Anyone running short exhaust/no muffler?

[v8s_are_slow]

I'm wondering if anyone's running a really short exhaust on their car. Heck, maybe just the downpipe and nothing else? If so, wondering how the sound is. If not a short exhaust, how bout just taking off the muffler?

I have an ATR exhaust with a straight pipe and it's already LOUD (which I like though) but pondering dropping the catback to allow my T-67 to spool a lil more freely. Just wondering how well this would be for driving on the street with the exhaust and all. Dunno how hot it'd make it get under the car. It's not a daily driver by any means so it's not like I'd have to listen to it all the time.

Any opinions? And sorry if this has been discussed a gazillion times. Just didn't know what to look for.

 

[Mike1992]

I run an Apexi downpipe + catback and the rear section after the axle was stolen so I run it open pipe dumped under the axle. Sounds good to me and I've been driving it like that for about a month now.

 

[brute]

I'd suggest an electric cut out. You can buy them at places like Jeg's, Summit, JC Whitney, etc.

To my understanding, running with an open downpipe can create boost creep.

 

[TSIAWDTalon]

I am running 3 inch right off the downpipe to a straight thru muffler, then dumped right before the rear end. Kinda annoying on long trips but not bad just driving easy through town.

 

[pneumo]

I did something like that. I had a full 3" exhaust with a test pipe and an ATR catback. Then I took the muffler off, removed the pipe that goes under the axle, and reattached the muffler just in front of the rear axle while adding a 3" turndown on the end so exhaust didn't blow directly on the CV joint and gas tank. The slip fit joints make it easy, but I still had to fabricate two mounts so it didn't bang on the driveshaft everytime I hit a little bump. It saved 13 pounds, too.

The sound was OK for street driving, but it's unbearable for long cuising on the freeway, especially above 70 mph. It was only a little louder than the standard ATR catback. At the track the sound has a very crisp, ripping quality to it. Definately the sound of power. I really liked it at WOT
Here's a pic I posted in another thread along with some unrelated comments. http://www.dsmtuners.com/forums/showpost.php?p=50427348&postcount=326

 

[xveganxcowboyx]

I run a full 3" exhaust with no muffler and it's reasonably quiet (only a light drone at highway speeds). It's got a high flow cat and 24" resonator. Most importantly, it's got 180 degrees of bend including the down pipe.

 

[topstreet]

My exhaust turns down at about the rear seats. I get a little bothered by it in the car because of the bass of it. I have let friends drive the car so I could listen and it is definitly louder in the car. I was thinking about making a turn down off the turbo right to the ground. I have not done this yet though.

 

[v8s_are_slow]

Wondering what it'd be like to maybe put a turn down right after the straightpipe I have without the muffler.

Another thing I've thought about is maybe making a side exit exhaust that comes out right in front of the left rear tire. Can't remember how much room there is under the car to even manage this though. Thought about maybe getting a 3 inch pipe that's curved but get it squeezed in a vice or something to narrow it down some. I figure it'd still be 3 inches but the shape would just be changed some and it'd help with clearance. I dunno.

For you guys running no muffler, how loud did it make the turbo spool? That's one sound I really love to hear. Kinda like when I hear a diesel pickup truck driving by and the turbo sound is heard thru the exhaust.

Pneumo, did it make your turbo spool any louder after what you did or just make the car a bit louder? Not sure I wanna hack up my catback incase I decided I wanted to throw it back on the car.

Anyone else have any pictures? Videos? Vids would be really nice. Thanks!

Scott

 

[v8s_are_slow]

To my understanding, running with an open downpipe can create boost creep.

Not sure how easily this would happen with a Tial 44mm wastegate.

 

[pneumo]

That's the one thing I REALLY liked about the short exhaust- I could hear the turbo through the exhaust! Yes, it was like a big rig turbo sound, also like the sound an SRT4 makes. I played with it and found out that I could hear it on the freeway above all the other noise. If I backed off the throttle slightly the turbo would gradually spool down. Very cool!

I wouldn't squash the exhaust into a flat oval, it would reduce the flow area and might restrict it a little.

 

[v8s_are_slow]

Thinkin I'll try and drop the catback and when I have the time I'll get a 3 inch turndown section and weld it to a 3 inch flange that'll bolt up right after my straightpipe Wondering how nicely the T67 would sound thru that.

 

[nightspeed87]

My exhaust turns down at about the rear seats. I get a little bothered by it in the car because of the bass of it. I have let friends drive the car so I could listen and it is definitly louder in the car. I was thinking about making a turn down off the turbo right to the ground. I have not done this yet though.

mines too sounds louder inside

Another thing I've thought about is maybe making a side exit exhaust that comes out right in front of the left rear tire. Can't remember how much room there is under the car to even manage this though. Thought about maybe getting a 3 inch pipe that's curved but get it squeezed in a vice or something to narrow it down some. I figure it'd still be 3 inches but the shape would just be changed some and it'd help with clearance. I dunno.

My mechanic/tuners exhaust is like this...
Go here- www.gearracing.com

Go to pictures and his car is the grey 1g at the bottom under the pics of all the engines and you can kind of see his exhaust sticking out by the passenger rear tire... ( Oh and by the way the red 4g63 above that is my engine )


And im bout to run 3 all the way back and right where the muffler is suppose to be attached just have no muffler because Im tired of the muffler I have now, im going to just chop it off and go without it till i figure which one i want.... Hopefully this wont b too loud.... I dont like a lot of obnoxious noise.

 

[v8s_are_slow]

Wish he had pics of the exhaust from underneath. I'd wanna run mine on the left side though. Also, I don't think I'd really want it in front cause when I was in the Army and riding in the old 2 1/2 ton trucks, the exhaust would exit in front and I was about deaf. Screw that!!!

 

[nanokpsi]

I run a turn down right under the car almost where the flex section would be. It is loud! I am going to have it extended and run a racing/bullet muffler dumped closer to the back. Here it is at idle. It also shows it from underneath.
http://videos.streetfire.net/player.aspx?fileid=EB6F535E-79E4-4B4C-83B1-6918B2FF14CF

 

[danny_l_2005]

I got a 3" exhaust with no cat or muffler, and i hear my turbo spool and spool down through the exhaust. It doesn't bother me, i guess i got used to it. Plus i see people looking at my car like this WTF

 

[v8s_are_slow]

I run a turn down right under the car almost where the flex section would be. It is loud! I am going to have it extended and run a racing/bullet muffler dumped closer to the back. Here it is at idle. It also shows it from underneath.
http://videos.streetfire.net/player.aspx?fileid=EB6F535E-79E4-4B4C-83B1-6918B2FF14CF

I can definately hear the turbo spooling. That exhaust looks badass!!! By chance have any vids of it under acceleration or from inside the car just tapping the gas? My motor is out and I've been running into problem after problem with the new setup I have but should be finally good to go this Tuesday. Really thinkin about just dropping the catback and the straightpipe and then have a turndown with a flange on it to bolt up to my downpipe (so I can put it back like it was if I wanna). Would be nice to hear that thing from all aspects though. We all know it gets louder when you hit the gas

Thanks for the vid posted thus far though.

 

[nanokpsi]

I can definately hear the turbo spooling. That exhaust looks badass!!! By chance have any vids of it under acceleration or from inside the car just tapping the gas? My motor is out and I've been running into problem after problem with the new setup I have but should be finally good to go this Tuesday. Really thinkin about just dropping the catback and the straightpipe and then have a turndown with a flange on it to bolt up to my downpipe (so I can put it back like it was if I wanna). Would be nice to hear that thing from all aspects though. We all know it gets louder when you hit the gas

Thanks for the vid posted thus far though.

I don't think we got any of my later dyno runs on film. It is definately way to loud. It wouldn't be as bad just a few feet further back. Just regular driving conversation is difficult in the cabin. I wanted to add a flex section and run it into one of these so it would dump a little closer to the rear end http://store.summitracing.com/partd...4219&N=700+302177+4294791977+115&autoview=sku

I'll post some vids when I get it running again. Polk should have my longblock finished this week.

 

[nightspeed87]

probably makes it worse with the sound bouncing off the ground since of how you have it aimed... Im 3in open dp right now ... Havent heard it yet since im in the middle of a rebuild, but once i drop my 6bolt in in about 3weeks will know how it sounds...

I wonder what exactly determines a cars exhaust note ( like why do hondas sound how they do, or why do mustangs sound so deep and aggressive.. )
I imagen it all has to do with the amount of combustion the car produces... I also have learned turbo cars are generally quieter than n/t engines because of the turbo being mounted in the exhaust it interferes with the exhaust sound some how?!?! ( A n/t on open dp is louder than turbo engine on open dp for example )
Ive heard a 1g guy on open dp before it his car wasnt that loud to be honest, just very raspy and deep and aggressive sounding, but wasnt loud even when he got on it... But then ive heard another 1g talon with open dp and his car was screaming loud.... Any clue to why is that.

 

[staticbrainwash]

A turbo acts as your exhausts backpressure, therefore we can run big and get no issues.

Exhaust note is usually determined by #1, Displacement. Hondas running a 1.6 or 1.8 with a big fart can are going to sound a lot different than a v8 with straight pipes.

Pipe size also makes a big difference. I have a 3" exhaust with one bullet muffler. My buddy has stock exhaust with no muffler and no cat. His is a lot diffferent sounding than mine.

Turbo's make exhaust quieter and lower typically (espically comparing NA and turbo dsm's), and i believe exhaust routing can make a difference too. For example, the dumps will sound a bit different than my car with what is esentially a 3" straight pipe, or a car with an oval can muffler and a HF cat.

So a lot of factors. I imagine turbo size might make a difference too, but i'm not positive.

What wouldn't be bad would be to put in a flange where you want to dump, so you can run a catback-ish system for the street, or pull it down and put in the turndown for the track.

 

[GstRacer]

i have the electric cut out and i think it's pretty nice too be able to have the bennys ofrunning open DP at the flick of a switch. but also be able to drive queit when you dont wanna be loud and really fast.

 

[thekellbeast]

Dre used to run a 3.5" exhaust, and to make it quiet enough to drive on the street, he had an exhaust cut-out inline in the system. He had small holes cut in the cut-out's plate, so that's all the exhaust could go through when it was closed. When it was open, it turned sideways so there was no restriction, and he got the full 3.5" exhaust. It was like a remote operated silencer.

 

[Jeff822]

I ran mine with no muffler for a day, it was an Apexi 3" Dp, HKS 3" exhaust no cat with 1 resonator, it was loud, really loud, it sounded like a mix between a Srt-4 at lower rpms and a turbo deisel truck at higher rpms, sounded pretty bad a$$ though.