Questions about using exhaust Cut-Outs

[RicciDSM]

the car is a 97 Talon TSi FWD.

Alright so long story short, im too broke to buy a turboback so I was thinking about getting a simple 2.5" exhaust cutout for my stock exhaust. Nothing crazy, not even the electric one. I figured since id have it open like 95% of the time id get the one that bolts shut and its only like $25 on jegs.com

Ok so to my questions. Its 10" long says the website, so where would be the best place to weld it into my exhaust? I was thinking about right after the downpipe's cat, theres a nice space between the cat/resonator to place it, but since its after the cat there wouldnt be much performance being gained from this right? It seems like it would be all noise and no power gains.

Would my best bet be to place it before the cat, on the downpipe? Even if it IS before the cat, should I expect ANY power gains? Or just the obnoxiously loud, orgasmic turbo spool sound?

My main concern is boost creep. I know running open DP will cause boost creep issues, but would an open cutout cause any problems?

Thats pretty much it, if theres any other info I need to know that someone can fill me in on im all ears. I want to order one this week, I just want a little more info on these before I jump on it.



Thanks in advance for any info

 

[turboking15]

I would definatley put it before the cat otherwise it kind of defeats the purpose. As far as your concerns on boost creep i dont have any first hand experience but i would imagine if you are running the stock downpipe to a 2.5 inch cutout i dont see it as being to big of an issue.

 

[standard235]

Delete your cat with the cutout.

 

[RicciDSM]

Delete your cat with the cutout.

Say i went with this idea, would i just straight up cut the cat off and weld in the cutout? is there any o2 sensors or plugs on the cat that i would have to do something with? this would trigger a cel am i right? how would i go about disabling the light if it does come on?

sorry for all the questions im just tryig to get as much info as possible.

 

[black_gst]

MY electric cutout is where the cat used to be it fits perfectly right there. i also have a turn down which is a must so you dont catch your car on fire. i wish i would have taken pics but i didnt... im actually putting a stock catback back on my car so it will look and sound stock with the cutout closed... it is really loud and vibrates the whole cabin.

i bought this one
Welcome to DMH Performance!

its a good unit no problems so far i have had in on the car for about 4 months. i love it!

my car should be up in the air soon ill try to remember to take some pics

 

[Bluefire16]

Put it before the car, and close to the turbo. When i return home i am doing this, i am custom making my DP with a 3" cutout that exits to the side of the car.

^^^ and thats the cutout im going with

 

[RicciDSM]

Hmm thats probably what ill do, place it right where the cat is. Removing the cat will trigger the CEL though right? Im sure I can clear the code with my scanner but will it stay off? Or will it eventually pop back up again since theres no cat on the car?

 

[92_1g]

If your worried about your check engine light you can install this. STMDSM - Check Engine Fix- Rear o2 Sensor

It moves your o2 sensor out of the exhaust stream just enough to fool your ecu into thinking you have a cat installed. You would have to install the cut out past the out sensor so it would still have exhaust flow. If you still want to run a cat could run it after the dump and o2 sensor.

Paul

 

[Ppayer38]

As far as The fix for the CEL just go buy SparkPlug nonfoulers from Advance or AutoZone... Way cheaper and does the same job.
I am thinking about doing this also and going to try and put it right after the 90deg bend in the DP. At that point I dont believe it will matter if it is a 2.5" or 3" exhaust cause it is so short.

would love to see some pictures of these things installed on a DSM

 

[Jeff99GS]

In my opinion every DSM'er should have a Cutout!! It is the best mod I have ever done to my Talon. I run a stock cat back with a 3.5" downpipe and a 3.5" E-cutout...its BADASS!!! I can go from a stealthy stock pipe sound...to LOUD ass turbo spooling madness...It's GREAT! When I have the cutout closed I can pass emissions test and not sound like a fart mobile. When the cutout is open it sounds nice! It's not even that loud... all you can hear is Turbo whine! If I even touch the throttle you can hear the spoolin. When I go WOT it gets incredibly loud and wicked sounding.

I have yet to test the track differences, but I can tell it's WAY faster with the cutout open (for obvious reasons)
When I ran a 13.4 I had just the stock exhaust /cat and a 16g.

As far as boost creep, you will get it if you have an unported internal wastegate. I switched over to the HY-35 with External gate and I have NO boost creep what so ever!

Here is a short video...Its not the greatest but you get the idea. With the cutout open at idle it almost sounds like a V8 idling! I made the e-cutout myself out of a GM 3.5" electric throttle body. They are all over ebay for like 30 bucks. It works PERFECT every time and it seals great.

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[RicciDSM]

Jeff99GS, trust me ive seen those videos plenty of times on youtube . Looks great! Im going with the manual cutout for now, then later down the road ill be getting the electric valve but ill keep that in mind.


Im running stock turbo/wg and all that good happy stuff. All ive got done to the car is an intake, uicp, and blow off valve. Thats why I ask about boost creep issues. Im just curious if id have any issues running stock turbo etc etc and have to look into getting a MBC.

I havent really been under my car but I do have a general idea of how our DP's are setup. How much room is there before the cat on the DP? The cutout im buying is 10" long so thats all ill need to have it welded right in.

Also, how much power should I be expecting by having the open cutout before the cat? Or would I get more power by putting it in place of the stock cat? I know im not expecting CRAZY power but will I should definitely notice a difference correct?


Oh yeah, and say I remove my cat to place the cutout in, what would I do with the O2 sensor until I go and do the spark plug non fouler (which is a great idea btw) ? Would I just leave it hanging or something? Or is our O2 sensor BEFORE the cat and not ON it?

 

[hurricanecris24]

im thinking of doing this
http://www.dsmtuners.com/forums/articles-intake-exhaust/363787-3-flow-go-stock-show-slow.html

 

[RicciDSM]

im thinking of doing this
http://www.dsmtuners.com/forums/articles-intake-exhaust/363787-3-flow-go-stock-show-slow.html

I was also but how restrictive can the stock muffler possibly be? If anything, placing the cutout before the cat or replacing the cat will add more power than right after the muffler. I just dont know where exactly I should place it

 

[RicciDSM]

Well I made the move and bought everything I need.

(1) Cutout from JEGS ($30)

(1) Pack of Spark Plug Nonfoulers ($5)

(1) Tube of Thread Lock ($2)

(2) 2 1/2" to 2 1/4" Exhaust Adapters ($10)


Should be installing myself on Sunday. This could either turn out to be the best $47 exhaust ive ever made for myself, or become a horrible sounding pile of S***

Either way Ill keep everyone updated on how things turn out, and will possibly make a nice write-up about it

Thanks for the help everyone! Will keep you all posted!

 

[Car_guy_09]

jeff how do you go about wiring up that throttle body as a cutout? thats pretty damn cool

 

[RicciDSM]

/\ I second that.

Another question...Will running no cat with cutout on the stock downpipe cause any problems to my car whatsoever? Since the car isnt tuned or anything?

 

[Calan]

jeff how do you go about wiring up that throttle body as a cutout? thats pretty damn cool

And how well does it handle the heat?

I would think that after some time, there will be leakage issues or a hard failure, due to the much higher heat that the TB will be seeing vs. what it was designed for.

 

[Jeff99GS]

And how well does it handle the heat?

I would think that after some time, there will be leakage issues or a hard failure, due to the much higher heat that the TB will be seeing vs. what it was designed for.

It's been on my car for 2 or 3 years and 10,000 miles, still works perfect! The gears are made of steel, the body is made of aluminum and the throttle blade is made of Brass. I took all the other bullshit off of it. So there is nothing that would be affected by heat at all. You have to remove the spring inside of it that makes the blade shut automatically.

As far as the wiring is concerned I removed all the electronics and wired to the motor directly. Then you need a switch that reverses polarity (like a sunroof switch) this allows the motor to go both ways. Its very simple.

 

[RicciDSM]

UPDATE!

Well everyone, I had the cutout installed. And all I really have to say is...WOW! I LOVE IT!

<a href="http://s528.photobucket.com/albums/dd329/theguy6661/1997%20Talon%20TSi/?action=view&current=DSCN0818.jpg" target="_blank"><img src="http://i528.photobucket.com/albums/dd329/theguy6661/1997%20Talon%20TSi/DSCN0818.jpg" border="0" alt="Photobucket"></a>

I took it to an exhaust shop to have put on. Cost me $45 to cut out my old cat, and have the cutout welded in with some extra piping.

Let me start off by saying, this exhaust setup is LOUD. Definitely not for the daily driver. Half throttle shakes the whole car and vibrates your ass . Personally, I love how loud it is and doesn't bother me one bit. I noticed a little increase in boost also. Before the exhaust was installed, my spike was 14-15 and holding at 11psi, after the cutout was installed my spike is close to 20 but slowly drops to 13-14.



My question is, should I be worried about the spike being so high?



Also, Ill try and get some decent videos tomorrow for everyone to hear.

 

[RicciDSM]

Another thing...Check Engine Light. Even after taking the cat off and running open cutout, I have yet to see a CEL (knock on wood). Even though, if it does come on ill just do the spark plug nonfouler idea. I mean I might as well, I already bought them -_-

 

[dsmdeliveryboy]

Another thing...Check Engine Light. Even after taking the cat off and running open cutout, I have yet to see a CEL (knock on wood). Even though, if it does come on ill just do the spark plug nonfouler idea. I mean I might as well, I already bought them -_-

It will take some time for it to throw a CEL if it does, and yes I would be worried about it spiking to 20psi without a logger or nothing to tune with.