I've often wondered if going with flat pistons (with the relief cuts, of course) would actually be doing more harm than good. I'm going to do a search to see if any discussions have been done on that, but it would increase the compression to about 9.5:1.

Future mod, perhaps?

At any rate, these mods look excellent!!

Not to self:

VERY spooky working on the valve bowls through the valve seat area. One little goof will scrap a cylinder head. Including being careful where the die-grinder and dremel collets are spinning. Selecting the right cutters and bits to be able to work the sides with the collet centered is very difficult.

If you just scuff a valve seat you may be able to re-lap them and have it work alright. If you actually take some material out of the seat area, just do a swap to bigger valves!

No scuffs yet, but I'm lapping them anyway.

I'm not looking forward to the other head. This is very difficult and tedious, not to mention stressful.

I would wish this on my worst enemy. Probably not you guys though.







Ok, maybe some of you.

I've seen the valves in the S1 firsthand...believe me, there is very little room for improvement in that area.

Does that mean you won't do mine?


I got the biggest valves that would fit, and they are barely any bigger. But they are undercut and swirl polished... so that helps a little, although the swirl polish effect will disappear after a while.

Stock heads don't make the best of the valve size they have to begin with. There'* alot to be gained if you're willing to take the risk on.

Off to get more brake cleaner to spiffy this cylinder head up. Rear head is done. Front comes next.

Some of these are progress pics, some are finished. Somewhat in order. Another reminder, working around the valve seats is SPOOKY BUTT-PUCKER ULCER-GROWING stuff.






















Tools, methods, dimensions, and techniques will be revealed at a later date. Probably around May/June.

Very nice Bill.

Real smooth. That has GOT to make a difference.

Not just smooth, but they're lighter now. A little material seems to be missing.