That is the question. My cousin ported my 416 heads off of a 305 for me a while back. I am going to be running them on a 350. I have some nice stainless valves (1.94 and 1.5) that I could put in but would it ruin the porting on the intake side? I think the exhaust side is the same size so it would just be a valve job there. Would it just simply be blending the top where the hole was larger down to the rest of the bowl? If that is the case I think I could probably do that without to much trouble. Unfortunately I will have the 1.84 and 1.5 valves in there for a while because I just want to get the car back on the road but just was wondering what I would have to do in the future if i pull these heads back off to upgrade the valves.

Ben

 

I would think it'd be OK. You're only talking about .1" of difference in valve size, ya know?

Trying to remove just that much may cause you to accidently hit the valve seat, so I'd do it BEFORE the seat is cut.

The rule of thumb is 85% on the intake 90% on the exhaust. If it's near that, I wouldn't worry about it. Just check them with an inside mic first to see if it's worth the trouble.

Good luck

 

So you think I should just have the valves put in ad be done with it? Do you know If it is possible for them to bore it or whatever they do to put larger valves in and then I would get them back to do any porting I wanted and then have them do the valve job? If you guys think I would be fine just haveing them put in and leaving the porting as is I may do that. I was just basically wondered if I would be loosing some of the potential of putting larger vavles in if I didnt do this?

Ben