Exhaust manifold pipe studs

[Lordsandy]

Just wondering if anyone has drilled and tapped new studs for the exhaust pipe and how it went?
Any tips? Did you have to remove the manifold?

[spec4don]

Your best bet is to take the manfold off. If nyour  going to drill it you need to stabilize it. if you try to drill the bit can wonder off and widen the hole out or drilling it out of position. Start with a small bit and work your way up. You have to look up what size drill to to use for the tap size. Also you'll need to figure out you depth.

The big issue will be drilling in the center of the bolt. Becareful when removing the manifold. It comes off in one piece and there are 2 hidden bolts by the center of the intake and exhaust manifold you can only see them fromm underneath.

Good luck Don

[Lordsandy]

Thanks for the reply.
I was thinking I would have to remove the manifold but know more studs will be broken and trying to avoid that if possible. Anybody know what the correct drill no. And tap I need to buy for the manifold studs?

[steve-0]

measurements for the pipe studs
7/16-20 SAE x 3/4 ~ 7/16-14 USS x3/4 Double-End Stud 2 1/4" long

7/16" stud by 2 1/4" long
7/16-20 threads on the nut side
7/16-14 threads on the manifold side
3/4" of the center section is unthreaded

part number au-ve-co 9705
http://www.clipsandfasteners.com/7_16_3_4_Sae_X_7_16_3_4_Uss_X_2_1_4_p/a9705.htm

7/16-20 brass nuts where used

http://www.google.com/search?hl=en&client=safari&rls=en-us&tbm=shop&q=%2B7%2F16-14+x+7%2F16-20+x+2-1%2F4+stud&aq=f&aqi=&aql=&oq=