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**breeh** · 07-03-2004, 01:10 AM

We are in the process of building a 68 396. The FelPro head gasket set that we have states that the block must have 3 lower coolant holes in the block or that they must be added if they are missing. We do not have the 3 lower coolant holes. Can someone shed some light on this as we are hesitant to start drilling holes in the block? Thanks in advance!

**breeh** · 07-03-2004, 01:13 PM

Nobody??

deth_1970 · 07-03-2004, 07:38 PM

I'm trying to remember, its been awhile, one way to get an idea, is to line the gasket up to the head, and mark with holes line up with the gasket, then do the same on the block, and take note of which holes are not present on the block, then go from there, I would tho suggest not drilling them free hand, but if you do, put rags into the cylinders, keep a tri-square handy, or try to make a guide for the drill to keep it straight,

*Randy70C-10* · 07-03-2004, 09:18 PM

Tap the center of the spot to drill with a center punch and drill a pilot hole first to ensure the your hole is properly centered.

**breeh** · 07-03-2004, 10:06 PM

Thanks for the feedback guys! It is not that I am worried about how to go about drilling the holes as much as the question of is it really necessary. From what I have been able to find out, only the early 396 castings did not have these holes. Was it a design change that GM made to improve cooling of the heads?

*Randy70C-10* · 07-03-2004, 10:10 PM

Are the coolant holes in the heads? If not then I probably wouldn't drill.

07-03-2004, 01:10 AM	#1
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	? for you professional mechanics We are in the process of building a 68 396. The FelPro head gasket set that we have states that the block must have 3 lower coolant holes in the block or that they must be added if they are missing. We do not have the 3 lower coolant holes. Can someone shed some light on this as we are hesitant to start drilling holes in the block? Thanks in advance! __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"

07-03-2004, 01:13 PM	#2
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	Nobody?? __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"

07-03-2004, 10:06 PM	#5
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	Thanks for the feedback guys! It is not that I am worried about how to go about drilling the holes as much as the question of is it really necessary. From what I have been able to find out, only the early 396 castings did not have these holes. Was it a design change that GM made to improve cooling of the heads? __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"

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07-03-2004, 07:38 PM	#3
deth_1970 Registered User Join Date: Jul 2004 Location: Braggs, okla Posts: 161	I'm trying to remember, its been awhile, one way to get an idea, is to line the gasket up to the head, and mark with holes line up with the gasket, then do the same on the block, and take note of which holes are not present on the block, then go from there, I would tho suggest not drilling them free hand, but if you do, put rags into the cylinders, keep a tri-square handy, or try to make a guide for the drill to keep it straight,

07-03-2004, 09:18 PM	#4
Randy70C-10 Account Suspended Join Date: Mar 2001 Location: Virginia Beach, Va. U.S.A. Posts: 15,320	Tap the center of the spot to drill with a center punch and drill a pilot hole first to ensure the your hole is properly centered.

07-03-2004, 10:10 PM	#6
Randy70C-10 Account Suspended Join Date: Mar 2001 Location: Virginia Beach, Va. U.S.A. Posts: 15,320	Are the coolant holes in the heads? If not then I probably wouldn't drill.



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