Valve Shapes

[DDRaptor]

i searched lightly and i don't know if anyone has posted this before, when it comes to aftermarket valves. What shape are they cause i want to ask if a valve could be milled down in the center of the shaft and then the metal can be return at the ends allowing more flow around the valve stem itself.

I got this from playing paintball since 2002.
here so VERY BAD paint pictures i just drew up of my idea.
http://i108.photobucket.com/albums/n19/DDRaptor/valve1.jpg
http://i108.photobucket.com/albums/n19/DDRaptor/valve2.jpg

[ghettogeddy]

its do able but what kinda strength are u gona be left with

[cygnus x-1]

That's what is called valve "waisting". Meaning the valves have a waist put on them. See this picture:

http://www.v8tuner.co.uk/products/large/pic547.jpg

A decent machine shop should be able to do it but for an A20 engine this would be probably one of the last few mods to squeek out that extra bit of HP. To make this even worthwhile you would already have to have done most of the other typical headwork kinds of things, including conversion to bigger valves. And it would only matter on a NA engine.

C|

[DDRaptor]

That's what is called valve "waisting". Meaning the valves have a waist put on them. See this picture:

http://www.v8tuner.co.uk/products/large/pic547.jpg

A decent machine shop should be able to do it but for an A20 engine this would be probably one of the last few mods to squeek out that extra bit of HP. To make this even worthwhile you would already have to have done most of the other typical headwork kinds of things, including conversion to bigger valves. And it would only matter on a NA engine.

C|


matter on a NA engine exactly what i want, but how durable would these be???

[MessyHonda]

yeah they would have to be balanced since you dont want to find a valve in your piston after you rev it to 7k

[Blkblurr]

You have a problem doing this because you loose the support of the valve guide and possibly the valve seal. You would need to look at the geometry of the valve and guide / seal design before attempting this

[cygnus x-1]

You would only turn down the part outside the valve guide. And I'm not sure if stock valves are strong enough for this or not. This is a question for Rich or a reputable machine shop that does this kind of work.

C|

[DDRaptor]

who's rich???

[MessyHonda]

who's rich???



the NA a-series king

[cygnus x-1]

Rjudgey. He is THE MAN for NA Honda mods. He's done more headwork on A20s that anyone else.

C|

[DDRaptor]

Ah yes so i guess i will be learning from him and openloops who supposed has a nice na setup.

[nskforlife]

although your idea would work, the velocity of flow would be minimal, you could gain more horsepower by using secrets with a dremel and each spark plug...

[DDRaptor]

please let me know you intrigue me, i have a brand new dremel kit eletric though buts that was inverters are for right.:)

[AccordEpicenter]

youd probably get better port flow numbers by grinding down the guides and fairing them into the top of the port

[cygnus x-1]

youd probably get better port flow numbers by grinding down the guides and fairing them into the top of the port

The intake ports are not too bad on the A20 but the exhaust ports have the guide sticking out a bit.
Here's what I did to the exhaust ports on mine:

http://bluegreenlabs.com/Prelude/Engine-build/FinishedExhaustPort2.jpg

I started doing the intakes but gave up because it wasn't really going to make much difference for my build.

http://bluegreenlabs.com/Prelude/Engine-build/IntakePort.jpg

If you really wanted to go all out you could fill in the area around the valve guide so that it's more contoured.

C|