[Lightfoot]

Originally Posted by Jack Gifford

"Tapered valve guides"?

I wondered about the pressure suction to ventilate the crankcase.

Something tells me the advertising agent wasn't an engineer.

[Rich-Tripower]

Originally Posted by Jack Gifford

"Tapered valve guides"?

Originally Posted by Lightfoot

I wondered about the pressure suction to ventilate the crankcase.

Something tells me the advertising agent wasn't an engineer.

I was more confused by the "reverse flow gusher valve cooling". What?

[Jack Gifford]

"Reverse flow gusher valve cooling" is legitimate- that's what Pontiac called it in the shop manuals. Except that it's specifically intended for valve seat cooling, to allow non-insert valve seats (merely machine the seats into the cast iron of the heads). The coolant distribution tubes have holes aimed at the backside of each valve seat area.

But I've never a seen a Pontiac reference to "tapered valve guides". I wonder if the guide bores had a slight taper to assure that some oil would enter around the stem?

[U47]

Originally Posted by Lightfoot

I wondered about the pressure suction to ventilate the crankcase.

Something tells me the advertising agent wasn't an engineer.

That's what it is and that's why they called it that. It's also used in some automotive engine theory books. I think Oldsmobile has used the term.