creaking and squeaking

What did you think lowering springs were going to do? All good and no drawbacks?

 

I obviously don't know the exact level of squeaking you're suffering from (it would take experiencing your car firsthand to know)... but this has been my uniform experience stiffening suspensions, including a 2nd-gen Integra GS sedan and a Is300. This is one of the reasons why chassis braces sell despite dubious benefits. People hope it would avoid the squeak and keep the car as solid as it was stock.

 

I was about to edit my prior reply to note that this also might be a PIP-specific issue, as Consumer Reports did rank the regular Prius as being really reliable and problem-free, while the PIP (and other plug-ins) wasn't nearly as well-regarded.

In terms of chassis braces... it's uncertain. In my IS300 when I was tuning it, it was fully-braced out with with two TRD subframe braces and a TRD RSTB. But my moonroof never stayed tight and creak-free.* In all fairness, none of those braces could have done much to control the torsional flexing of the passenger compartment (which was what was going on) short of a full cage, given that I was running gray-market Tein RS's (piggyback reservoir monotubes w/pillow-balls) and 22kg/mm fronts and custom-fabbed 18kg/mm rears.

In other words, I don't know for this car, and for this level of tune. Maybe ask around on the Modifications and Accessories forum?

* - trying to deal with that was how I found out how ridiculously heavy a moonroof is, any why I made the decision that I wasn't going to ever ask for a moonroof again unless it was on a super-overbuilt luxo-barge.

 

i have no pip squeaks, but there are a ton of threads here about 2010 squeaks.