Hello

Im currently looking at purchasing a 2004 or 2005 g35
I know they both have different horsepower ratings
but I heard nothing in the engines were changed just
the way they measured the HP? If not did they do
a reprogramming of the ECU? If I get a 2004 can I get the
dealer to reprogram it for the extra HP in the 2005+?

Thank You

 

I don't think Nissan changed the way they measure the power they report. There were some SAE standards changes in '05 and '08 I believe, but not all manufacturers certify to these new standards. The only power differences I know of between the '04 and '05 is for the 6MT models which was the introduction of the "Rev-Up" motor. There are differences between these engines so it is not just an ECU difference. I don't think there any differences in the '04 to '05 5AT models. At least not in terms of the engine, there were some changes not related to the engine however. Do a quick search and you will find tons of threads on the differences.

 

You may think that because of the higher rev-limit, but in order to get that rev-limit they changed a bunch of things in the engine.