So.. Just recently finished a FI kit on my 03 350z. Had it taken to a shop, installed by a professional. He's worked with Utec before and has quite a bit of experience with the programming. He tuned the Z before FI, with these supporting mods

1/2inch plenum spacer, ported intake, catback borla, Test pipes, stock headers.. Blegh I know.. and 660cc injectors, 255lph walbro. clutch ect.. But The issue is with the Utec.. He installed it and tuned and everything was great. except at around 4000-4500 rpm I would feel a slight cutout or short in power but only for like a fraction of a second, and under full load.. Didn't think nothing of it, and it didn't really show up on the dyno graph. Needless to say we went ahead and put on the Turbo and extras, and As he was tuning it it would cut out extremely hard. He tried tuning around it, but for some reason it wasn't happening.. We are running with a MAP sensor. Brand new. On the dyno graph, you can see where it just "dies" or cuts out and drops off horribly. He went to do some data logging on the highway and now it cuts out or sputters as if you had bad o2 sensor, from around 1200 rpm-4500 rpm.. once it hits boost its perfect.. not choppy at all.. Idk. It's pin pointed down to the utec.. Just didn't know if anyone else has experienced this before and what a solution is. Next step for me is go with UpRev Osiris.

 

I had a lot of problems with my UTEC, finicky stuff that was hard to pin down and fix. One thing I did find out is that it generates a high level of RF if the cover is removed. I made a lexan cover with more ventilation to keep it cool and when I was at the track the timing lights on the tree malfunctioned and I thought it was just a glitch in the system, however when it did it the second time I went back to the pits and replaced the original cover and all was fine, my bad.

UPREV is working much better for me but I just hope I can get the same consistency with the piggyback timing and fuel vs the UTEC standalone. Will find out in the next month or so.

 

Thanks for the response. Definitely let me know. I am ordering the $700 UpRev this evening from Z1. Like you said.. I hope it goes much smoother than this Utec :\

 

Uprev wins again