What are the pros and cons for s plenum spacer, and test pipes? I have a 2003 350Z Touring package, with a K&N Typhoon intake, and Injen SES Exhaust.

 

mo powa, mo noiz

 

give the intake/exhaust section a gander and read around there some

 

Welcome. Its a good question. Better than the ambiguous What do you think?

Plenum spacer and test pipes? I see no downside other than potential emissions inspection and testing.

 

Nothing but pros in regards to getting a plenum spacer made by Motordyne Engineering. You may run in to problems with some of the others in regards to the strut bar not fitting etc.

As for the test pipes, it will definitely make your exhaust louder and if they are not resonated they tend to add rasp to your exhaust note as well. The gains are nice since it allows your car to breathe better than the OEM cats. If you want more flow without the rasp you can also look in to resonated test pipes or even High flow cats. The tolerance each individual owner has for the exhaust noise level will vary so it will be dependant on what your tastes are.

 

pros on both...go with motordyne.

on the test pipes you may get some rasp and emissions penalties if applicable.

 

no cons whatsoever with 5/16" spacer.

for info on test pipes and check engine lights check the top 100 questions thread.

check the link in my signature.

 

so has anyone in NC passed emissions with test pipes?

 

I agree with everyone here, no cons on spacers. The only cons for test pipes are the smell, and the rasp. Some of us actually like the smell of unburned gasoline burning our eyes , we get tears sometimes.

 

i read the FAQ and it said that "If you are a rev-up owner, you will most likely benefit the most from getting both a 5/16" spacer and the MREV2. If you are a 287hp owner, great gains have been shown from installing only the MREV2 with no spacer." So does this mean that if i'm a non rev-up owner, i should hold on the spacer and just get a MREV2?

 

I think you would benefit more with the spacer and the MREV2 only because if used in conjunction with other performance parts ie;headers, test pipes, engine management, the gains will be higher.

 

Probably a noob question.. but just to be clear about a rev-up vs Non rev-up... an 03 would be Non rev-up because it already has an MREV built in? Sounds a little backwards in my mind, but that's what I gathered from the Top 100 FAQs in Wired's signature...

 

If you have 287hp motor, it's a non-revup. If you have the 300hp motor (2005 Anniversary & 2006 M/T), it's a revup. Please someone correct me if I'm wrong.

 

Easiest way to tell what motor you have:

look at the redline on the tachometer

6600RPM = non-revup 287hp (Factory lower collector is equivalent to the MREV)
7000RPM = revup 300hp (Unique lower collector tuned for higher RPM, but loses mid range torque)

 

The cons of a plenum spacer are the fact that you basically add another sealing surface to potentially leak, and they do not level out the front of the plenum enough to give equal air flow and air distribution.
The cons of test pipes are they are highly illegal and smell and are noisy..

 

another con for test pipe is that you trade in some low end power for top end power

 

What is the penalty for being caught with test pipes? Is it likely that a cop will notice if puller over?

 

Depends on different states.

Since our cars are so low to the ground, it's pretty unlikely that they'd notice. (Unless they have some kind of mirror on a stick?)

Plus, the car runs at stoichiometric air/fuel ratio when at idle (and warmed up) so it shouldn't smell too bad like unburned fuel if the car is warm.

Most likely it's a fix-it ticket, where they tell you you need to get your cats put back on then go to a state exhaust referee and have them certify your car is okay and has cats. Then you pay a fine or something.

I'm not too sure though.