Hey guys, just got an 07 G35 coupe yesterday. I have about 1k budget for performance parts (I know pretty limited for now). My question is obviously I have done research and browsed through sticky after sticky, but I cannot come up with much information on the MREV2 and 5/16 plenum for the automatics. 99% of what I find on any forum for g35 performance is for a 6 mt. I am using my car as a daily and I don't plan to do a lot to it (I am holding out until I can afford a c6 grand sport). What I do want to do is up the daily performance with some cheaper bolt ons.

My question is does the 5/16th spacer and MREV2 offer much bang for your buck on the 07 AUTO coupe? I have seen some posts saying the MREV2 is basically a ported copy of the automatic g35. Is this true? Would just the spacer give me enough noticable difference for it to be worth it? I don't plan to do anything else like exhaust or more costly mods. What would you guys suggest?

 

The Mrev2 was designed mostly for the manual transmission equipped '05-'07 that had a slightly different motor called the "rev up". You only need the plenum spacer, also get a high flow cat or test pipes, those are your two biggest HP gains, preferrable coupled with a good catback exhaust but that will break your budget even buying a used system.

 

Thank you much cleric. That clears up alot. I have seen some things about the test pipes. With my limited automotive knowledge can I ask you if the test pipes will work (well enough) with the stock exhaust system? I do not really wanna shell out a grand for a catback system before installation. Can i throw on the test pipes with the stock exhaust and then add the spacer for two decent bolt ons that will up daily performance? If that is do able what test pipes do you recommend?

 

You need to absolutely understand what the emission laws/inspection system are in your state if you go the test pipes route, and maybe if you go the hi-flow cats route. Some folks need to switch out their exhaust setup every year when they go for inspection. Remember that test pipes are stinky. Do not underestimate the stink!

The other aspect is if you open up the diameter of the exhaust with an aftermarket setup, then you also want to open up the intake side of the equation. "Air in" wants to balance with "air out."

Get the system figured out and installed, then get your tune. You'll get a few more horses from mods and tune, but the really noticeable improvement will be in the smoothness of the power band... you'll get a good pull going at lower rpms and it will be solid through to redline.

 

It stinks pretty bad I'd never recommend it for a DD or one that you regularly drive friends in. HFC in that case.

 

Unless you have a turbo, don't do test pipes. Most are useless and sound like **** on a N/A car.

 

I definitely don't recommend cheap test pipes (or cheaply made components for ANY aspect of a vehicle), a good set will run you about the same cost as a good HFC so it really comes down to user preference and local emissions restrictions. I highly recommend you find someone locally that has different combinations of test pipe/hfc/stock exhaust vs various aftermarket cat backs and listen to them in person before making your decision. This will also let you experience for yourself the difference in smell between a HFC and test pipe. Some people think it smells horrible but I honestly can barely tell a difference, it was a lot worse back in the carbureted days with poor fuel ratio management.

Resonated test pipes on a quality system sound great, especially on higher revving motors like the VQ (sounds even more amazing on the rev-up VQ).

Cheap test pipes on a cheap exhaust system is possibly the worse sound to ever come from any motor... ever...

As with any performance engine mods they are best used in conjunction with OTHER mods, intake/plenum spacer/hfc or test pipes/cat back/tune all work harmoniously together. It's similar to a modern band, you need a drummer, bass guitar, rhythm guitar, lead guitar, and a singer. If you are missing one of those it sounds wierd and doesn't work nearly as well.

 

If it were me I'd go spacer, tune and Hotchkis or Motordyne sway bars. That'll put you close to $1000 if you are also paying for the installs and less if you can DIY. HFC's/test pipes on a stock exhaust almost always induce rasp and drone which I wouldn't be happy with. The spacer/tune combo will give you noticeably better power and drivability and the sway bars will make you fall in love with your car all over again. The change they make to the handling and feel of the car is dramatic.