Can I use 2 ohm speakers in my 8th Gen. Since the stock HU is set-up for Honda's 4 ohm speakers, what will happen if I switch them to Infinity Kappas that are 2 ohm.

you'll overheat the factory amp and probably kill it. Cutting ohm load in half makes amp work twice as hard and hotter. Every 10C you increase an electronic component you half it's life.

if you use a different amp, you'll be fine. it will make those kappas sound great too!

you will definitely kill the stock amp.

I did contact Crutchfield and asked the same question. They recommended to keep with 4 ohm speakers but if Infinity speakers are a must, then go with lower wattage Reference and keep the wattage down.

I think the safe thing to do is either get a 2 ohm capable amp and Kappas or just shop for 4 ohm speakers. I think I will try the later and keep the stock amp as this is a leased car and I can easily remove speakers in 3 years.

I installed (about 3 weeks ago) INFINITY KAPPA 60.9CS in the front & INFINITY KAPPA 62.9I rear. I have the 09 LX-P 6 speaker system.

The Kappas sound better than the stock speakers, but stock HU and amp. doesn't push these speaker at all. I plan on adding an amp., either the JL Audio CL441DSP CleanSweep or Mtx RE-Q5 Bass & Signal Restoration, and/or a sub woofer.

FYI:
The following is from the Kappa brochure:

"All Kappa Series speakers are “true
four-ohm” – they include reduced
voice-coil impedance designed to
extract the most power possible from
all amplifiers engineered to drive
loads of four ohms or less. Many
factory-installed systems incorporate
two-ohm speakers and include
amplifiers designed to drive those
loads. Replacing those reducedimpedance
speakers with four-ohm
models is hardly an upgrade, since
the power output from the amplifier
will be reduced. True-four-ohm
addresses this as wel"

have you heard those infinities before you planned on buying them?

Thanks Attar, I think that settles it for me. Reading the Kappa brochure and some more research makes more sense. The Kappa "True four ohm" speaker is designed to swap out in vehicles while using the stock OEM headunit.

I think I will do something similar to your front / rear setup and I already have an Mtx RE-Q Bass & Signal Restoration, and a 10" JL Audio sub woofer and amplifier.