63 SB engine

[Rainer S.]

I have a SB 327, 360 HP engine in my car. On the front, top of the block, almost center , there is a hex (for an allen wrench) 1/4 NPT plug. Someone told me that the plug is incorrect. Is that so ? It may have been replaced by the engine rebuilder...

Rainer

[Dennis C.]

Rainer, Believe that is usually a male square...

...pipe plug - however, I thought the thread was 1/8" npt, not 1/4".

[John D.]

Re: 63 SB engine

Ranier, As Dennis said the plug is 1/8" pipe. But the head of the plug is square. Those plugs readily available at NAPA although the new ones don't have the slight recessed head of the old original. In any case it's not an allen screw. I don't know the purpose of this plug. But it's an easy way to spot a Flint engine from a Tonawanda one. The T's don't have the plug. Plug painted orange of course.

[Joe C.]

Re: 63 SB engine

Plug is for a test hole drilled into the oil gallery.

Joe

[John D.]

Re: 63 SB engine

Joe, Thanks. Haven't heard that answer for a long time. John

[John H.]

Re: 63 SB engine

Flint V-8 drilled the front oil gallery junction from the outside, and that's why their blocks have the hole and the plug. The Tonawanda process to create the junction was different and didn't require the external hole.

[Rainer S.]

Re: 63 SB engine

You are correct, that is 1/8" NPT. Will have to replace the plug. Thanks for the ic and comments..

Rainer

[John D.]

Re: 63 SB engine

John, One time I caught a guy cheating. He put a plug in his Tona block. He didn't know the spacing was different on the ribs. Also he didn't know that the block he counterfitted had a clock on the rear. It was pretty funny. John

[Robert Willis]

Re: 63 SB engine

I saw that hole used for oil pressure to and air compressor on a dump truck of early 60s vintage. Test hole or an extra oil feed, other than Corvette ???

Bob

[Mike M.]

Re: 63 SB engine

agree with bod as we had an old chevy dump truck with air brakes that utilized the site in question to lubricate the air compressor.mike

[Robert Willis]

Re: 63 SB engine

In 1955 the 265 used the same oil pressure location was used to feed the remote oil filters on passenger cars. I think the filters were to tall to clear the Corvette hood.

Bob