Selki

iTrader: (1)

So I keep reading about flycutting to ensure proper PTV. I know what PTV is and I think the accecpted is .080" int and .100" exh. Right? I understand that the process is to cut into the piston but is the piston milled down or is it just notched? What dose it look like after it's done? What dose the tool look like? Dose anyone have pics of the process or results? How do you know where to "flycut"?

I know that I can't be not the only one thats confused here and thare are alot of questions but if any one can explain it please do.

Beast96Z

iTrader: (21)

The process dos not require removal of the piston or any milling of the piston. You use a junk head with the seats cut out for proper alignment of the tool. The tool itself is just like a valve that goes in the head. It slides through the guide of the junk head, but the face of the tool is a cutter. You place the tool in the junk head and set it on the block. You then place a drill on the end of the tool that comes through the valve guide. You slowly start cutting, measuring your depth every few cuts you make. In the end, you just have "notches" that look just like valve reliefs in cast pistons. The cutters come in diffrent sizes, and you should purchase one that is larger than the size valve you are running.

Selki

iTrader: (1)

Thanks. Simple. Clear. And now I understand what it dose and how it's done. I thought it would be much more complicated than what it is.

Are there any draw backs to doing it such as weaking the piston? I realize that the cut can't be all that deep but is it a concern?

brad8266

iTrader: (23)

Anytime you take metal out it will weaken but flycutting will not weaken it enough to of major concern on a head/cam car. Now if you are spraying it can become more of an issue but if you are making that much power and using it enough you probably should eventually upgrade to a forged motor anyway.

Selki

iTrader: (1)

Thanks. I don't know if I will ever need to use this info but it's nice to finally know what it is. I figured I would ask though. I'm planning a H/C swap, TSP's PCR 2.5 H/C combo with a TSP Torquer v.2, and wanted to know just incase the issue comes up. The guys at Texas should be able to tell me if it's needed though.

Thanks again

tuffass

Dont think you'll have to cut w/ that set up. I've got the MS4 on stock heads and clearance is fine.

brad8266

iTrader: (23)

I wouldnt say that combo is "fine" on PTVC. Just becise it clears now does not mean its fine.