350Z Dyno Test

Dyno test after installation of MREV2 and Spacer. Good news and bad news.

GOOD:
262.10 WHP, 252.47 WTQ, and huge gains in the midrange.

BAD:
Car now running extremely/dangerously lean.

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2006 Nissan 350Z Enthusiast

Mods to date:
JWT Popcharger
5/16" Isothermal Spacer
MREV2
Stillen HFCs
Stillen True Dual Exhaust

Category:

Autos & Vehicles

Tags:

• 350z
• 2006
• nissan
• motordyne
• mrev2
• spacer
• stillen
• high
• flow
• cats
• true
• dual
• exhaust
• jwt
• popcharger

[ambientflier]

Did you ever get it sorted out?

[oNAGAo]

Yeah, sure did. Turns out, I must have some sort of exhaust leak. I was still running lean, though - about 14+, so that had to be fixed.

I went down to Uprev in Austin while visiting my family and had the car dyno tuned. I'll probably post some videos of the whole thing sometime. Got the A/F ratio down to 12.9 and gained 16+whp at 6600rpm. So now the car is more reliable AND more powerful.

I'm loving it.

[ziveon]

what would be a normal A/F ratio number? and how do you obtain such information? thx

[oNAGAo]

Normal A/F ratio when idling is about 14.7'ish. At wide-open-throttle (WOT), most tuners prefer to have it around 13 or just below, though there's a range in there that's relatively safe. You go too low (rich) or too high (lean), and very bad things begin happening to your engine that could absolutely ruin your car.

There are various ways to get the A/F data. A common method is a "sniffer" device stuck in the exhaust pipe. Others include sensors farther upstream or simply plugging into the ecu.

[cbeck611]

@oNAGAo so does the mrev2 and spacer cause it to run lean or was it your exhaust leak?

[oNAGAo]

@cbeck611

It was a combination of both. The car wasn't actually running as lean as the dyno "sniffer" said it was - that was partially caused by the leak. However, the car was definitely running pretty lean (14.5'ish) after the MREV2 and Spacer. Not a bad thing if you get a tune to keep it under control - it's just what happens with these cars when you open up the intake airways as much as those mods do. If it didn't lean it out, it probably wouldn't be doing its job, really.

[ambientflier]

Your sound is what I'm going to try and replicate when I get my '07 soon. Although with a minor difference of 8000rpm instead of 7000 :P

Anyway, I hope you can get it figured out and still keep that torque number. That's like 300lb-ft at the crank!

[oNAGAo]

Yep. All the way to the 7000rpm cut-off. Thanks :)

[ambientflier]

Good luck! What are you revving to in this vid, redline at 7000? Sure sounds nice...

[oNAGAo]

The MREV is a plenum modification - a replacement for the stock lower collector. When combined with the spacer, it adds gobs of power in the midrange.

I'm sure it did lean my car out. However, I'm not sure the numbers are accurate. I feel like my car would be running pretty badly with some obvious symptoms if those readings were correct. Fortunately, there's a guy in town who's going to help me out. Wish me luck :)