Prepping Valves for Performance

[ZIPPY]

Hey all, long time reader here, but first time poster. I have found that the search button on this site has been one of the most valuable tools in building my Z.

I do have someting that I think might ad to the technical resources of this site. I also want you opinions on the subject.

 

Today I called SI valves trying to order their swirl polished stainless valves for the P79 head. JD from SI told me that those are a discontinued part and that no one else really makes swirl polished valves for the Z's. He said they could make me a custom set for about $30 a valve if I wanted.

Anyway I ordered a set of regular valves from them and decided to try my hand at performance prepping them. So far it seams that most people just chuck up the valve in a lathe of drill press and smooth/polish both its top and bottom. The intake only gets the bottom polished. Easy enough...

 

Then I found this article on adding "Powre Ringz" as the author calls them, to the intake valve. He claims that this helps with fuel vaporization and therefore promotes a better fuel/air mixture burn. His theory kind of makes sense I think, and might work like the "golf ball effect" to help gas flow across the valve surface.

Read it and tell me what you think.

 

 

Here's a link to the article.

 

http://www.allpar.com/fix/holler/valve-prepping.html

 

Here are the "Powre Ringz"

 

[ozconnection]

Firstly, welcome!

 

I've never seen anything like this before. I have seen a single groove or back cut on valves before however it was said to be not worth the effort.

 

I dunno about this one. I really don't see how flow would be encouraged into the cylinder as the valve curtain area has some of the highest gas velocities in the engine and those 'rings' don't look to me like they'll encourage 'flow' much. An increase in surface area they have but will this aid the engines performance?

Some sort of flow testing needs to be performed on those valves. Then an engine dyno is needed to establish power improvements and then chassis assessment to PROVE economy benefits.

 

Is it worth it?

 

Spend the money and let us know how you get on.

[kolonelklink87]

it does seem somewhat counter-intuitive to polish the valves and then "rough them up" again?

Perhaps the use of efi to promote ideal vapourisation somewhat negates the trade-off between flow and atomisation. At higher RPM I hear this can become an issue but combatable by moving injectors further away from the valves. This seems to be in the same territory as singh grooves... why not promote the same increases in atomisation by using a higher surface area intake manifold (if you're carburated and have this concern) for a fraction of the cost?

 

-pete

[DrSideways]

I hate the SSI valves aren't available anymore.

 

The thing I hate worse is the photo of the dude polishing the valve in a "high speed" drill press with his finger on the paper. I watched Jim Fitzgerald do this and take his index finger most of the way off. They could not save it.

 

Use common sense when around machine tools.

 

Alan

[pzofsak]

This strikes me as being similar to the concept of nucleation. I have seen this put to the test in soda and beer. The dropping mentos into soda and then it spontaneously releasing all the carbonation held within the liquid may be along those lines. Also, some beer glasses have laser etchings on the bottom to release carbonation into the liquid. Maybe this applies here, maybe not, but it is very interesting. I wonder if there is any more research to support this guys theory, or if it is just his best assumption.

[cygnusx1]

Maybe golf-ball style dimples would be better....Mythbusters?

[pzofsak]

mythbusters, thats where I saw the nucleation segment with the coke and mentos.