Dads C63

Now thats FUNNY!!!!!!
Isn't R&D work fun.
I think you could have probably bought some L/T headers by the time you paid for the PLM manifolds, GT Pro Single X-pipe, the custom exhaust and your time and efforts. Looks great though.
Good luck at the track tonight!! Keep us posted.

AMS Performance

It would be a shame not to put an X-pipe in since it will improve both sound and power gains. Might as well put one in ....

Sincity

I had a 12" Vibrant resonator put in my '07 GTI with a catless DP. It toned down the raspiness and still allowed a free flow.

clkwork

Very, very cool stuff. If I were buying my car and money were no object I'd probably do the same. I ran my last car (c5 vette) with no mufflers for a long while and it was a blast.

RStevens63

Hahahahahaahahahahaha!!!! I just about died reading that!!!!

RStevens63

Turbo and Nat Asp exhausts have significantly different requirements and necessities. Lots of turbo guys (cars to trucks) just run straight pipe all the way back from the turbo and never have any issues with noise. My neighbor has a decent modified diesel truck with aforementioned straight shot exhaust, sucker is quieter than a stock E63 exhaust at idle part throttle and floored! The shameful part is it's also hella faster than my E...

Sincity

I understand that a turbo already muffles the sound a little. On that GTI exhaust, I already had a muffler in the rear, but, I prefer my 4-banger to be a little mellow and not sound like a ricer. I never had a V8 before. Do you think a straight-thru resonator will quiet things down a little with Super's setup?

I guess he could always re-install the GT-Pro X.

RStevens63

I agree completely, nothing worse than a ricey 4 cylinder!No, you're also right that a resonator won't do much for an exhaust like this. High compression nat asp motors are just flat out loud when you decat them. Best solution will be cats but they will eat power, the Xpipe may change tone but won't do much of anything for volume. Either way sounds like Super has something in the works.

superlubricity

Nothing terribly exciting to report. Sadly, conditions were a bit worse today on the dyno (compared to March) and there were not any measurable gains with the catless setup vs. my previous stock primaries plus X-pipe setup. We're still scratching our heads at this one.

There are also a couple fitment/clearance issues with the pipes that we'll need to tweak before I run them again. Previous setup is going back on so I can compare in this warm weather. I have some fresh track times from tonight to compare to next week.

One positive note. The O2 simulators are working perfectly. No CEL and as expected AFR is dialed in @ 12.5:1 @ 6,000 RPM. The ECU adapted nicely.

So that's it. No fancy write-up until I can get some more meaningful data.

clktoc63

[QUOTE=superlubricity;4169679]Nothing terribly exciting to report. Sadly, conditions were a bit worse today on the dyno (compared to March) and there were not any measurable gains with the catless setup vs. my previous stock primaries plus X-pipe setup. We're still scratching our heads at this one. QUOTE]

7:22am and I feel like someone crapped in my cornflakes.
...I'll eat around it though until the new results. Of all of the cars I've owned, this C63 is by FAR the most sensitive to warmer weather. My butt-dyno says the car is a slug lately.

Good luck...look forward to the comparisons!

hhughes1

[QUOTE=clktoc63;4169846]A few trips to the drag strip last summer support what you are saying.

December 2009 mid 11's 121+ mph

July 2009 low 12's 117 mph

heat and humidity......nobody's friend

Ghostrider

Does the ECU not need the usual 200 miles to fully adapt?

RStevens63

Good, bad, or indifferent, thanks for sharing!

AMS Performance

You need the X-pipe, put it in there and the gains should show up. Right now you don't have any crossover of any kind.

superlubricity

Interesting. You don't feel the crossover connecting the stock resonators is sufficient?

AMS Performance

not at all, you need a true X-crossover for proper scavenging effects. The closer it is to the headers the better.

hope that helps,

AMMO1000hp

Super, I agree with AMS about the x-pipe. Granted I only eliminated the sec. cats but I did test out with and without an X. The first setup I tried was a decent X-pipe in their place. I then went with straight pipes and took the X out. I definitely noticed a slight drop in power so for the next setup, I went back to an X(nicer design) setup and got the power back. I realize this was not dyno verified but I did feel the difference. I wasn't able to spin the wheels up top like I did with the X-pipe setup. That was enough proof for me to come to this conclusion. Just my .02c


Anthony

superlubricity

It does help and thanks for the feedback.

I assumed the existing crossover tube in the resonators would serve the purpose. I can easily add my X-pipe into the system. I'll give it a shot.

RStevens63

The primary purpose of using a crossover pipe be it H or X is to increase torque. Straight pipes without a crossover of any kind will still make the HP up top. From what I've seen people are making good power and torque with the factory resonator aka mini crossover H, that is to say the gains from adding an X pipe don't seem to do much, and those that delete the factory resonator crossover aren't going any faster than those that have them.

RStevens63

No quantifiable before & after data?

Sincity

That makes sense because Super said he didn't notice any gains after he removed his old setup and install this new DP. He just equaled his power with the original setup (factory primaries and GT Pro X) using a DP only. Put the X back in, and you'll see the gains; even in this warmer weather since his last dyno.

AMMO1000hp

No, sorry. I wish I did. I was planning to do so but I did all these setup winthin a few weeks time. As I stated, numbers/data is the best and only way to 100% confirm this but it was a noticeable difference not just the "butt dyno" deal. It was most noticeable by doing a rolling start then punching it. Spun the tires up top with the X setup and did not without it. Again you can take with a grain of salt but it was a noticeable difference to me.

superlubricity

It appears I was severely underestimating the benefit of scavenging. We'll see in a couple weeks. Going back to the track with the stock primaries + X-pipe first.

RStevens63

Understood and thank you for taking the time to post your feedback.

AMMO1000hp

No problem. I was hesitant to post my experience due to the lack hard data/numbers. I am just anxious to see what kind of a difference it will make on a setup like Super's.