the threads of the old head bolt that resembles a thread chaser

once thats done, clean it off any metal flakes and oil up your new "thread chaser" and "chase" the threads in the block.

remember to clean the chaser after every hole you do.

goodluck!

 

my old head, and the bolts that go with it are currently helping power the car....

i guess i'll go buy a new bolt at the hardware store and sacrifice it for the cause

 

I used a wire wheel like a bottle brush or a rifle cleaner in my cordless drill, with some brake cleaner, then compressed air to blow out the holes. Worked like a charm.

 

if you want i can ship you my "thread chaser" =P just cover the shipping cost which should be like 2 bucks

 

The head studs sit at funky heights. You drop the head on and suddenly they all look right - the heights of all the various holes in the head is different, and the block holes are deeper to correspond.

 

that may be true, but i dropped the head on, and there are a few suds where the nut wouldnt even touch the head if it was threaded all the way on the stud.

 

I think all are the same hieght except the front 2 are like 1/2" higher. But it sounds like you have another issue.