Custom exhaust
 

A good friend of mine designed and fabricated an exhaust system for me today.

Pictured below are the 5 setups he drew up. He said we could do any of the 5 setups either dual or single exit.
http://i42.photobucket.com/albums/e3...psastp2p3u.jpg

Option 2 would have utilized a resonator then a Y pipe off the res to the mufflers. Option 3 used a 1 inlet-2 outlet muffler back to two more mufflers

We both chose option 3. He used 3 sticks of 2.5" mild steel piping, two U bends, a Magnaflow 1 inlet-2 outlet muffler, two Vibrant mufflers, and two Silverline tips.

Stock junk removed
http://i42.photobucket.com/albums/e3...pszglth672.jpg

Front pipe section and magnaflow mocked up
http://i42.photobucket.com/albums/e3...psflme2zgq.jpg

A stick on each outlet to get past the diff
http://i42.photobucket.com/albums/e3...psvndnagkr.jpg

Welding
http://i42.photobucket.com/albums/e3...psnf3swm1x.jpg

Vibrants mocked up
http://i42.photobucket.com/albums/e3...psyfrzy7j1.jpg

Silverlines mocked up and my buddy posing
http://i42.photobucket.com/albums/e3...psow1vjvqx.jpg

Love the angle of the exhaust from the side
http://i42.photobucket.com/albums/e3...pscebymfxy.jpg

Nice under carriage shot of the assembly completely mocked up
http://i42.photobucket.com/albums/e3...psx859vtet.jpg

The assembly mocked up and tack welded was then removed to complete the welds
http://i42.photobucket.com/albums/e3...psotwry1pt.jpg

Welding photos
http://i42.photobucket.com/albums/e3...psmdclhvdn.jpg
http://i42.photobucket.com/albums/e3...psyod72ecd.jpg
http://i42.photobucket.com/albums/e3...pskxw0s9z3.jpg

We coated it with a satin grey VHT exhaust paint to help prevent rust. Overall I'm VERY pleased with both the sound and the appearance!

As far as sound: on a scale of 1-10 with a 1 being a bone stock Ford Focus and a 10 being a cammed C7 vette with 3 inch straight pipes I would rate this as a 4.5 on the aggressiveness scale. Stock BRZ exhaust would be a 2.

Idle: sounds exactly like a stock BRZ. Cruise: There was a very slight increase in noise - barely noticeable in the cabin with the window closed. WOT: obviously the most noticeable difference. Louder but not weed whacker sounding, very throaty and nice. When I come off the throttle there is a very nice deep pop sound that I absolutely love.

Performance wise: seems to have gained some mid-range power. Also seems that the horsepower doesn't taper off and the engine pulls nicely from 3.5k to the limiter.

Very pleased with the setup. Cannot wait to get a hold of an OFT to really reap the full benefit of the exhaust.

Video: https://youtu.be/SQKonB9A12c

Looks awesome man! Which magnaflow muffler did you use in the mid pipe? Can you post up a part number? I'm looking at building a similar setup but I'm concerned about space and ground clearance.

I've attached the parts list that we used. All parts sourced from Summit. My buddy had a two winged flange laying around that we used between the header and our assembly.

Note: we bought three U bends but only used 2. We bought two sticks but needed 3.

So, you managed to:
- Create a big sail area under the rear bumper.
- Require everything after the overpipe to be removed to change diff or tailshaft.
- Remove the cat in the front pipe for no performance gain at all.
- Reduce ground clearance behind the rear wheels. I guess Detroit is enough of a ghost town now that you never need to reverse in to parking spots anywhere.

GG. Slow clap.

I guess you managed to do something on the cheap. Oh wait, the stock cat back comes with the car, so if not wasting money was a goal, then that can hardly be considered a win.

It's a bit late to be crapping on about OFT now, if you'd spent 5 minutes to read any of the 4 years worth of content you'd know that any gains on stock tune are a fluke. The car would pull equally hard to redline with a half decent tune on stock catback.

Lmao Wayno you're a savage, at least acknowledge the difference in sound. It seems to have pleased the OP. :D

Well, g0lds , it sure did look like you and your buddy had a good time designing, building and installing your car's exhaust system ...... :thumbsup:

Nice presentation!


humfrz

I got something like your option 4 done... pleased with it in the end, just mine is pretty damn loud.

Just out of interest - did you do headers, cos that's where I got 90% of my gain (with tune of course)... the rest added a bit more, but not the bulk of it.

Hey no worries, not everyone is a fan, can't please everybody and that isn't the end goal, I'm happy with it which is what matters most! I welcome all feedback - positive or negative. :respekt:

Wayno, you make valid points, but:

• I'm not concerned about dropping the entire assembly to service the driveline. Takes all of 2 minutes to remove it, plus I have access to my buddy's hoist whenever so it's not like I'll be wrestling with the assembly on jackstands or anything unless in the case of an emergency.

• Not concerned with the aerodynamics of the setup. It's a straight-thru exhaust with no spaghetti twists and turns and diameter changes like the stock setup had so I think any drag under the car will have limited, if any, affect on performance or mileage. I don't plan on taking it up to speeds where it will cause trouble

• As far as ground clearance, we may have to revisit and make some adjustments because I did scrape it a couple times and scraped big time pulling out of the driveway

• Not concerned with the rear converter, no emissions testing in our state. :happyanim: Eventually all cats will be removed.

As I said, I personally love the appearance of the setup and the exhaust note is absolutely perfect.

PS- Detroit is an awesome city and is making a comeback and Michigan is naturally beautiful! :)

Nice! Yes I am most pleased with the exhaust note. As I said a 4.5 out of 10 on the aggressiveness scale which is exactly where I wanted it to be.

I did not touch the header, I am considering cutting the cats out of the header though once I get my OFT

Interest read. Good job on the custom exhaust!

Just wondering, if front muffler (1 to 2 pipes one) isn't too low? Or it tucks in well?

I will measure the clearance tonight. The rear mufflers are the lowest point on the assembly, affording only 3 or so inches of clearance. Over the winter I may see if my friend can re-visit the rears to achieve more clearance.

I was more worry bout front muffler scraping from going through bumps. iirc several Borla catback owners have this issue.

I myself are thinking of doing my own custom exhaust, thanks this gave me a good view on how to do it :)

It looks good, but mild steel...really?!?
In detroit it's going to be rusted through in 2 years top. The paint won't protect it, it will rust from the inside.