Porting the heads now...

[Paul Workman]

Porting my heads is NOT a project I had intended to be doing now. But, the bad valve made pulling the heads a necessity. Danged if I want to do it again anytime soon. Sooooo.....!

Had a problem on my first hole and ended up perforating the water jacket in one spot. (Gonna need some of Al's magic welding again!) The problem was not knowing how to index the axis of the hole, ended up blindly following the 35mm ball guide ever so carefully...right into the side if the water jacket...Dayam!

Marc Hiabeck told me I could safely cut .030 at the point directly adjacent to the cutout for the valve spring. So, to establish a reference for the (new) bore axis, I set my snap gauge for .030 bigger than the port diameter at the spot adjacent to the valve spring cut (located directly on the other side of the port wall - about 1-1/4" 'north' of the tip of the valve guide), and dished out a spot .030 deep. That point became the bottom reference point of the circle which would be the new port diameter.

The reference seemed to work like a charm! Best I could tell, the center of the port was a bullseye to the valve bowl. No more holes either (and that's a goooood thing!).

Looking down the runner of the head from the injector housing port you can see the centerline seems to be poifect!



The diameter of the top of the ports are (now) a shade over 37mm, and that's all I can tell ya less Pete breaks my arms or something! (JK) That is a 37mm ball (below), and ya kin see it goes down a bit more than "flush" too. (So much for the ol 36mm rule, huh?)



And, some smoothing and shaping of the inlet to the bowl (according to recipe), a little valve relief here and there, some minor exhaust work, and voila!



I'm on a quest to be ready for the Crown Point Corvette Challenge on Sept 26th. 500 ponies, give or take, would be a nice "perk" against the C5&6 crowd, wouldn't ya say? Wish me luck in getting it together in time!

P.

P.