So my local Z club had a dyno day this past weekend, and I finally put my car on the dyno after I've had my plenum spacer and Nismo CAI installed on my '04 350.

After the pulls, you could smell some gas, little bit of smoke out the end, and the tech said it was running rich. I also maxed out at 225 hp out of my 3 pulls having a 6MT, which seemed odd because another 350 AT pulled ~230.

Are you able to lose some hp after aftermarket parts, and gain what you had, as well as gain from the parts after a tune? Or is there a different problem possibly at work?

 

yes you can lose some HP some with parts if you dont tune, surprised you are rich... usually you lean out. what kind of dyno was it because 225 seems really low

 

I know it's a Dynocom, but beyond that name, I'm not sure.

 

what was your A/F ratio? I know the revup and HR are designed to run really rich at the top to keep the heads from over heating. but like travlee posted, adding intake mods like that might lean you out, and you do see to be running really low numbers even for a stock Z. honestly I would do my best to get a dyno at another shop. my AFR (06) was 11.5 near the drop. I also dyno'd 260 bone stock to the rear @ sea leval on 91.(CA)

 

post a picture of the dyno sheet so we can take a look

 

does seem low...with an AEM intake and a stillen exhaust I did 246 in colorado...OP should put OEM parts back on when he re-dynos - JAT...