Putting acc. hole in head?

[RingMaster4x4]

I bought a Serpentine belt setup my SBC and I need two more holes in the passanger side head. there are flat spots where there would have been holes. So the question is do you think it is ok to drill and tap two more?

 

[1979jimmy350]

how many bolts do you already have in the brackets if you have a good number in there already you will be fine leaving them out

 

[RingMaster4x4]

only one I am sure I need at least one more.

 

[1979jimmy350]

you could drill and tap the head but you need to be very careful not to break into the water jacket or even worse the combustion chamber. Just be carful not to drill to deep

 

[RingMaster4x4]

yeah I am only going to go 1/2 or less

 

[RingMaster4x4]

no one else has any word of waning?

 

[TJS]

You want the tap to be as perpindicular as possible. I think MSC has tap guides. A tap guide is sort of a bushing that is machined flat on both ends and allows the tap to fit through the bushing (with a little interference)and be used as a guide. I have made a couple on the lathe instead of buying them. HTH.
T.J.
www.tjsperformance.com

 

[HarryH3]

If the only thing behind the area is the coolant jacket, then you don't have much to worry about. If you get into it, just coat the bolt threads with Permatex before you install them. It works fine for the water pump bolts.

 

[PsychoticDeadGuy]

i think 1/2" is not deep enough to get a tap deep enough to have enough threads to really bolt and acc. bracket on...just my honest opinion

 

[RingMaster4x4]

let me find a picture

 

[RingMaster4x4]

ok the heads look like these the one on the left is the one I need to drill. my heads have two rased flat spots just like these off ebay.

 

[xpndbl3]

typically if you're interested in doing this type of drilling and tapping, i'd let a machine shop do it who has experience in this type of thing. Otherwise you risk drilling a bolt hole at an angle, or worse cracking a head.

 

[kgblazerfive]

Don't do it its not going to work. You probally only need one hole and you don't even need that. Never did it on mine and my serpintine setup has yet to fall off my motor. Read testimonies of guys who have tried and they want to know how to fix a leaking head.

 

[hero]

This may seem dumb, but why not just modify the bracket. Can you weld a piece of steel onto it that you could get to line up with one of your existing holes? That seems easier than drilling and tapping the head.

 

[RingMaster4x4]

the bracket is aluminum and there is only one hole on the passanger side head

 

[resurrected_jimmy]

I second this aproach why not make a bracket that you could take back to a manifold bolt even

 

[big4x4ride]

i drilled some holes in a set of camel hump heads that didnt have the accessory holes, wasnt a problem.

 

[jhellwig]

I agree with the guy above me. Several guys I have talked to have had to drill holes in heads that don't have accesory holes.