Need Some Tips On Shaving The Eyebrows On A 5hp Flathead

I Got My 5hp Racing Motor And I Need Some Tips On Shaving The Eyebrows And How Deep I Should Go?? I Am Also Only Gonna Port The Intake Port Out Cause Most Racers Say Thats All That Needs To Be Done

I'm no guru, but the mixture and gasses flow in both directions, which is why I did both ports. To be fair, I am eliminating the head gasket, which is equivalent to decking it by quite a bit. While this raises compression, it reduces flow in an L-head. The eyebrow job compensates for this.

In my logic, I needed to remove at least as much material as the thickness of the gasket I eliminated. I actually went slightly deeper than I had to, but I got a nice smooth level surface out of the deal, and STILL didn't get down flush with the valve seats. I removed a total of about 0.070". Just shy of that, really.



Suggestions? Yeah- use a dremel with a flex shaft, and TAKE YOUR TIME. Work slowly, and let the tool do the work. Don't apply much pressure at all, let the bit float. Think as if you're sanding, not grinding. I did most of the work with those little garnet sanding drums that go on the rubber cylindrical arbor. Use a straight edge to check progress off the deck, and remember to de-burr the cylinder liner after you do that edge. Don't go any deeper at the liner, than the top of the upper compression ring. The last thing you want is to hang a ring. Be incredibly careful not to hit either valve seat, and save lapping the valves until after this process is done. Do this only on a completely stripped down block, and wash the hell out of it after you're done.

Thanks For The Info On This. I Really Do Appreciate it alot

Anytime.

Tore Into The Motor And Figured Out The Block Has Been Decked 0

Oh? Got pics? What did you find?

Here Yah Go. Its Finished

Looks pretty good! Which method did you use?

I used a diagrinder with many different bits. Then took really fine sand paper and sanded some which brought it unbelievely smooth. Took my time and it worked great!!

Nice work!