Is the dyno chart showing crank or wheel HP?

 

Thanks MichaelL for the dyno results. How does the raw 325 hp from factory compare to the dyno 280 rwhp, or is the measurement "just another 5 to 7 hp"?

 

Wheel HP and TQ numbers- The Mustang Dyno bolts to the rear axles directly.

 

Michael- Thanks for your input on the data. I know that every professional shop tries hard to obtain "real" results vs showing high or low. How is it possible to know if your output results are high, low or dead on? Seems like there are so many variables to consider!

Ran my 996 on the same dyno with the AH pipes, seemed to realize about the same HP / TQ gains vs. stock. What do you make of that chart?

 

What makes these mufflers different from the other ones out there? It's pretty much proven time and time again that mufflers don't make power. How do they do it?

 

I really don't know and I would otherwise agree- it's one of the main reasons I've been hooked on the AH product.- That is a question to ask Brian at AH, the designer. He started to explain some of it to me once but it just went way over my head.
If you take a look at the website pics / vids it is plain to see that the overall design is engineered completely different than typical mufflers.

 

I would say that these resonators are just a little less restrictive then a regular exhaust and reduce the back pressure at the cats more then standard exhausts. They may work like removing 50 cells of the cat (in terms of back pressure) due to the low back pressure design.

 

I didn't pay much attention to the curve initially, but that makes more sense now. When looking at the charts posted, power is lost on the bottom end and shifted to upper rpms, which is typical for less restrictive exhaust parts. It's not a lot by any stretch and honestly if you're racing you're going to be running from 4K and up regardless.

 

Actually, car is stronger off the line than with the stock cans so there is some lower end grunt improvement taking place- On the TQ graph, power starts out higher and never dips as low as the stock line dips before the midrange upcurve. What is odd though is the slight crossover below stock line around 2800 and 3300. If you look at my 996 chart the power is either higher or follows stock line.

The only thing different with my 997 vs 996 is the addition if the RSS plenum. I'm going to be dynoing again this Thursday without the RSS installed. I will do three runs with stock mufflers and three runs with AH pipes. I'm curious how or if it will change the results. If you have any suggestions on how you would like to see it dynoed let me know, I am trying to document my results as accurately as possible.

Thus far, I can say with complete confidence that when I slap a set of these on, I notice the difference immediately with accelleration and response. Maybe it wouldn't be so much of a gain if my pcar was already highly modified, but considering my pcar is almost stock with just a KN intake, RSS and the AH pipes it is noticeable. At least this has been the case on both of my cars now.

 

You must have a very sensitive butt to dyno to notice an 8 hp difference on a 325hp car. I know I couldn't feel it.

It looks like these cans perform worse than stock when under 4K. That's not a bad thing though, that's just exhaust tuning. Whenever your in "performance mode" you won't be under 4K anyway....

 

Perhaps it's the added 10lbs of TQ and more free-flow that causes the noticeable diff?
On my 996 I had an added 14lbs of TQ, which did make a nice diff with the tiptronic.

Typically you get used to feeling where the car pulls strongly and where it is slightly lacking. It is a noticeable improvement though, at least on my cars. I have not really heard any comments along these lines from other AH pipe owners so until there is a general consensus I suppose it remains "unverified" and "subjective". Dyno results don't seem to hold a lot of credibility these days since there appear to be many ways the results can turn out different based on weather, hot / cold engine or person running the tests.

 

Thinking- to me the chart looks like they are better than stock off the line- am I misreading it?
Stock TQ comes on at 236 then dips to 219
AH TQ comes on at 264 and dips to 232
So even though the AH's TQ drops sharply initially and crosses over stock, it is still overall higher than stock- which is good no?

You probably know more about reading these charts than I, which is why I'm asking-

 

Thats good point, I was actually about to ask or say the same thing. Although after about 2,600 rpms the torque curve meets on stock and AH and from there on the AH is lower for a couple rpms.

One way or the other, I think I'll be buying the AH once I buy my C2S. I want to see more videos! A C2S would be even better too! (should there be any noticeable difference in sound vs C2?)

 

i just took off my headers, and the car sounds very tame.
no more drone, just throatier and a bit louder...
i think i am gonna put them back on since it felt like the car had more presence.

 

yea I noticed those dyno numbers are high, not doubting them or anything. I have a non-S C2 and with Borla headers and mufflers, I was dynoing just a little over 280 to the wheels, more in line with Michael's numbers. I guess the K&N and RSS plenum really deliver?