i keep seeing turbos that have been ported and clipped with 50 trim and what not. i know what the porting is. but can someone explain trim and clipped to me please? id appreciate it.

 

A clip is where part of the turbine wheel is removed to let air pass over it faster. Better for high boost situations, but it will increase turbo lag.

 

Beat me to it..

But yep.. basically it increases lag but allows stable boost at higher RPM's where a turbo might otherwise begin to fall off..

clipping (like what was already mentioned) is generally done on the turbine wheel to create a little bit of "Clearance" for the exhaust gasses to pass, unfortunately that clearance means it needs more volume to start spinning it again, so it increases lag.

I've also seen compressor wheels clipped to produce boost at higher RPM on turbos (or cars with turbos) that don't have any turbo options and they want something that produces boost through a higher RPM.. As far as I know, this isn't a good thing to do and it isn't done much anymore.

Thanks to better technology and more turbo components and parts, I'm fairly certain you'll see most turbos are much better matched to their application and therefore you don't see clipping done as often.

 

also used more for drag race applications.