Okay so I'm driving home from my Gf's house in the crappy geo metro.at 3 am ....thinking I wish my firebird was finished. I'm thinking about the loud exhaust system soon to be installed. Winding through all these subdivisions and neighborhoods and being the only car on the road. I realize how disturbing the bird is gonna be to the sleeping general public. Not to mention how i will probably get pulled over 3 times on the trip home in it.

So has anyone ever fabricated a cutout on your exhaust to switch the flow over to a quiet muffler like a dynomax or something.??? Then when i want the car to be loud it can be .,,,but on stealth missons I just switch the cutout and whallaah...im undetectable.

just a thought

 

search for "cutout" in the exhaust forum, should bring up quite a few hits.

 

wait...my understanding of what you are asking is to have two different exhaust systems on the car at the same time with a cutout to switch from one to the other correct? i never heard of such a thing and dont know quite what to think. There definitely isnt enough room for two systems though. you will have to get very creative with it.

 

http://www.jegs.com/cgi-bin/ncommerc...62&prmenbr=361

This is as stealthy as you might get. I think easy to install, cheap, cool. Really good for you i think.

 

Yes something like that. What about just past the cat, a y-pipe with a butterfly or gate type valve that allows you to switch the direction of flow. And have a very small quiet muffler hidden under the car.

or a small h- pipe past the cat that goes to the quiet muffler and a removable Cap on the outlet of that muffler ?

You could possibly have the cap or valve controlled electrically with a switch in the car to turn on or off,,,,or partially open, or more or less open. allowing you to have many sound alternatives.

 

little P I've been contemplating the same thing, but I decided against it because the expense, and extra weight would not add up to what i would expect from it. I'd lose gas mileage because the car's heavier, and lose cash because alot of the stuff would have to be custom made.

| |
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| |_____
|________ performance exhaust
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quiet exhaust

in "performance exhaust" mode


| |
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| |_____
| |______ performance exhaust
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quiet exhaust

in "queit exhaust" mode

you can sort of see how the little door switches from performance, to queit or vice-versa.

very similar to a cut-out, but both all outlets and inlets would be 3"

 

here, i did the search for you. plenty of information on here. i'm tellin' you, do a thorough search and you will find a lot of info...

https://www.thirdgen.org/techbb2/sho...ghlight=cutout

https://www.thirdgen.org/techbb2/sea...der=descending

 

actually neither of those has what he's talking about. he wants an electronic cut-out, but instead of an open exhaust when you hit the cutout, it goes to a muffler that's louder than his quiet exhaust. I bet you could just have a muffler welded onto your cut-out you know...

 

I'm not understanding why a normal electronic cut out won't work.

 

...and where in NC are you?

 

Werd!

 

I'm in Raleighwood....

not worried about a little extra weight or gas milage... I am more concerned with toning down the noise when i need to.

I just talked to a guy at work and he said. "yeah we used to do that. we had a cutout to straight pipe. the flapper was attached to a cable inside the car,,and when we got to the track we just pulled that cable..and wwwAAAAAAAAAAAAAAAAH " !!! (he was getting all happy about it)

So I drew this little sketch. Just not sure how these cutouts and flappers work. WHo sells electronic cutouts, or where can i see one. Did a search cant find one.

heres the idea

 

got a cut out on mine...here are some pics...got it capped here. Just got done with emissions that day. Had an electronic cut out, but it only worked for a day... Quick Time Performance...

 

ok, now i know what your talking about. i don;t think there is enough room for this exhaust system you are talking about. however, what i did a couple of years ago was replaced the cat with a race muffler made by moroso (spiral flow) and then put the cutout after that. so that the exhaust was going through the moroso muffler and the dynomax catback when closed, then just through the moroso muffler when the cutout was opened. the motor that i had that setup on never quite got finished and i got a new idea for exhaust (dual exhaust with hedman longtubes and summit chambered mufflers), but this sounds like a good idea to me.

if you want to retain your cat. i would suggest a high-flow cat, then splice a dynomax bullet or moroso spiral(my choice) into your I-pipe, then have the cutout after the muffler and dumping right in front of the rearend.

i still think that for absolute power with this type of setup, you should put the cutout(s) before the cat and run open exhaust. and i am not one for open exhaust on any car. i race with the NSCA and we are required (for most classes) to run through mufflers, and i think it's a great rule.

McCord makes an electric cutout called the "powerplate"

http://www.mccordcg.com/mpp/mpp.htm

check it out. there's alot of cool pics on that site too that may give you some ideas. i think that you may need to get up under the car some though and get a better aquainted with the under-side of the car.

 

cause you know a V6 really needs a cut out...

 

Mine did...all depends on what you are doing with it...I gain some HP # with the cut out open!

 

i suppose that 5hp is worth the fabrication?

 

Well any gain on a v-6 with about 134rwhp is a big deal...as the dyno guy said its all in the percentages...a 300hp car might gain twice that, but be the same percentage...
There for, it is an equal gain...

Plus right before the darn cut out there is a cink bend (need mandrel bends!). I'm sure when I fix that and clean up the cut out insides, it will flow more...honestly I was not sure it would do anything...

I just looked the numbers on the dyno sheets again...I got even more on the HP then I remembered...and some torque #s...here is the actual numbers from my site...

Sorry!

 

to answer to this and your other post. ithink that your car will benefit from a 3" system more than a cutout. and it will sound way better too...

 

84 custom has a sweet cutout, its electric. I was gonna do a cutout buts it way to loud!