Porting head...have a question (pics)

fastsc92

Registered User
OK i'm porting my spare set of head. I dont think i can do this, but i wanted to ask. Can i grind the valve guides down? They stick far into the bowls and it looks like you can grind them down and it'll make a big improvment. On the other hand...i dont want to screw anything up. here are the pics before i started, and the last few are after i did a gasket match. I still have to do bowl work and play around with the exhaust side.
433758_11_full.jpg

433758_12_full.jpg

433758_13_full.jpg

433758_14_full.jpg

433758_15_full.jpg

433758_16_full.jpg


After gasket match...(stock intake runner on the right)
433758_17_full.jpg

433758_18_full.jpg
 
From the conversations I have had yes you can remove the valve guide that extends into the bowl.


BTW: Are you really going to port the water passages or di you just mark everything off?:D :D

Aaron
 
what are you using to port the heads? A dremel/drill press? I might me interested in tearin into a spare set I got in the garage.
 
Looks good if you ask me thats about the same as I did on the intake I was able to pull 21 HP and 32TQ more with adding ported heads as well as a 5% pulley 76Maf. I can tell you I felt a a Big gain with the heads.

Good luck
 
i bought a porting kit from an online company. Its a complete kit with weird bits and sanding rolls. I'm doing much more than just gasket matching. I' doing bowl work as well as radius and gasket matching. The heads are going to compliment my Coy MIller cam that will be installed at the same time. Any more input about gringing that valave guide down to nothing??
 
I have seen lots of heads with the valve guides ground flat. I think there is a big advantage in raising the ceiling of the exhaust bowl which requires grinding the valve guide flat. My head builder however said that the gains in removing the valve guide that sticks down is not measurable and the extra stress it puts on the valve is not worth it. So after I ground the bowls the way I wanted them, he put new guides in.
Be careful around the valve guide in the intake bowl. You gotta keep the shape which creates "swirl" around the valve. If your dumping air in straight and the valve shuts, it messes up the momentum. But if you have a swirl effect, when the valve shuts, the air just swirls around the valve until it opens back up again and then it goes around the valve like a toilet flushing. Looks good so far.
Another tidbit of advice, I would not recommend opening the exhaust port at the gasket. It is already much larger than the bowl volume. The best thing on the exhaust would be to try to enlarge the bowl volume and even the velocity throughout the port.

There are also big gains easily had by unshrouding the valves. Just pop in some old valves so you don't damage your valve seats and lay back the angle of the wall which is currently shrouding the valves. Just make sure it's the same in each chamber and that you don't go outside the diameter of the cylinder.
 
alright...i'd decided to leave the guides in the bowls. I rather not risk anything. I'm just going to clean up the bowls, and the bowl on the exhaust side. I know not to port match the exhaust gasket. Thanks for the help guys, my cam came today so i'll take pics of the install and degreeing this weekend.
 
Hey, Fastsc92 can you give us a heads up on the kit you bought and the site for those who like to tinker? Thanks, Mark
 
i was told by Coy Miller that whatever i do...DO NOT gasket match the exhaust side. He knows these motors the best, so i took his advise and left the ports alone and worked on the bowls instead. Anyways, this is the site and the kit i bought. At the bottom of the page there is a "home" link. I didn't buy the kit from there, i did a search online and got it from a porting site called slickworks.com. They had the same kit, and many other kits at great prices. Do it yourself porting
 
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