Opinions on having the turbo exhaust finns clipped

[AudiVWguy]

I'm trying to do some research on clipping the exhaust fins on a K-14 turbo. Been doing some reading, most stuff found about gasser turbos. A lot depends on the application and the turbo. Basically, by clipping the exhaust side fins, you are creating less blockage for the exhaust to pass through. And of course there is a down side, slightly slower spooling. The amount of metal taken off is rated in percent (of the entire wheel, I guess) 0 to 15 percent. Meaning your turbo guy might recommend a 10% clip.
So, since the K-14 spools so fast anyway, and at higher boost and full throttle acceleration, this would relieve some of the bottle-neck restriction reducing the turbo's EGT'S. I read one diesel application where this lowered his exhaust temps 150-200 degrees.
Has anybody have any knowledge and/or experience they can contribute?

[RadoTD]

That's an interesting idea, definitely going to keep my eye on this and see what kind of response it gets.
And to add to that, what about clipping them at home with a die grinder?

[theman53]

That's an interesting idea, definitely going to keep my eye on this and see what kind of response it gets.
And to add to that, what about clipping them at home with a die grinder?

You could. Any mod to the turbo spinning parts will definately have a rebalance coming. I talked to a builder and he said older non ball bearing turbos spin 100,000-130,000 RPM the new ball bearing types spin 170,000 plus. So they need to be perfect:D

[R.O.R-2.0]

the size of the turbo has alot to do with how fast it spins.

i was told that the VNT on my rabbit spins 200-230k RPMs. and its not a BB turbo, its just tiny.

smaller turbos spin faster by nature..

[clbanman]

I wouldn't recommend it.  Balancing is so sensitive due to speeds that it is usually done not at the O.D. of the fins but on the nut holding the impeller to the shaft.   I've never seen real science or data numbers behind this.   Just for fun, here's a pic of an "involuntarily modified" turbo intake impeller.