Putting 47mm Intake Valves in PI Heads?

[4.6LPoppy]

I'm new here, and just wanting to see if I can get better information here than the site where I have been. Hi.

I'm going to be installing some new cams and springs soon. I have PI heads which have been ported and polished (not CNC) and want to put in the 46.8mm stainless intake valves. So, do I need to do anything more than just have the seats ground and valves seated? I've been trying to read on it and can't find much. My machine shop says they only need the valves and the head and they will work. But what can he know....he works on Chevy's too. Anyone know? Thanks.

(If anyone here sees my similar post on another site, don't yell at me. I'm cheking this place out for a new home and to see if the info is better here. )

 

[CobraRed_96_GT]

i've had a little experience in the PI head machining world, and as long as the valve stem height is the same, you should not run into any problems as long as you grind the seats to fit the 3-5angle grind you have on the valves. Someone who does this personally may verify this, i'll tune in
- You're going to need new seals too

 

[4.6LPoppy]

i've had a little experience in the PI head machining world, and as long as the valve stem height is the same, you should not run into any problems as long as you grind the seats to fit the 3-5angle grind you have on the valves. Someone who does this personally may verify this, i'll tune in
- You're going to need new seals too

You said what I believe to be true. Just wanting some feedback here. The 46.8mm stainless valves are just SVO valves and are the same dimensions everywhere but the diameter. Sean Hyland says they can "replace" the stock valve. I think it is just grinding the seat to receive it with the multi-angle seat grind.

 

[4.6LPoppy]

Anyone done this??

 

[4.6LPoppy]

Anyone done this??

Guess not. OK.

 

[ACSPONY]

I don't see why you would have any issues. As long as the head is milled to fit the larger valve so it seats properly. If the valve stems are stock length, I wouldn't think you'd have any PTV clearance issues