[glhs#116]

Well, chaps.. I did do a bit of thinking along these lines myself, obviously. I was thinking, "gee, that column is probably there for a reason." But then I saw that it doesn't seem uncommon on other aluminium heads for other makes to go so far into the headbolt bulge that it's completely cut wide open. And these are high HP cars running high compression. I considered the deck thickness and how much meat was still there fore and aft and I reasoned that it must be fine. I do think it's probably fine. In the end I figured that probably the "reason" for the thickish head bolt column was to reduce production wastage in cases of core shift.

The other thing I considered was that porting-wise it was probably more significant than the pushrod bulge. That one just squeezes the inlet a little. It probably even has benefit at realistic power levels. But that head bolt one is just squatting there in the middle of the long wall turn that is trying to instigate the swirl. I'm aware it probably does almost nothing at low flow but I bet it's more significant as lift and throttle opening goes up.

Of course we all know that probably what happens at the seat interface and within an inch of it is the most important bit. Hopefully the small backcut and the smoothing on the chamber help a little there...

My head bolts are all ARP and they do use a largish thickish washer also. Anyway, I'll be sure to report back on any issues.

Sam