DMH electric exhaust cut-outs/dump valves

[Spidercat]

O.K>
Finally got around to uploading some videos of my exhaust. I was always jealous of Fonzie's exhaust, and his custom guy wasn't up for making a second, so I did a work around. RS6Dawg gave me this idea a couple years ago (he had this done by 034 I believe, but no sound clips). Sorry in advance about some of the shaky vids. Also, traffic around here is a bitch, so most of these were a little self-indulgence on my part after getting called into work in the middle of the night...

I couldn't add the url as an attachment or upload them directly, so went through the neccessary evil of youtube and posted the links below. Mainly wanted to see if it worked, so more to follow- some of the longer ones had problems uploading due to using a civil-war era browser.

BTW, for those that don't know, I have DMH low-profile electric exhaust cutouts (aka dump valves) where my cats used to be. Had them for about a year-- no problems with the motors, leaks, or connections (other than one short early-on that was cured w/ a zip tie to keep a loose wire off the hot exhaust). I couldn't be happier--super quiet (comparatively) stock exhaust when closed, and full-bore earth-shaking hardcore when open at full howl. All at the flick of a switch:



Left is cut-out rocker switch, right is laser jammer switch.


(It seems kinda muffled in the videos. Seems like I can hear all 40 valves and the turbos spool about a mile away! Well, to me anyway...)

Enjoy!

http://www.youtube.com/watch?v=PnY91N_AHwk

http://www.youtube.com/watch?v=d-8JtcWjh3s

http://www.youtube.com/watch?v=W3qop8lkeZw

http://www.youtube.com/watch?v=Lz9kAz7KfJU

Also, as was discussed previously, opened up exhaust from a dig- it's a dog off the line initially, but up top, it's a total beast!
I'll post more vids if I can, if anyone's interested.

[Spidercat]

Here are some others:

http://www.youtube.com/watch?v=tEZ0kd9sxgw

http://www.youtube.com/watch?v=0qvpmIy9fXo

http://www.youtube.com/watch?v=y-d1jS_rhq4

http://www.youtube.com/watch?v=uU2mDAXajiA

http://www.youtube.com/watch?v=a177rqIcvhM

[speedtrapped]

I heart this mod! Awesome...

[Spidercat]

Thanks!

Last 4, if you don't mind...

http://www.youtube.com/watch?v=E6xMh44ciVs (See what I have to deal with out here! Middle of the night speed trap! You can here the laser jammer kick in at the end to save the day- He's way on the other side of the bridge)

http://www.youtube.com/watch?v=pWIC7RZNX_s How fortuitous, but neither the 5 series or M3 wanted to play : (

http://www.youtube.com/watch?v=RCGdabAJdA0 (starts out closed, then opened, then closed at the end, just to hear the diff in exhaust)

http://www.youtube.com/watch?v=-J2hgt3_mTk (Tunnels....I love tunnels...)

friggin youtube vids are slowing my computer down big time.

[Spidercat]

Or you can just skip all those and watch this one instead---I edited them together and stabilized them so you don't get a seizure or find yourself saying "Thanks for the 9 sec video, ya douchebag!"

http://www.youtube.com/watch?v=IOfpS-eEkv8

[JSRS6]

See, that's what I want. You have any under-carriage pics?

[Spidercat]

I'll get some. Not a problem. I'll do it tomorrow (I guess your today!)

[JSRS6]

Haha. Mahalo!

[aussie rs6]

I'll get some. Not a problem. I'll do it tomorrow (I guess your today!)

Hi Spidercat,

I am even further ahead of you guys in the good ole USA- right now it is saturday evening 11pm. I am planning to do the same exhaust mod - catless dps with diverter as you have, so look forward to your underside photos and any installation tips and pitfalls.

regards,
johnk

[kismetcapitan]

the car is sluggish off the line with the DVs open? I'm sure that can be mapped out; when people lose power due to reducing backpressure, it's not that you *need* backpressure, it's that the ECU map is set up for exhaust backpressure.

[aussie rs6]

thanks kismetcapitan for the advice. much appreciated. APR have advised that they will change the ECU map for the reduced back pressure when I get the catless dps or dps with 100 cell cats done. Not as good as an individual map tune for the beast, but the best i can do here.

regards,
johnk

[kismetcapitan]

looking forward to pics - I assume the exhaust exit points won't melt anything?

[Beastly]

oh man, the WOT in the tunnel is awesome - un real. Love this mod. ++ for some pix

[aussie rs6]

looking forward to pics - I assume the exhaust exit points won't melt anything?

wouldnt want to warm the fuel before it gets to the injectors. that would get exciting!!!

some light relief for the married men on the forum:


At a wedding party recently someone yelled, "All the married men please stand
next to the one person who has made your life worth living."

The bartender was crushed to death.

[Spidercat]

the car is sluggish off the line with the DVs open? I'm sure that can be mapped out; when people lose power due to reducing backpressure, it's not that you *need* backpressure, it's that the ECU map is set up for exhaust backpressure.

You are right on the mark there. Very succinct way of putting it!
I chose to keep my Revo tune and deal with this minor inconvenience, esp since they are closed most of the time, and so that's where I want the "tune" to be (don't want to be fiddling about with electronic gizmoes and gadgets at a stop light just to find the right program).

I just keep them open for fun, closed for business (so easy to just open them up once seriously underway anyway). You could certainly maximize the tune for when wide open, but that wasn't the route I wanted to take.

Pix will follow tonight--turning out to be a busy day for me today.

I'll also post some little tips and whatnot, aussieRS6. I actually put a lot of thought into this before doing it, and happy to pass it along...

Thx for the compliments, btw, guys! Glad you like. I'll have to get a better mic or something, because my digi camera (wife's old one) just doesn't capture the sound. I was rather disappointed in how the vids came out (hence why I never posted them before). Videography just isn't my forte, and I'm comfortable with that.

[Fonzie Audi]

sounds good bro!

[Spidercat]

Thanks, man! Good to hear that from you!
I need to get my own trunk monkey for the in-car vids! Your trunk-cam was classic! No way to top that one. That was shear dedication.



Here are a couple pix from under the passenger side. They are a little fuzzy since I was just reaching under the car. Didn't get a chance to pull it up on the ramps today. I'll try tomorrow. Maybe a vid with them opening and closing. They open/close really quickly. Maybe a second or two? You can also control how opened they are incrementally, although why would you want your car to sound like it had an exhaust leak?

Also, they are designed so that if the motor goes bad, you can just unplug, unbolt, remove and replace. Two separate cover plates are included to close the holes. They were about $450 (DMH low-profile) for both shipped, but that included some custom gaskets. I'll have to dig up where I got them.

It was about $600 I think for all the labor and extra SS pipe (to replace the cats). That was the closest place after the turbos that they would fit. Anyway, we had agreed upon a price at the outset, but the guy spent way more time on it than he thought he'd actually need. Afterward he said if he was going to do another he'd charge almost double. Extra bungs for the secondary O2 sensors were included in the price also.

Later, I also bought the O2 sensor spacers (from 42 draft design) to add to the secondary O2 sensors to reduce the secondary O2 sensor CEL from 1/month to q 6 months. I just clear them out when they come up, but I just hate seeing that stupid light come on indicating that my bank account may soon be leaking...
I posted these on another thread, but here they are:
http://store.42draftdesigns.com/O2-S...cer_p_306.html

Initially, there were one or two small but audible leaks at the welds on the top side of the exhaust, which were quickly fixed, and the one short-out about a week later which was fixed. Since then, no probs.

I, too, was a little worried about the lines running lateral to the exhaust, so I eventually put hi-temp reflective covers on them as they pass by the exhaust cut outs, but I never had any problems.

One more thing: don't close them all the way with the engine off- they will seize closed, and they are a bitch to manually open without removing! The motor will back the butterfly valve off ever-so-slightly while the engine is running once you close them after you take your finger off the rocker switch. Otherwise, it's possible to close them too tightly. Ask me how I know.

Lastly, if your looking for these to be totally unnoticeable at idle when closed, then beware. I'd hate to mislead someone about this. There is a very slight chatter at idle (I'll capture this when I post the other video of the underside) when running in park with them closed. Once it's in gear with the brake on, however, it goes away. It probably has to do with the resonance at such low rpm, and not having enough pressure in the exhaust system at those low rpms to force the valve completely closed. If you're an idiot (like me apparently) then turn the ignition on (but don't start the engine) and close the valves completely. They won't chatter, but you will not have fun trying to get them open!
That said, it doesn't bother me in the least. Not in the least. I've been called a perfectionist (among other things), but never a prima donna, however.

I'll try to get it on the ramps tomorrow.

[speedtrapped]

Great write up, looks great