I was just wondering who has done there own head work? Comp cam has a spring seat cutter for about $48. There valve guide cutter is about $46, and the arbor/pilot is about $20. These parts can be bought through summit racing. How hard would this be to do at home? Would you use a drill press or just a hand held electric drill? I know it wouldnt be worth it for only one set of heads, but what if I decided to tinker with a few sets. How many of you have done it?

If you just want to fool around and learn a few things it might be ok. I would be worried about measuements that have to be pretty dead on even using a drill press. Valve train is so critical. I'd farm that work out to a machine shop. They have the tools and experence to deal with it.

If you decide to tinker with it, please report back, I'd love to hear about it.

look at k line ( some where in michigan i think), i think they make better stuff. it's not hard to do. i've cut guides, spring seats, and stud bosses, but i have a mill so it makes it a bit easier

I've cut spring pockets and guides (to fit seals) on a couple of sets of heads. Used a hand drill and some common sense. At the time Isky would lend the tooling out.

RBob.

Yeah, a mill would be nice to have.
I will check out there line of tools also.


I just like doing things myself. I would rather learn how to do it than farm it out. I would practice on some junk heads to get the hang of it. If it turns out ok, I might do some work for some friends.

I just need to get more details on the tools.

Do the spring pocket tool bottom out, or can you go too far?
Same with the valve guide cutter?

Can I cut the spring pocket to a 1.55 and still use the 1.47 spring?

Also what about using guideplates? Would I still have to sent the heads to a machine shop for these. Depends on using the flat or raised one?

I may use a hand drill, but have access to a drill press.

For the spring pockets I placed a shim in the bottom of the original and then cut. Once the cutter hit the shim it stopped cutting. These same shims were then left in the pocket with the new larger springs.

The main purpose of the shim was to prevent the cutter from hitting water. IOW, the new pocket wasn't as deep.

Guide cutter stopped on something. Can't recall if it was on the top of the guide or on the spring seat. I'm thinking that it came down to the seat as the top surface of the guide could also be cut.

1.55 pocket and 1.47 spring: most of the time this works. It is the inner spring that holds center. You'll need to check this. But why cut the seats if not going larger? Or, just leave out the shim and use the original seat.

Guideplates: if converting from pressed to screw in studs a mill is best. Can do it other ways but they just don't turn out as well.

RBob.

Ok, that answered some of my questions. I wasnt sure how the cutters are constructed. Going too deep was my concern.

As far as how big to cut the seat, I wont the option of going from the 1.25 to either 1.47 or the 1.55. Depending on the cam and if I want to upgrade to even a bigger cam later.

Its just and idea that im kicking around. Maybe make some use of some stock Gm castings for a few projects.

As far as the screw in studs, I can tap the bosses myself. I may be limited on the type of guideplate, or may have to run without them.

I've cut spring pockets, stud bosses, valve bowls, and upper gude seal surfaces. I've done some by hand with a piloted tool, some in a mill, and some in a drill press. The mill makes it easiest to control final depth, but if you are very careful, you can use any method.

I've generally used commercially available tooling instead of the specialty cutters, but I'm sure they would work nicely if used at the correct speed/feed rates and with the correct coolants. I've actually had some of the best luck using piloted spot facing mills for most of the work - even with a large hand drill (for valve bowl cutting). You'd almost have to be a complete moron (like me) to screw that up The piloted mills are great if all the alignments are correct and all you want to do is alter diameter and/or depth. I can cut a spring seat in about five seconds - it takes longer to reposition the head for the next cut than to actually finish the spring seat.

For the stud boss milling, you could use a piloted spot facer if you are certain the stud holes are at the correct angle and you have a good idea of what final depth you want. I've had some challenges referencing the flat milled pads on the heads and transferring that to the stud boss surface for a depth indication. Every head casting seems to be just a little different in that regard. If you're not certain, it might be better to leave a couple of the pressed studs in place as a reference while you machine and fit the screwed studs and check for final depth.