What effect will a larger compressor wheel have on engine response and low end torque for a street/ track day car application. I have decide on a garrett g25 550 with 0.72 turbine housing... what I find confusing is according to Garrett boost advisors the g25 660 also meets my requirements... essentially they the same only the 660 has a bigger compressor wheel..

What would the negative be going the bigger 660hp capable turbo compared to the smaller 550hp

I'm targeting 350whp so I think the g25 550 is the correct option but our local agent advised me to take the 660 because he recon s there no negatives.

The larger compressor will be slighlty slower to respond, it will also be more likely to surge at low speed.