I'm determine to go FI in the near future (ST most likely) and was wondering if the currently available NA mods would be beneficial later on, for when I go FI? (Yes, I am being frugal).

Parts mainly in question are the MREV2 and plenum spacers...

I found these two threads (here) and (here), but they are rather dated.

My car is an '06, stock with the exception of an drop in K&N. Don't want to be spending money for parts that I can't use (or won't be beneficial) later.

 

Is you car manual. If you want to save money then just get a lower plenum from an automatic from 2003-2007 AUTOMATICS TRANSMISSION...port and polish the plenum and drop it in. It will cost you a 1/4 off the price and get you pretty damn close to same performance. The mrev2 is just a automatics plenum that has some porting/polishing done to it. I am not sure if there is any other "SPECIAL" tricks MD does to them but if you are strapped for cash then pick up a $75 plenum and do it your self. Rev-up plenum has shorter runers and rev-up motor benefits from having spacer/ longer runner. I don't think it will hurt you any to have an mrev2 if you have a turbo down the road since many automatics put turbo on their cars.

 

That's really good to know. I have a 6mt.

 

i have the mrev2 and 5/16" iso-thermal spacer. it was definitely money well spent. it makes a noticeable difference in the part of the powerband you spend the most time in. as for saving money... you wont have any trouble finding a used authentic motordyne one on here or my350z.com. they pop up all the time.

 

IMO I would use the Cosworth plenum for boost. If you plan to stay N/A then go with the MREV2 and motordyne stuff.

 

I had the Cosworth and didn't realize any significant gain vs a Crawford plenum. I now run a 1/2" spacer and stock plenum set up (non rev up). I think for FI, increased plenum volume holds some benefit (however you go about it). I would've kept the Cosworth but I had trouble with a small leak around the endcaps with methanol spray. Without spray it was fine. I was ready to redo the o ring gaskets with new ones, but just decided to sell and not worry about future leaks. Now that the Cosworth sells aluminum end caps, it might work better for meth spray...