Thanks for the heads up... I was going to buy one this weekend to play around with.

I bought three. One for a friend, two for me.

Took almost 7 weeks to get them. First one out of the box doesn't work. Haven't tried the other.

Ahh... now, I wouldn't buy anything from HF if it wasn't for having one 5 minutes away, where I can return something if (when) it turns out to be a piece of crap.

Impact wrench - broken w/in the first 10 minutes of usage. Replaced within the first 30 minutes of usage. Absolutely useless to this day, though it 'works'. Air ratchet? Actually, very good experience with their 'professional' 3/8 - it'* a beast (as long as you keep it oiled).

Maybe I'll still pick one up this weekend, and writeup a quick comparison to the other dremel type tools I've got laying around...

My first one didn't even spin. Totally dead. Essentially a plug on the end of my air hose.

Not even a hiss.

OK here is a URL to explain what I'm asking. http://www.kc2jga.com/photo.htm . Why would I have to remove heads to do this. I guess my questions are:
1) should I "smooth" out all the ports while I'm in there porting anyway? and

2) what are the benefits?

OK last comment and then I won't post more on the subject. Basically you drop a gasket on the LIM. Trace it with a sharpie, and then stay a 1/16th away from the outer edge of the sharpie so as not to leave a "shelf" at the head. Is this correct? I also know to stay the h*** away from the injector port.

They were only saying you'd have to remove the heads if you choose to gasket match the set. Basically, you don't want to remove too much material from the LIM, because if you make the openings larger than the corresponding openings on the head, you'll be creating a lot of turbulence in that area. In text graphics, it would be something like this:


<edit> egads, that didn't format correctly!! replaced with awesome word grapics!!

Well, my text graphics suck, but the point is, if the difference in port size is too large, bad things happen. So they say to keep the LIM to the size of the ports on the heads, else you need to remove the heads to clean them up a bit (because you don't want all of that crap to stay in the head, and find its way into the cylinder).

And smoothing the ports should help, but not in the large plenum area, as the air is (more or less) static in that area.

This is what we were suggesting Head removal for.

On the pics you linked to, it'* hard to tell, but those ports look too large.