Seating new valves?

[Z34Phoenix]

Ok so my ported heads are getting close to being done. i have a set of new valves i am going to install. i know they need to be seated, so i bought Permatex Valve Grinding Compound. I have seen on some videos that you use a tool that looks like a stick with a suction cup on it to spin the valve back and forth to grind it to match... my question is can i use a drill? or where can i get this stick and cup thing. is there anyone that has done this that can offer pointers?

 

[TEK310]

the point of that compound is to verify you have a full seat between the valve and seat. it doesnt seat the valve.

your shop should be doing this.

i just got done finishing my own heads, i work at a machine shop.

the process is, grinding the seats, to the angle specification, being your valves are new you wont need to grind the valves.

you shop will lap in the seats with the compound to verify the valves seat completely.

 

[matt5112]

apparently lapping the valves isn't needed as long as the valve job was done properly.

 

[TEK310]

correct, but its reassurance and gives you a visual of how well the seat is between the valves and seats.

 

[siLversLeigh]

Lapping isn't a very accurate way to check the valves, prussian blue is the correct way.

 

[WACHS]

Ive used tranny fluid to see if theres any sepage past the valves. Just had the heads done on my L67 build and did this. I got a few drops get by on the exhaust valves. I didnt bother relaping figuring on a street car, daily driver, it would be noticed.