Is anybody using the Screamin Demon coil pack and firewire setup? Just looking for insight before i buy one and make sure i am not getting a piece of junk that causes codes. Also looking for NGK recommendation for my 2007 3.8 v6 automatic. Replaced the plugs with oem about 7,000 miles ago but have had misfire issues. Jeep has 96,000 ish miles.
I doubt you would notice anything on the butt dyno. I would venture to say it will help smooth out your idle, "allegedly". I can't justify spending $200 to open spark plug gaps to .065. OEM coils are pretty stout, but that's just me. Courious to see if anyone has any insight too.
I have the screamin' demon coil and wire setup. It does not cause any issues with codes or the like.
As far as what you get for the money, ??? For me it fell into the category of doing every bit of 'tune-up' possible to make the motor as efficient as possible. I have E3 spark plugs, cold air intake (snorkel), K&N filter, and aftermarket exhaust. Basically letting the engine breathe easier and a strong spark for a more complete fuel burn.
I have no hard data to share on exactly the higher voltage coil and expensive spark plug gain. I will say the product is as advertised and if it is worth the $$... is up to you.