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Old 03-02-2010, 02:46 PM   #1
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Default Noob downpipe question

So, when I bought my turbo kit, I unpacked it, checked it for damage, then repacked it for storage. I knew it'd be a while till I could start the actual build.

After I moved a few months ago, I decided to unpack it again, lay it all out as motivation to get the rest of what I need. And I noticed something that I hadn't noticed in the seller's pics (where it's clearly displayed) or the first time I unpacked it:

The downpipe doesn't have a flange on the exhaust end. Just a bare pipe.

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So, do I need to order the flange from BEGi and have a muffler shop weld it back on? Or would it be smarter to save a little more and just have someone fab up a full 3" exhaust all the way back?
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Old 03-03-2010, 10:18 AM   #2
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Nobody?
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Old 03-03-2010, 11:03 AM   #3
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Looks like they were using a slip-type connection from how shiny the ss is at the end. The decision is really up to you. You could have an exhaust fabbed up around a slip connection, or you can add the flange. Either way will have the same results. If you're going to be running a cat, having the flange would make it a little easier to swap it out for a test pipe if you want. But definitely vote to install a 3" exhaust.
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Old 03-03-2010, 11:05 AM   #4
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3" exhaust. I went 2.5 originally, and I kick myself all the time for it. Maybe consider calling Enthuza to discuss options.
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Old 03-03-2010, 11:12 AM   #5
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Damn. I was mentally planning on putting up with the stock exhaust till later on, rather than an up front cost just to get running. Appreciate the confirmation, looks like I'll be waiting till I can afford a full 3" setup.

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Old 03-03-2010, 11:21 AM   #6
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I just upgraded from a 2.5" to a 3" (with longer magnaflow = quiet) and am glad I splurged on it.

For my old setup I'd had a local shop weld up a flange for me, and built an O'Reilly u-clamp special off of it, with a 14" dynomax. I hated every day of it. It was obnoxiously loud, took four adjustments before nothing rubbed/scraped, constantly developed leaks...etc. When I say loud, I mean I was glad my commute to school is through farm country because it sounds like a crop-duster.

It did open up the breathing though, which was why I jumped the gun on it last fall. Spool improved a little, and picked up about 20bdhp. Big difference in driving.

I had Abe (ARTech) build me a custom 3" with the popular 22" Magnaflow. He did a lot of little things I wanted done, like a flex section after the downpipe, a conical step up from dp diameter, exact bends/routing I wanted, which wasn't easy, and a v-band clamp at the axle to make it easy to remove the midpipe etc.

It's amazing.

1. Quiet, but roars when you step on it.
2. Solid sound.
3. No leaks, no gassy smells.
4. Super easy install. Honestly took 5 minutes to hang, bolt, connect. My flex-tube/coupler/u-clamp monstrosity took me about 6hrs on two seperate tries to fit up.

You don't know what you're missing til you've got it good.

Oh yeah, he NAILED the tip placement, and it looks awesome with the slant-cut 3" SS pipe sticking out. I'll take you some pics on a clean day.
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Old 03-03-2010, 11:31 AM   #7
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Quote:
Originally Posted by gospeed81 View Post
...and picked up about 20bdhp.
Butt dyno horsepower?

Good stuff...I'm really not that upset about it. I just thought my list was down to:

1. Megasquirt
2. WB O2

And now it's:

1. Megasquirt
2. WB O2
3. Exhaust

Filing my taxes soon...can't wait for that first-time homebuyer incentive.
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Old 03-03-2010, 12:53 PM   #8
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Get that 3" exhaust...don't cheap out on a 2.5.
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Old 03-03-2010, 01:05 PM   #9
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Since it seems his questions are answered, and instead of starting a new thread...

How does everyone feel about a car w/ a 2.5" mandrel bend exhaust, no cat? Would it be similar in power to a 3" w/ cat?

I ask because the v-band on the turbo was 2.5" and the ghetto downpipe the car came with needed repair. Instead of stepping it up to 3", I just finished it out with 2.5" mandrel sections band clamped together after the downpipe/flex pipe.

EDIT: I have a cutout also, that I was tempted to weld into the exhaust, and I still might.
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Old 03-03-2010, 01:14 PM   #10
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Quote:
Originally Posted by Project84 View Post
Since it seems his questions are answered, and instead of starting a new thread...

How does everyone feel about a car w/ a 2.5" mandrel bend exhaust, no cat? Would it be similar in power to a 3" w/ cat?

I ask because the v-band on the turbo was 2.5" and the ghetto downpipe the car came with needed repair. Instead of stepping it up to 3", I just finished it out with 2.5" mandrel sections band clamped together after the downpipe/flex pipe.

EDIT: I have a cutout also, that I was tempted to weld into the exhaust, and I still might.
I'm currently running a 2.5" catless exhaust. 1 resonator, 18" magnaflow at the end, stock exit location. I have to say...I feel like I'm giving up a little bit. Not so much in peak power, because I doubt that I'm over-flowing the system I have, but in terms of boost threshold and area under the curve, I think I'll pick up some.

And...Its boring. It sounds good, but I want something that doesn't sound like a slighty louder stock miata. Pretty soon here I'll be going with a 3" catless, 1 large Vibrant resonator, and a pipe out the drivers side w/ a cut bumper. Why be subtle
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Old 03-03-2010, 01:19 PM   #11
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No resonator under my car, just 2.5" all the way back to some big *** carbon fiber knockoff fart can. I can't speak for how it sounds, only had it running twice and that was open dump.

If it weren't for clearance, I've always wanted an exhaust that exited in front of the rear tire. I still might look into this if the car sounds like ***. Toss a resonator under the driver's seat and dump it by the rear wheel.
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Old 03-03-2010, 01:27 PM   #12
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Quote:
Originally Posted by Project84 View Post
If it weren't for clearance, I've always wanted an exhaust that exited in front of the rear tire. I still might look into this if the car sounds like ***. Toss a resonator under the driver's seat and dump it by the rear wheel.
What, like this:
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Old 03-03-2010, 01:31 PM   #13
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Bingo.

There's room? My exhaust runs high up inside my driveshaft tunnel. I thought putting it down and out would expose it to being crushed on speed bumps and what not. Mine will be a street car/SCCA car. The car has Tokico's and some lame *** drop springs.
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Old 03-03-2010, 02:10 PM   #14
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I think that power isn't really lost under a certain threshold. The 3" exhaust would help spool a tiny bit more, and start to make a difference in power as you get closer to 250whp or more.

At 200-220whp the difference in power, if any, between my old straight open and catless 2.5" setup and the new, quieter 3" setup (still catless) is minimal. I did buy it though with plans to get closer to 300whp, where it's going to make a big difference.
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Old 03-03-2010, 02:12 PM   #15
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Quote:
Originally Posted by Jeff_Ciesielski View Post
What, like this:
That is sick! I cant wait to see that car in person. I've been thinking about how that might be possible in my head for a year since seeing an SRT4 at the track with it.
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Old 03-03-2010, 02:23 PM   #16
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Quote:
Originally Posted by wayne_curr View Post
That is sick! I cant wait to see that car in person. I've been thinking about how that might be possible in my head for a year since seeing an SRT4 at the track with it.
That car seriously melts my face. When we went on a drive last weekend, it didn't matter how hard I tried, he just walked away from me. Also, the MASSIVE fireballs that shoot out are ****.
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Old 03-03-2010, 02:27 PM   #17
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Quote:
Originally Posted by Jeff_Ciesielski View Post
That car seriously melts my face. When we went on a drive last weekend, it didn't matter how hard I tried, he just walked away from me. Also, the MASSIVE fireballs that shoot out are ****.
Man I really wish I could make my car stop spitting flames. Its melting the ***** out of my bumper.

Is there a build thread or more details somewhere on that car?
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Old 03-03-2010, 02:33 PM   #18
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Quote:
Originally Posted by wayne_curr View Post
Man I really wish I could make my car stop spitting flames. Its melting the ***** out of my bumper.

Is there a build thread or more details somewhere on that car?
Not that I know of, he keeps pretty hush hush on the boards. I'm sure we'll be doing another drive soon and perhaps we can make this one up north so you can join us.
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