turbo clipping
 

I read a post that said

Here is what Garrett says about clipping "Clipped Turbine Wheels When an angle is machined on the turbine wheel exducer (outlet side), the wheel is said to be `clipped'. Clipping causes a minor increase in the wheel's flow capability, however, it dramatically lowers the turbo efficiency. This reduction causes the turbo to come up on boost at a later engine speed (increased turbo lag). High performance applications should never use a clipped turbine wheel. All Garrett GT turbos use modern unclipped turbine wheels."

From reading that it seems like it wouldnt be a good idea to clip the turbo. A friend of mine has a GST Eclipse and has plans on clipping the turbo. I showed him that post and he says that friends of his have clipped the turbo and had no problem. What would be the purpose of clipping it? In what application would you clip the turbo? just seems kinda silly, and I dont want him to waste his money.

That was a post I made. The quote from Garrett pretty well sums it up IMO. A clipped turbine gains a
 

little exhaust flow at the expense of an increase in lag and a DECREASE in efficiency .... Better to find a turbo with more suitable flow.

it depends on what you are looking for....
 

If you want a small powerband way up high, a clipped turbo will get you more power, but at a greater lag time. The reason he says High Performance applications shouldn;t use clipped turbos is that they probably already have a big lag time, and increasing it only makes it worse. It probably hurts the turbine's efficiency too...which is bad

agree, find a better matched turbo to meet your goals.

He says one shouldn't use a clipped turbine for a high performance application because clipping
 

lowers a turbo's efficiency more than the small gain in flow warrants. His point is to size the turbo appropriately and there is no need to clip a wheel.

Some times there isn't a turbo for that. I think that is why they started using clipping.

Originally that is probably the case. Now however, you just have to pony up for a different series.

Re: Or try different a/r's.

That too.