Z-Tube & Coupe Mid-Pipe Dyno'ed
 

I know that no one asks for it anymore but are still probably interested so I went ahead and had this done before putting on my stock intake tube and sedan mid-pipe. With the Z-Tube and Mid-Pipe (sorry I wasn't going to pay for run after run) my sedan put out a best run of 247 whp 221 wtq. After switching it out back to stock, my car had a best run of 242 whp and 222 wtq. I had a total of 6 runs done, and all 3 of the runs with the mods did a little better than the original parts. Dyno conditions were: 67 degrees, 29.92 in., 51% humidity. So if anyone is wondering whether or not the mods do anything power-wise, I'm fairly convinced that the answer is yes but nothing earth shattering. Why did I want to switch out the parts? I wanted to quiet the car down. Everything said about my stock sedan mid-pipe is true. The exhaust is just much smoother and there's no in-cabin resonance at low rpms anymore. I can hear the engine growl now. With the coupe mid-pipe I was getting a little droning and the exhaust note was inconsistent going from smooth to growling to silent and alternating randomly from there. I also noticed an increase in low-end torque but I have nothing to confirm this. I didn't ask for the dyno graphs because I'm just freaking retarded and it slipped my mind. So for everyone who has ever wondered, I hope this answers your question.

awesome. lots of people wil find this useful i am sure being that these are 2 very popular mods for a sedan.

what year is your car by the way?

If you can get the graphs from the dyno shop, that would be great.

There could have been gains/losses somewhere else in the powerband other than peak.

I have a 2005 automatic sedan.

Thanks for doing that, much appreciated!

you'd probably see another few hp and tq with an osiris tune, not to mention all the other awesome benefits of osiris. they recently lowered their pricing, it's definitely affordable now!

I'm already tuned by UpRev. (My baseline numbers from when I first dynoed my car stock on this dyno was 210 whp 203.8 wtq. However, the shop lost its data along with their calibration data so I don't know how relevant this would be, since this time I'm putting up nearly identical numbers to my car when all it had was headers and the MREV + spacer. That result was 239.3 whp 216.9 wtq.) I have since put on cams and the HR Y-pipe and had the car tuned. I have the graphs now with me, but no scan. I was wrong with my info and the previous hp/tq numbers were due to spikes. The stock intake/sedan midpipe matched the z-tube/coupe midpipe horsepower-wise to 4500 rpm then took over from 4500 rpm to redline with about 5 hp being the average difference throughout. In regards to torque, the z-tube/coupe midpipe had 5 more from 3700 rpm to 4600 rpm but the stock intake/sedan midpipe takes over by that point and outperforms by about 9 to 10 wtq to 6300 rpm. The max whp/wtq with the mods was 238.3 whp 215 wtq, and my stock parts put out 238.9 whp and 211.5 wtq. Needless to say, I'm staying stock.

hmmm, i got those mods, plus a few others. No tune though :(