There is people starting to mess with the 5 cylinders. They also have a bad rep for absolutely no reason. There is a guy in Michigan that will upgrade the 5 cylinder heads for like $1,300. He will port and polish it and put in bigger valves with heavier springs and re surface the head. https://www.skunkworksports.com/ Also Calvin and his dad are making big waves in the drag and drive community with there 4200 builds. All there 4200's have run 9's in the quarter. Even 1320 video has covered them a little bit. So give it some time but there will be a lot of performance parts coming for the Atlas engine family.The Ameri-Barra is a bad MFer. If a I6 can make 800+ the I5 should be 650+. If you can come close to what this guy is doing, you'll be a star. But do it with the 3.7.
Thanks for your replyWhat year is your H3? The P12 PCM in the 2006 is completely differnt from the PCM in the 2007 and newer. I know in the 2008 to 2009 Trailerblazer the PCM went to speed density tuning. I doubt you will find anyone who knows. But your best bet is to send a guy named Calvin a message his website is https://www.paccracing.com/ and his youtube is Nivlac57. There is also another guy in NJ that runs LOJ conversions he might could point you in the right direction. They make LS swap kits for 240 and 270 Z cars and make the CAN Bus from the GM ECU talk to the factory Nissan dash. That way everything on the dash works like stock.