so never really knew what turbo wheel clipping was for a while..no real intrest untill my turbo came off. well now its that time checked shaft play and everything is good. already ported wastegate but def got to get it ported again. still had nasty boost creep. anyway researched it and says it gives better top end power..rx7 all upper rpm anyway. so it is 60 bucks for the clipping (not bad for little extra power). anyone done this and can you really feel the difference.

only clipped 10 degrees also.
looking for some insight
thanks

 

clipping a wheel reduces efficiency. it's sort of a necessary evil when you start messing with our stock turbos, or that's my understanding of it. It's my understanding that it does not increase power.

But somebody else who knows what they're talking about should chime in.

 

it reduces the overall efficiency, while shifting the (new) peak efficiency to a higher flow rate... basically reduces the backpressure caused by the turbo at high RPMS but sacrificing the lower RPM efficiency (which affects spool time, low RPM boost levels etc). Its a quick-fix on an existing turbo to shift the range it operates at when you cant (money-wise or other) get a turbo designed to operate in the range you want.

 

that's why the BNR stage 4, while capable of 400whp on stock ports, is known to be laggy. it has a clipped turbine wheel and the stock restrictive hotside

 

Clipping:
Clipping is the technique of cutting away some of the material on the fins of the impeller wheel of the turbocharger. In other words, to 'clip' a turbo is to make the fins in the exhaust path smaller. The cut is usually done at an angle of between 10 and 20 degrees - the bigger the angle, the more material is removed from the fins.

This may seem like a dumb thing to do, since smaller fins mean that the exhaust gases will impart less force to the turbine wheel and consequently increase turbo lag. This is true, but the benefit of clipping is found in the high RPM range of the motor. At higher RPMs, the turbo may have already surpassed the required user-set boost levels and is not contributing to engine power.

Since the impeller wheel in the exhaust stream partially blocks the exhaust gas flow (by design), it can act as a significant restriction at high RPMs, when the exhaust flow rate is highest. Clipping the turbo reduces this restriction and allows more air to flow past the turbo wheel at high RPMs, thereby improving airflow through the engine and increasing top-end response. (93 R1 @ nopistons)

thats the info i got from this. so overall its basically what you want in terms of response. more lag if you clip untill upper rpm. just hits harder up top. so in my opinion ill save my money for a upgraded turbo in future

 

Also - My loud, crude, but effective way to reduce backpressure.
It's can be nice & quiet when "She" is in the car, or for long trips.
Then, when you want to play, just open the door.

 

properly sized turbo with appropriate manifold ftw

 

just trying to domething small to get what i want...and saftly. . new turbo and mani not the way i was going this particular moment. it would be great if i had the money for those mods now. thats the only reason i posted this thread. opinions/ basically is it worth it or not.

 

Just make sure not to use it near a cop... since those are illegal.

 

Well said, its a band-aid for a super restrictive turbine housing. Hybrids are waste of time. You don't need a bigger compressor to make power anyhow..

 

The turbo shop near my house charged $25. They basically take a lathe and cut off a little bit of the exhaust fins. I have a hybrid to4 turbo that I had clipped and non clipped exhaust fins. I had clipped exhaust fins before, but because of burning oil issues, it was rebuilt again with non clipped exhaust fins. The clipped exhaust fins did give it more top end power, but a lil more lag.

it spools up faster with non clipped exhaust wheel, but the top end doesnt peak out as well