What's the diff.?
 

I hear the terms REVUP, MREV+, MREV2, etc. What are all these terms describing? Does it have something to do with the 300hp engines? What gives these engines the 300hp over the regular 287hp?

Here's the quick answers:
REVUP=revised VQ35DE engine for the Z available in all 06 and up models with 6MT and 05 anniversary model. Has 300 hp due to variable valve on both intake and exhaust.
MREV and MREV2= plenums for the VQ.

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