3nick4

Starting to mod my '08 350z and I'm wondering if I should install test pipes on my stock y-pipe or would you recommend replacing both at the same time?

SQuaLZ

Depends on your budget. The HR Y-pipe is not a bad Y-pipe. Do you plan on changing the exhaust system or leaving it stock?

You are going to get rasp with this setup.

3nick4

SQuaLZ

If you are planning on leaving the stock exhaust system, I recommend going with a set of high flow cats or resonated test pipes.

AAM Resonated Test Pipes or Z1 High Flow Cats. Both are around $400 can't go wrong with either.

3nick4

MicVelo

Honestly, if you haven't already done so, save that $700 and do sway bars or good tires. More bang for the buck.

Exhaust mods, while they make one feel good about the car driving through a tunnel, suspension actually improves performance.

3nick4

MicVelo

The biggest names (or at least mentioned most):

Hotchkis
Eibach
Stillen
Whiteline

I like the Hotchkis as it is a tubular setup and weighs less than a solid bar but minor detail for sure. All but one of these (can't remember which isn't) is adjustable F&R so that you can tune your chassis to your preference and/or abilities. I suggest adjustables, well, because. You have options. Even installing them at full-soft on both ends yields returns.

Sway bars should be the number two item on any suspension build. AFTER tires. (THE most important factor in suspension that WORKS.)

Preachy?

Damm right. A good handling car is better than anything else you can do to your car, BAR NONE. Everything else is a fail if you can't put all of your 500 ponies power down and the car wallows like a pig in slop every time you turn the wheel.

To everyone else: Note I refrained from the driving school soapbox.