1CAMWNDR

iTrader: (21)

I am practicing porting on a pair of 5.3L truck heads. When I port the throats, do I take 90% of the valve size, the valve job, the valve seat or what? When porting the throat, do I also port the inside of the seat, or do I leave it alone and just open the aluminum throat?? I already have a 3 angle valve job on my heads so when I do them I don't want to tear up the valve job trying to port the throat.
Any healp is greatly appreciated.

Bo White

iTrader: (59)

There are tricks of the trade on that stuff so what I will tell you is what you should know starting off. 90% of the valve, so if your going 2.00" valve make the throat of the port 1.80". Realisticly though theres no set percentage on this when you start really splitting hairs to get the most possible out of a port flow wise...it just depends on port size/shape and valve size/seat angles/shapes. Its just not as cut and dry as one would like

1CAMWNDR

iTrader: (21)

OK Bo. Thanks. I have to thank you for the vast majority of tips for home porting my heads .