Do I have to remove the head to install studs? My head gasket is good and there is to reason to take the head off if I don't need to.

 

No real reason to if you do one by one. But bottom tap may be a P.I.T.A.

 

So I need to bottom tap the holes? Does anybody make a tap long enough?

 

I have been doing a bit of research. I have read that I need and extra long bottom chaser. I read on the internet (that doesn't mean it is true) that a tap can cut some of the existing thread making the block weaker.

So where can I find an extra long, 12mm, bottom chaser? I couldn't find a thing.

 

Nobody?

 

Talked to my Snap on guy, longest in his book is 6". Only thing I can think of telling you to do is buy a decent bottom tap then weld a piece of square stock on the end to extend it. You aren't really cutting new threads just cleaning all the soot and crusted oil out. I nearly ran mine in with my fingers and used lots of break clean and air pressure to blow the holes out, but my head was off being worked on.

Best I can help, I'd guess some one some where makes a stupid long one, but I'd think the above idea would work if you can weld decent. Also note I've only done this to my two engines not sure if some blocks aren't tapped to the bottom?

Side note; what studs you going with, and why you wanting to do studs?

 

I was thinking A1. I hit 40 lbs with my H1C on a retorqued head gasket (just once, it scared the daylights out of thinking the head gasket was gonna blow). I with be upgrading turbos and don't want to worry about my head gasket or mess with a waste gate.

 

Meh, I've been to 50 with way too much timing on stock bolts. But I understand your concerns. I've read some good stuff about extreme studs, I have not used them but will next time I need em.

I take it you weren't on par with the welding of a tap?

 

Does tool steel weld good or does it get brittle? I wouldn't want the top of the tap to break off making me pull the head anyways.

 

One possibility, what size is the hole in the head for the studs? Whitney tap extensions should be the ticket, a M12 tap runs the 1/2" tap shank, and the whitney extension for that is 9/16" body diameter, which works out to 14.3 MM, if you don't have to drill the head out to install 14 MM studs, it might just clear.

A thought at least.

 

You should use a bottoming tap and a plug tap to chase the threads, and lots of compressed air and brake cleaner until you are sure every bit of crud is out of the holes. Going through that drill right now on my truck.

 

So could I get a thinner 1/2" square socket and tack the tap to it?

 

Just a little info on taps from a Gunsmith point of view. I realize the taps I use are much smaller but they are very brittle...they are designed that way specifically so when you break one in the hole it is easy to shatter the remains and get it out of the hole.

Now does that cross over to the larger taps? I honestly couldn't say but I would be careful working that deep if you go that route.....don't force anything

 

Nope. If I were cheap, I would epoxy it rather than weld it, by the time you get to fusion temperature you are doing things to the metal that at best will make it unpredictable.

But the Whitney tap extensions are not terribly expensive, and you don't have to worry about any shenanigans.

Your call.

 

Does anybody know the bore of the holes in the head? Are they all the same?