Main bolt sizes

[DieselNasty]

On my 12v engine I'm building I putting main studs in. Before I do this I'm going to make sure what size they are since they can be 12 or 14mm. Today I measured a bolt and the actual bolt was about 12mm but the threads were larger in diameter, the same size as an m14 bold I had laying around. So is it a 14mm bolt? Also said 12.9 on bolt head and was an odd 23mm.

 

[WUnderwood]

is it a STORM block?

 

[DieselNasty]

I dont know, how can I tell

 

[COMP461]

that is a 14 mm bolt, the bolt is back cut. If you want the proper stud kit its ARP part number 247 5402. I have 5 sets in stock if you need them

 

[DieselNasty]

Ok thanks Comp

 

[oldsmokey97]

that is a 14 mm bolt, the bolt is back cut. If you want the proper stud kit its ARP part number 247 5402. I have 5 sets in stock if you need them

Greg.. what ya mean the bolt is back cut?

Lance

 

[Texas Cowboy]

Anybody use 14mm A1 studs?

 

[Bobcat698]

Anybody use 14mm A1 studs?

Yes, I do.

 

[Bobcat698]

89-97 blocks have 14mm main studs.
98-02 have 12mm main studs.

 

[DieselNasty]

I was just about to order some arp 14mm studs from your site Bobcat. Love the site by the way, I can look at all the things I want and see prices on many things you usually have to call for.

 

[Tate]

Greg.. what ya mean the bolt is back cut?

Lance

They would be a waisted bolt, which is the shank is the same as the minor diameter of the threads, not the magor diameter like a typical bolt.

 

[smokin1997]

Anybody use 14mm A1 studs?

i do also now. along with other bottum end goodies.

 

[Texas Cowboy]

So do I. Was wondering how many others do.

smokin1997 you running a griddle?

 

[DieselNasty]

I also have a girdle

 

[smokin1997]

So do I. Was wondering how many others do.

smokin1997 you running a griddle?

yes. haisleys girdle.

 

[HRDROKN]

On the 14mm main studs.... anyone encounter the oil pan rubbing against the 12 point nuts? I'm certain that mine are touching the back face of the pan...

:what:

 

[JamieWood]

A1 Here!