correct me if im wrong, but since the 05 xterra has the same engine as the 350Z(with bigger displacement) will the aftermarket for the Z work on the X?

Hmmm The 05 Xterra has a 4.0 liter 265hp engine, the 350z has a 3.5 liter 300hp engine, they are not the same.. but there will be plenty of perfomance parts out there soon for the X!!!

well my owners manual says it has the same engine platform but a bigger displacement. i dunno

Well they both use the VQ series engine, but are completely different engines...
the valve and intake system is the same style....

OH IC thanks for clearing that up.

Just to reinforce the above facts, I have both an 03 Z and an 05 Xterra. I thought the X had the same motor as well, just detuned. Its a radically different motor. The oil filter isnt in the same spot, and the Z's engine looks massive in comparison to the X's engine.

I cant imagine what is similar between the 2 engines since they look so radically different.

They are both from the VQ family of Nissan Motors, which was a variable Intake design, that is the only similiarity. they are definetely different motor.
They both use Lightweight Teflon coated Pistons...

While we're on the subject, is the 02 - 04 S/C motor the same guts as the standard 3.3 with an intake and a few extra pulleys added? Maybe different exhaust also?

From looking up exhaust for my 02 S/C, it doesnt ask if its supercharged or not. So Im thinking they have the same exhaust. Im wondering if I could use the serp belt from a non supercharged and eliminate the supercharger until I need it?

Does the standard 3.3 engine have dual cat converters?
My owners man says if you run low octace fuel the knock sensors will make the s/c bypass, and you will hear a grinding or something, but I bet the belt has to turn for some reason

My xterra has 4 cats. The rear 2 have no O2 sensor behind them, so it shouldnt be a problem to remove them and just run the front 2. Makes no sense to me why Nissan would do this. Looks like 4 cat converters would restrict the system for a S/C engine?

Mine only has the two cats on the downward bends

sorry, ill have to contradict some of the previous posts in this thread, last time i misread it, the engines are the same, just the 4.0 is just that, a VQ bored out to 4.0, same as the origional VQ engine introduced with 3.5L displacement in the 01 pathy, same engine as the 3.0VQ in the infinity I30, the maxima uses the VQ, the new xterras/frontiers use the VQ, the 350Z uses the VQ. the oil filter being ina different place has nothing to do with anything but the location of the oil filter, its a truck platform, not a sports car platform. hence different location, you can even buy filter relocation kits, think about it. plus if they were radicallly different motors, then one would not be a VQ. the engine is the same size, bigger displacement from the 3.0VQ-3.5VQ-4.0VQ is the bore, which you cant see from the outside, the engine would look bigger in a 350, its a smaller car-in effect it has a smaller engine bay, of course it would look bigger. the biggest difference between the diff. generations/applications of the VQ other than displacement, is that some are de-tuned and some are tuned higher. a VQ is a VQ simple as that, if it were majorly different, like my VG motor is then it would be a VG or whatever else.

but to answer the origional question, no, the mods for the two cars arent compatible, everything around the engines mount deffierently for one thing, they have different ecu's, they use different fuel maps, the chassis and frame are different too. i think the only thing you could use on both would be a CAI, being that nissan puts the same air box in all their 2000-2004 VQ generation cars.

i run a gibson exhaust system for my supercharged 3.3L ;)

Hmmm The 05 Xterra has a 4.0 liter 265hp engine, the 350z has a 3.5 liter 300hp engine, they are not the same.. but there will be plenty of perfomance parts out there soon for the X!!!

It is not the exact specs, but it is the same engine. Don't believe the HP ratings.

As someone who has used the same block in different motors, I can share some experience here. The two motors share some designs, and maybe even some specs and minor parts, but there are major differences in design assumptions and parameters for each motor.

In other words: No, you cannot just bolt on parts. Sorry.

This is like someone with a Chebby 350 in their truck, bolting on a Corvette intake and exhaust, and expecting the same performance. Without changing the camshaft profile, compression ratio, carb settings, heads, and other guts of the motor, you will not get anything out of it. In some cases, working at cross-purposes can actually reduce the performance of your vehicle.

Woody