DMH Cutouts
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Agreed. In the instructions, DMH states you must drive the car with the cutouts closed, getting them nice and hot. Then allow the car to cool completely. This apparently helps seat the cutout valves so you don't have leakage later. I did this and don't seem to have any leak problems. I picked about about 10-rwhp over the ZO6 ti-exhaust I'm running.
I second everyone else's comments, those welds are absolutely stunning!
I had the pipes off my car when the cutouts were welded on. Once welded, I went back into the pipes with a grinder and file to remove as much metal as possible on the inside of the cutout flange (making the hole as big as possible).
Regarding whether these will pass inspection: It depends on your state. Mine just failed because I had these cutouts (of course they were closed). Apparently NC law does not allow cutouts of any kind on a car.
Kind of stupid if you ask me. Yes I can open the cutouts after the inspection, but I could also later tear my catalytic converters out too. They should inspect the car 'as-is' and not what it 'could-be'. Besides, I'm neither decreasing the level of safety of my car nor increasing emissions...so what's the problem!
I'm going to spraypaint the bottom of my cutouts black so they'll blend in with the underside of my car...hoping the next inspection station won't see them with their little mirror thing.
Of course the same inspection place also failed me because I had a breather for my PCV system on my valve cover. I tried to explain that it shouldn't matter if the PCV system sucks air in from the intake box or from my breather, but they didn't care and failed me because it wasn't OEM.
This is a really great mod and the low-profile is the only way to go on a low sports car.
I second everyone else's comments, those welds are absolutely stunning!
I had the pipes off my car when the cutouts were welded on. Once welded, I went back into the pipes with a grinder and file to remove as much metal as possible on the inside of the cutout flange (making the hole as big as possible).
Regarding whether these will pass inspection: It depends on your state. Mine just failed because I had these cutouts (of course they were closed). Apparently NC law does not allow cutouts of any kind on a car.
Kind of stupid if you ask me. Yes I can open the cutouts after the inspection, but I could also later tear my catalytic converters out too. They should inspect the car 'as-is' and not what it 'could-be'. Besides, I'm neither decreasing the level of safety of my car nor increasing emissions...so what's the problem!
I'm going to spraypaint the bottom of my cutouts black so they'll blend in with the underside of my car...hoping the next inspection station won't see them with their little mirror thing.
Of course the same inspection place also failed me because I had a breather for my PCV system on my valve cover. I tried to explain that it shouldn't matter if the PCV system sucks air in from the intake box or from my breather, but they didn't care and failed me because it wasn't OEM.
This is a really great mod and the low-profile is the only way to go on a low sports car.
I feel your pain and am sorry for the worlds IDIOTS! Hopefully you can find someplace that doesn't have IDIOTS!
BC
Last edited by Bill Curlee; Jul 12, 2009 at 01:51 AM.
Burning Brakes
Joined: Jun 2005
Posts: 782
Likes: 45
From: Toronto Ontario
Not to beat a dead post to death....
...but how exactly to these things seal. Is it like a throttle body, where the butterfly just wedges tight against the bore? Or does it seal against steps in the bore?
I only ask, because I know that even a *pinhole* leak in an exhaust system can usually be heard...
...but how exactly to these things seal. Is it like a throttle body, where the butterfly just wedges tight against the bore? Or does it seal against steps in the bore?
I only ask, because I know that even a *pinhole* leak in an exhaust system can usually be heard...
Racer
Joined: Oct 2007
Posts: 333
Likes: 0
From: Western Burbs of Detroit MI
+1
On another note, someone said they picked up 17 rwhp 17 rwtq ?? You must have a very restrictive catback or something bro. I have 1 7/8 arh 3 inch x pipe, 3 inch catback (LGM Big 3) and after the DMH cutouts were installed I only picked up .25 rwhp .11 rwtq !!! I love the sound and the sound alone made the purchase/install worth it but I was absolutely amazed at how well my catback flows !!! One last thing, when you open the cutouts the look on the peoples faces in the car next to you is priceless, or when you leave the cutouts open and start the car, even better. Everyone ducks and jumps. LOL. Sounds like a Nascar firing up. BTW in case you haven't noticed I love my DMH coutouts. Charlie at Vengeance did the install along with all the other stuff that got me to 541 rwph 505 rwtq in a stock esque driving 402. Your grandmother could drive it she's so well tuned.
Burning Brakes
Joined: Jun 2005
Posts: 782
Likes: 45
From: Toronto Ontario
I love the sound and the sound alone made the purchase/install worth it but I was absolutely amazed at how well my catback flows !!! One last thing, when you open the cutouts the look on the peoples faces in the car next to you is priceless, or when you leave the cutouts open and start the car, even better. Everyone ducks and jumps. LOL. Sounds like a Nascar firing up.
Scaring the **** out of good, honest citizens puts a
on my face.If you promise it won't sound like a clapped out Dodge Omni when they're shut, I'm gonna go for it.
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Burning Brakes
Joined: Jun 2005
Posts: 782
Likes: 45
From: Toronto Ontario
Just for ***** and giggles, wouldn't cut outs exiting out the side be kinda neat?
[/QUOTE]
Racer
Joined: Oct 2007
Posts: 333
Likes: 0
From: Western Burbs of Detroit MI
My car sounds like a simple bolt on car with a stock catback with the cutouts closed. Its only when the cutouts are open that she sounds as strong as she is.
Burning Brakes
Joined: Jun 2005
Posts: 782
Likes: 45
From: Toronto Ontario
Burning Brakes
Joined: Jun 2005
Posts: 782
Likes: 45
From: Toronto Ontario
One more question about these things:
How do the electric motors know when to stop moving? Do they have some sort of limit switch on them, or is it up to the driver to let go of the switch when they finish opening/closing. I believe our power windows and pop-up headlights have a current sensing circuit in them to cut power when movement stops...do these have that too?
No biggie if they don't though. Me still buying them.
How do the electric motors know when to stop moving? Do they have some sort of limit switch on them, or is it up to the driver to let go of the switch when they finish opening/closing. I believe our power windows and pop-up headlights have a current sensing circuit in them to cut power when movement stops...do these have that too?
No biggie if they don't though. Me still buying them.
Le Mans Master
Joined: Feb 2003
Posts: 6,682
Likes: 144
From: Memphis Tennessee
Operation is quite simple. The instructions tell you to not hold the button down more that 5 seconds. It only takes about 3 seconds to go from full open to close.....or vise versa. I think that the only risk of failure you acually have is to hold the button down and burn out the motors. Dave seems like a straight up guy and I feel he will stand behind his product regardless of what you do.
I love mine.
I love mine.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
I have a set and say there is no leakeage. Car is nearly stock sounding, yes it may be hard to believe, but she is quiet as hell with the cutouts closed.
+1
On another note, someone said they picked up 17 rwhp 17 rwtq ?? You must have a very restrictive catback or something bro. I have 1 7/8 arh 3 inch x pipe, 3 inch catback (LGM Big 3) and after the DMH cutouts were installed I only picked up .25 rwhp .11 rwtq !!! I love the sound and the sound alone made the purchase/install worth it but I was absolutely amazed at how well my catback flows !!! One last thing, when you open the cutouts the look on the peoples faces in the car next to you is priceless, or when you leave the cutouts open and start the car, even better. Everyone ducks and jumps. LOL. Sounds like a Nascar firing up. BTW in case you haven't noticed I love my DMH coutouts. Charlie at Vengeance did the install along with all the other stuff that got me to 541 rwph 505 rwtq in a stock esque driving 402. Your grandmother could drive it she's so well tuned.
+1
On another note, someone said they picked up 17 rwhp 17 rwtq ?? You must have a very restrictive catback or something bro. I have 1 7/8 arh 3 inch x pipe, 3 inch catback (LGM Big 3) and after the DMH cutouts were installed I only picked up .25 rwhp .11 rwtq !!! I love the sound and the sound alone made the purchase/install worth it but I was absolutely amazed at how well my catback flows !!! One last thing, when you open the cutouts the look on the peoples faces in the car next to you is priceless, or when you leave the cutouts open and start the car, even better. Everyone ducks and jumps. LOL. Sounds like a Nascar firing up. BTW in case you haven't noticed I love my DMH coutouts. Charlie at Vengeance did the install along with all the other stuff that got me to 541 rwph 505 rwtq in a stock esque driving 402. Your grandmother could drive it she's so well tuned.
It's a Kooks 1 7/8 headers into 3" high-flow cat/X-pipe and then into a set of TI's. I have the dyno's somewhere and it show's the difference. I don't know what else to say. One other guy got the same or similar results. Hey, it's a good excuse to open them.
Racer
Joined: Oct 2007
Posts: 333
Likes: 0
From: Western Burbs of Detroit MI
Again I didn't doubt you, just needed to know what catback you were running. THanks for posting up.
Safety Car
Joined: Oct 2000
Posts: 4,949
Likes: 10
From: Monticello MN
Racer
Joined: Oct 2007
Posts: 333
Likes: 0
From: Western Burbs of Detroit MI
I have the lgm big 3. LGM actually has some graphs showing Ti vs LGM big 3. The lgm big 3 picked up a ton. 14 rwhp or so and good amount of torque too. Check it out. The big 3 even gained over 7 rwhp and 7 rwtq over free flowing bullets. The lgm big 3 flows !!! Almost as good as cutouts !!!!
Racer
Joined: Jul 2007
Posts: 298
Likes: 4
From: Northbrook il
St. Jude Donor '12
Does anybody have the cutouts with just the stock exhaust system in the car? Is it mcuh of a difference between the stock exhaust and these wide open on the stock exhaust? It would be great to hear a sound clip or vid of this setup?