DMH E-Cutouts installed - Pics
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DMH E-Cutouts installed - Pics
Well guys, The Vette will be quiet no longer. I finally got myself the *much needed* E-cutouts, to open my exhaust to a much better sounding and breathing setup.
Wicked99 was kind enough to provide me with access to a shop, and help me do some needed work on my car this past Saturday
I had bought some tires for the car about 2 weeks ago, and I wanted to wait until I got the cutouts and do everything at once. So we got the tires mounted and balanced first. Then we did the exhaust work. I also was able to change my oil while the car was on the lift. This is much easier than doing it in the driveway under jackstands
We took the whole exhaust system from the manifolds to the catback down. The only place to put the cutouts under there and have them concealed is in the area right up under the trans. In relation to the rear wheels, they are right in front of them.
While I know this is not the correct way to get rid of the cats, We basicly gutted them. The proper way to get rid of those would be to weld a tube in their place, but we didn't have it at the time the car was on the lift. I will probably go back and do this before I have the car tuned. We cut windows in the cats, and busted up all the guts in those and cleaned them out to leave a hollow canister. It is hard to believe how a car breathes through those things
. We welded them back up, and then welded the cutouts in.
The control wires go up through the torque tube tunnel and through the shifter boot into the interior of the car. The wires are tied to the hot wire that supplied the cigarette lighter in the ashtray compartment. I don't use that cause I don't smoke, so no issue there. The existing hole for the cigarette lighter was a little big for the switch housing, which is .750". I think the hole is probably about .812" or so. I still have to make a mounting plate for that.
After getting them installed, I did get the sound I want mostly, but the one thing that kind of dissapointed me was the magnaflows. With the cats gutted, there is absolutely no reason that the magnaflows shouldn't sound good. There was probably a little bit of difference in the sound, but not enough to make any big difference. I thought that maybe the cats were causing the muffling of the sound, but this was not the case. Those Magnaflows are just plain quiet
. Kind of in the neighborhood of Deltaflow Flowmasters. The increase in performance is there, but the sound is not. I DO NOT RECOMEND that catback to anyone wanting a system to change the sound of their car.
However, with the cutouts open, I have a LOUD car
. It is on the inside anyway. It is loud enough where you pretty much have to keep them at least half closed to drive the car. With them open, the resonance and the drone is simply deafening There is a sweet spot that I have been trying to pinpoint. Less than half open, it kind of sounds more like an exhaust leak than it sounds good. 1/2 open to about 3/4 open is the sweet spot. Outside the car is definitely louder than it was, but not too loud.
I know that headers and an x-pipe would make the car breath better and sound even better, but for now I'm gonna have to wait on those. The price of those sysytems for a Vette is unreasonable to say the least, so I may get them one day but not right now.
I thought I was doing good with no SES light coming on after gutting the cats, but it finally did. It took it about 75 miles of driving to come on, but it did show up. I will be able to get the tuner to program the rear 02 sensors out and thus get rid of the SES light. A tune is something my car has never had and really needs, and with work this extensive I am going to have to have it. Here are some pics. please excuse my dirty car - was gonna wash it yesterday after all the work, but we had a blizzard come through
Again thanks to Wicked99 for the use of the shop and the help.
.
.
.
.
.
.
.
Wicked99 was kind enough to provide me with access to a shop, and help me do some needed work on my car this past Saturday
I had bought some tires for the car about 2 weeks ago, and I wanted to wait until I got the cutouts and do everything at once. So we got the tires mounted and balanced first. Then we did the exhaust work. I also was able to change my oil while the car was on the lift. This is much easier than doing it in the driveway under jackstands
We took the whole exhaust system from the manifolds to the catback down. The only place to put the cutouts under there and have them concealed is in the area right up under the trans. In relation to the rear wheels, they are right in front of them.
While I know this is not the correct way to get rid of the cats, We basicly gutted them. The proper way to get rid of those would be to weld a tube in their place, but we didn't have it at the time the car was on the lift. I will probably go back and do this before I have the car tuned. We cut windows in the cats, and busted up all the guts in those and cleaned them out to leave a hollow canister. It is hard to believe how a car breathes through those things
. We welded them back up, and then welded the cutouts in. The control wires go up through the torque tube tunnel and through the shifter boot into the interior of the car. The wires are tied to the hot wire that supplied the cigarette lighter in the ashtray compartment. I don't use that cause I don't smoke, so no issue there. The existing hole for the cigarette lighter was a little big for the switch housing, which is .750". I think the hole is probably about .812" or so. I still have to make a mounting plate for that.
After getting them installed, I did get the sound I want mostly, but the one thing that kind of dissapointed me was the magnaflows. With the cats gutted, there is absolutely no reason that the magnaflows shouldn't sound good. There was probably a little bit of difference in the sound, but not enough to make any big difference. I thought that maybe the cats were causing the muffling of the sound, but this was not the case. Those Magnaflows are just plain quiet
. Kind of in the neighborhood of Deltaflow Flowmasters. The increase in performance is there, but the sound is not. I DO NOT RECOMEND that catback to anyone wanting a system to change the sound of their car. However, with the cutouts open, I have a LOUD car
. It is on the inside anyway. It is loud enough where you pretty much have to keep them at least half closed to drive the car. With them open, the resonance and the drone is simply deafening There is a sweet spot that I have been trying to pinpoint. Less than half open, it kind of sounds more like an exhaust leak than it sounds good. 1/2 open to about 3/4 open is the sweet spot. Outside the car is definitely louder than it was, but not too loud.I know that headers and an x-pipe would make the car breath better and sound even better, but for now I'm gonna have to wait on those. The price of those sysytems for a Vette is unreasonable to say the least, so I may get them one day but not right now.
I thought I was doing good with no SES light coming on after gutting the cats, but it finally did. It took it about 75 miles of driving to come on, but it did show up. I will be able to get the tuner to program the rear 02 sensors out and thus get rid of the SES light. A tune is something my car has never had and really needs, and with work this extensive I am going to have to have it. Here are some pics. please excuse my dirty car - was gonna wash it yesterday after all the work, but we had a blizzard come through
Again thanks to Wicked99 for the use of the shop and the help.
.
.
.
.
.
.
.
Last edited by J S Machine; Mar 2, 2009 at 08:48 AM.
BTW: My guy was able to install them on the car. He welded the top seam from the inside. 
