David Floyd

Extrude Hone??? Worth it?

This is a cross post from the racing board, with some good info.

rage2

I have my intake manifold extrudehoned. Looks cool, not sure how much difference it made, since I did a whole lot of other stuff at once. Exhaust manifold can't be done because it's ceramic coated or something. Dunno what else to extrudehone.

Robby

I've heard good things about it w/other cars, like SVT for instance- they did the Contour's head, etc, and had great results, as have others. Not sure about it w/our cars, but have heard the same thing about not being able to do everything in ours, like Rage2 said. I guess you know what it is? It's when they take an abrasive putty-like substance and force it through the openings which cleans it out and actually makes it larger too. Anyway, no expereince or knowledge about using it w/our cars....

Silverbullet951

what exactly do you do when you extrude hone a car? I know it deals with the intake and opening it up, but what exactly do you do?

John Anderson

Our manifolds are just castings, so what happens when that putty finds an air bubble just under the surface in one of our runners? I'd tend to think it would gouge that bubble out, and then proceed to work it larger??

HOw would you be certain it would not have more of an affect on runner #1 since its closest to the input than say on runner #4 thats far away?

THe 951 intake manifold has sharply rounded deviders between each runner, will it wear that down? Possibly creating a larger more restrictive barrier for the air to travel around before entering the runners?

I'd have think, that the way the intake plenum on the 951 is shaped that the putty would bottom out against the flat side of the end of the plenum, slowing the flow to the 3 and even slowing it more to the 4 runner, forcing more from the 1 and then the two.

This is my thought, looking forward to more. Interesting thread :-)

David Floyd

I agree with John on the intake manifold, what I am going to have done is the turbine housing.
Garrett has tested with + results, so I will spend the $75, may or may not feel the improvement, but the flow is more efficient.

That's my reasoning anyway.

Mike S.

We Extrudehone to improve the surface finish of investment cast impellers we use in large industrial turbines we design and build. As stated, appropriate size abrasive media is suspended in a putty like substance and is forced under pressure through the part. Often the action is bidirectional (i.e. back and forth, oscillitory). Fixturing is devised to feed the part (from both ends when bidirectional). Adjustments to the pressure, "putty" viscosity, and media size are performed based on the geometry of the part and intended amount of material removal.

The questions John raised are very relevent and dimensional measurements before and after are the most effective way to understand where/how the material is removed.

For our application, the process is used to improve the surface finish of our impeller from around 125+ microinches to some where around 32 microinches. The process on our parts removes between 0.001 and 0.005 in of material. Tha material is aluminum. It is more of a polishing operation and not used to remove casting flash, parting lines, etc. It's important to recognize that without special approaches (plugs, vanes), you can't selectively remove surface imperfections without accepting gross material removal. Alternately, you can polish everything and accept that surface imperfections generally remain.

As usual, you can't have your cake and eat it too...usually.

Mike

SoloRacer

Rage: My stock intake manifold is off my car right now. I was considering getting it flow benched at some time. We could then get yours flow benched and post the gains for all to see. Sounds like a winter project eh?

rage2

[quote]Originally posted by SoloRacer:
<strong>Rage: My stock intake manifold is off my car right now. I was considering getting it flow benched at some time. We could then get yours flow benched and post the gains for all to see. Sounds like a winter project eh?</strong><hr></blockquote>

I can pull the manifold off after this round of tuning... sometime next week. By the way, are you selling your old block? I need one for my 2.8L winter project! =)

SoloRacer

Actually I was thinking of keeping it and possibly building my own 2.8 litre car. That way I would still have my numbers matching when I put it back in my car as my block has the 952 designation.