nrgy

Finally got a chance to put my car on the dyno today using a mobile DynaPack. Found out about this meet on short notice, but was hoping to put the car on rollers but oh well. Someone was kind enough to post up a video of my car on the dyno, and the sound quality is pretty good/accurate.

http://www.facebook.com/video/video.php?v=280273415483

I'm running the MHP headers and tune, 300 cell high flow cats with secondary cats removed. Rest of exhaust is stock including the resonators. As you can tell, the car sounds BEASTLY with this setup.

A few things I should mention. I did not have the car in dyno mode, only ESP OFF. I didn't do my research in time Also, I do not know which gear they dynoed in. I was bit nervous for my car, and it escaped my mind to tell them to dyno in 5th. Lastly, it was pretty hot today for the NW. The temp reading in my car read 88 degrees at the time of the run.

Oh, one last note. Several other cars that ran (NSXs) said there numbers were off by nearly 50hp compared to when they ran on a dynojet. Also, since I had the headers installed I did not reset the tune by disconnecting the battery. Basically, I have not adapted the ECU to the headers yet to achieve maximum hp, and I have been driving like a granny lately.

Anyhow, I put down 425rwhp and 400rwt. I'll try to get a scan of the dyno sheet up. A guy next to me said the curve on the graph was the smoothest he's ever seen btw.

E55AMGFan

Good lord, the army, the feds, ants, ducks, the cops...everything will be awake and running for their lives when they hear something like that. Great numbers, what were the conditions like, temperature, humidity, etc.?

nrgy

Yeah the sound at WOT is insane. Not just WOT, but even just stabbing the throttle the car has a much bigger bark. Initially I wanted to take the edge off the sound and took it back to the shop to discuss options, but it's starting to grow on me. I've been getting a lot of thumbs up lately, although I'm sure there are many more shaking there head haha.

But the weather was fairly hot, 88 degrees indicated on the car gauge. Not sure on humidity. I do want to point out again though, that after others who dynoed compared their previous Dynojet numbers (and one even had a previous DynaPack dyno to compare), they came to the conclusion that something was not configured right on this dyno. Everyone was putting out lower numbers by as much as 40-50rwhp, and this would seem accurate considering everyone else with my setup has been achieving 460-470rwhp.

Anyhow, I'm not worried at all. In the end, the only number I care about is the one I can post at the drag strip, and that should be happening October 10th

Boost Gomez

What do you mean by dyno mode?

nrgy

There is a dyno mode you can access by pushing a few buttons. From what I understand, this turns off ALL the electronic aids such as ABS, ESP, etc, whereas ESP OFF doesn't fully turn off everything and could still interfere while doing a dyno run.

Even though I wasn't in dyno mode, I still think the operator managed to pull off a clean run.

patboyy

sounds great! MMmm...MHP tune....Nice

E55AMGFan

I know what you mean concerning the low reading as on a dynojet your car should easily be making those numbers. In terms of quieting down it, what would you have done? Add some resonators to tone it down? It's very loud but I prefer a little bit more crisp refined AMG note.

nrgy

Well, initially I was thinking to add a higher cell count cat. Right now I'm running 300cpi, and thought maybe I'd bump it up to 500cpi. More restrictive, but could tone things down some. I also thought about adding in the secondary cats again, but with high flow ones. But my shop didn't think there would be enough room since it is already a tight fit with the 3" tubes.

Lastly, they thought it might be possible to add resonators near the rear of the car, right before the mufflers. But I really don't want to start cutting the stock exhaust. Sooo, right now I'll leave it as is, and I might revist the idea after I hit the track in October.

But I kinda agree with you. It is fun to see people's reaction when you let the car rip, but I also enjoy that refined AMG note as you described. I will say, just crusing around the car does sound stock. There is a bit more engine whine in the cabin, but that part I kinda like.

Another cool thing with the setup I forgot to mention is the smell. It smells like a high octane race car, even though I'm just running premium.

E55AMGFan

Hmm too bad the cameras never pickup the real life sound. Only way for everyone and myself to really gain a judgment and opinion is to hear it and of course see the beast in person.