I am in the process of installing a V1 Vortech Supercharger kit on my 2005 G35 RWD 6sp, revup engine. I went with a V1 becasue of the cold weather in Chicago; plus I like the sound it makes. The entire kit is installed, but the engine bogs down at 3000 RPM in every gear and the VDC light comes on. The install is being done at a Vortech dealer, so he's done some troubleshooting. He can bypass the pickyback ECU and run a jumper to the additional fuel pump and he can easily get the engine up to 5000 RPM. He hasn't taken the engine higher to protect it. Also, he dyno'd the car before the install and it put down 258 HP at the rear wheels, so the engine is in good shape still. He got a second picggyback ECU, new chip, and wire harness from Vortech and the problem still exists. He has been talking to Vortech all week and today they said they have another customer who is having the same problem, so I really don't think it's a bad sensor or issue with my engine. Lastly, my VIN has 04 for the manufacture year but it is definitely an 05; not sure if this could have hardware or software implications. Any ideas what the problem might be???

Welcome to NICO! I've deleted your duplicate thread. It makes things easier for everyone if you keep the subject limited to one forum.

The Vortech dealer should have access to dyno and other tools to read the system and find out what's really going on. Until that happens it's difficult to know why the system is keeping the car to 3k rpm.