Everytime I read about NA mods I get excited and start to think everything sounds reasonable and probably works. Then I always get to a point where the picture gets cloudy. Like when guys buy exhaust systems that add weight to the car, change the backpressure and end up making the car slower. Or add weight with wheels and greatly up-sized tires that make turn-in slower, etc. I'm not writing to criticize, everybody gets to have fun by their own definition. But after buying and installing a grounding kit that made absolutely zero difference in the car, I'm looking at this plenum spacer and thinking, "That makes sense, but..." It makes sense to think if you change airflow front to back--intake, spacer, headers, exhaust--you'll send more air thru and go faster in a noticable way. But how to match up all these components? Does it matter if the same company has made all the pieces? And do we really improve on a product designed and made by engineers who are obviously better at this than we are? Perhaps there's no definitive answer to this, but I'd be interested to hear from skeptical readers like me. If I'm not willing to go FI and only want to make changes I can feel, should I bother to do anything?

 

well if your the skeptical. And need that make BANG for your buck, then Nitrous is your first step.

 

Study the Motordyne plenum spacer dynos. If you believe the test results, and are happy with the $$$/performance value, then buy and install the spacer. If you are doubtful about performance, or the $$$/performance value is too high for you, then don't do it. Pretty simple.

 

I got great response with the space. As you can see from my sig I gained 17whp & 10wtq N/A.

 

Thanks Robert K. that's helpful. I looked at the link and have to think a 17hp bump w/ added torque is noticeable! But of course you did kind of a "system swap" instead of just adding one piece. And it looks like you've kept a stock muffler setup but replaced the cats w/ a race pipe, (you're not running a straight pipe from headers out-that would make the car explosively loud for the street, right?) So if you've added a pop charger, spacer, race pipe but kept a stock can, how would you describe the exhaust note now? (I'll have to research and see what the UR crank pulley thing is all about.)

 

The increase is noticeable. At a track day I was pulling in Zs that were not running any "power performance" mods. Though they had suspention & brake mods that would help them keeps there speeds through the turns. I am still running the stock headers and cat back, cat-delete/race pipes only. As far as the exhaust sound there is a bit of a rasp at full throllte. At hwy speeds you don't really hear the exhaust. I like it that way though. Also other Z owners have told me it just adds to the stock note. Hope this helkps you out more.