I was looking at the technical specifications sheet for both the 06 and 07 m45 and noticed 07 m45 is rated at 325 horsepower and 336 torque while on the 06 model the spec sheet shows 335 horsepower and and 340 torque. On various websites it also shows the 06 has these numbers and more power than the 07 models,anyone know why this is? Is the 06 model actually faster or did infiniti just use a different dyno etc that caused lower numbers. If it is in fact more powerful I wish I got the 06 model since from my knowledge there is no difference between the two.

The SAE updated their guidelines on vehicle testing sometime in 2005.
The purpose was to standardize the procedures to produce more reliable and repeatable results, and also to make sure consumers were comparing apples to apples across different manufacturers.

You'll notice that some vehicles whose generations spanned the 2006-2007 model years ended up with lower numbers despite carrying a relatively unchanged drivetrain.

So, if the 2007+ models were to be tested with the outdated standards, it's possible that they could have published the same numbers as the 2006 models. Or more, who knows.


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Personally, I wouldn't sweat a measly 10hp and 4 lb-ft of torque at the crank.
How fast a car is depends on a lot of factors...and there are many variables in a14-year-old car which can render old magazine reviews pretty useless.

I've owned a lot of M45s, I still chose to keep my 08.

I see thanks and thanks for always replying to my youtube comments as well I go by akira maruyama on there but recently changed my youtube name to akura haha, Youve really helped me along my journey with my car ever since I was about 18 your videos helped me tremendously especially back then when I had no clue what I was doing.

On a side note do you know the most important variables that negatively impact the m45s hp and torque as well as handling? Im trying to keep mine for a long time ive replaced and fixed dozens of things but just need some new ideas!