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So I finally got around to making my own exhaust. Its probably not the best designed housing off the turbo but it works for me. At this stage I'm not looking to fabricate any more but I may do so when I have a bit more time on my hands. Anyway, on to the pictures.

Here's the flange I started with. It was sourced from the same supplier as Jake's O2 housing from a few years ago BMC Racing Products.



The jig I made from the stock housing









The custom O2 housing.







As I said, it's probably not the best designed but I was up for a challenge. Its 2 1/4" off the flange into a 3" reducer with a 1 3/8" separate wastegate. All the exhaust places I went to I couldn't find a bend tight enough so I lobster backed/pie cut to make a tighter radius.











Here's the pics of the exhaust I fabricated up. Its all 3" stainless tig welded together.

Don't mind the heat marks on the downpipe. I hade to get an extra 5mm clearance so the bottom exhaust bracket would line up.





Magnaflow resonator.



This was the fun part. When I say fun i mean pain the ass, again needed a little heat to get extra clearance.



Magnaflow single 3" to dual 2 1/2"











You might be wondering why I used a few flanged sections. I did it this way for a couple of reasons, 1. it was easier to handle and weld. 2. if I ever decide to take it to the track I can unbolt the cat and resonator and bolt in a straight tube section.
 

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Finally here are the pictures of it on the car.

The clearance of the AC was important. I had to move the oil dipstick 45 angle.













The downpipe and under the car.











 

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I forgot to mention I also threw on the T-bird turbo I had laying around from a few years ago.
 

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As I said, it's probably not the best designed but I was up for a challenge. Its 2 1/4" off the flange into a 3" reducer with a 1 3/8" separate wastegate. All the exhaust places I went to I couldn't find a bend tight enough so I lobster backed/pie cut to make a tighter radius.
Thats some impressive work for sure. Having a tight radius 2.25" pipe, merging into the 3" expansion and the wastegate pipe, all integrated into the O2 housing??...thats a lot of packaging into a small space. Best design?....from a "man, that looks like a PITA to build" standpoint...maybe not the "best" design (I wouldnt do it* ), but you have pulled it off extremely well...Kudos to you. So call it B for PITA design, A+ for execution :)

*For my own project, I also used an expansion (2.5">3"), but I placed it on the downpipe...and I didnt even have the A/C unit and its space restrictions to deal with. You sir, are a nutter......but then your name is CraZyOne, so I suppose thats to be expected ;)

You might be wondering why I used a few flanged sections. I did it this way for a couple of reasons, 1. it was easier to handle and weld. 2. if I ever decide to take it to the track I can unbolt the cat and resonator and bolt in a straight tube section.
I actually was thinking...wow, that exhaust system looks fantastic...but waaay overbuilt. Do you have requirements to maintain stock number of mufflers/length/exit of the exhaust system? The reason I ask is that theres a lot of weight that could be removed with little sound penalty. As an example, my 88GT has no muffler or resonator, just 2.5" piping from the catalyst out (the most it registered was @84db/50ft, (2nd gear WOT) if i recall correctly). The autocross racer was built with a minimal and lightweight exhaust system. It uses 3" thinwall stainless piping, no catalyst, no resonator, 3" in/outlet (straight through) racing muffler capped with an aluminum turndown that terminates under the car, right behind the front seats. Even at that, I expect it to test at less than 92db/50ft.

Gavin
 

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Question, did you drive the car yet, and if so, how is the rear axle piece when you go over bumps? I've got 3" turbo back and coilovers set pretty stiff, practically solid motor mounts, and 17" low profile tires. I'm thinking all that other shit has more to do with it than the 3" pipe itself, but when I go over bumps, the pipe hits the rear cross member. I tried adding a hanger and it made it a lot better, but it seems there is just no room for that damn huge pipe over the rear axle.
 

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Thats some impressive work for sure. Having a tight radius 2.25" pipe, merging into the 3" expansion and the wastegate pipe, all integrated into the O2 housing??...thats a lot of packaging into a small space. Best design?....from a "man, that looks like a PITA to build" standpoint...maybe not the "best" design (I wouldnt do it* ), but you have pulled it off extremely well...Kudos to you. So call it B for PITA design, A+ for execution :)

*For my own project, I also used an expansion (2.5">3"), but I placed it on the downpipe...and I didnt even have the A/C unit and its space restrictions to deal with. You sir, are a nutter......but then your name is CraZyOne, so I suppose thats to be expected ;)
Surprisingly it wasn't all that difficult to fabricate, it just took quite some time. Being a boilermaker/fabricator by trade I guess I'm used to doing projects like this. I wanted to keep the housing as close to in dimensions as the stock one with the options of going either 2.5" or 3". The jig I made has slotted flange holes for both. The 2.5" option was planned for those who want a direct bolt in to the existing stock exhaust if they need to wait for the rest of the exhaust for any reason. (be it money, time etc)

I actually was thinking...wow, that exhaust system looks fantastic...but waaay overbuilt. Do you have requirements to maintain stock number of mufflers/length/exit of the exhaust system? The reason I ask is that theres a lot of weight that could be removed with little sound penalty. As an example, my 88GT has no muffler or resonator, just 2.5" piping from the catalyst out (the most it registered was @84db/50ft, (2nd gear WOT) if i recall correctly). The autocross racer was built with a minimal and lightweight exhaust system. It uses 3" thinwall stainless piping, no catalyst, no resonator, 3" in/outlet (straight through) racing muffler capped with an aluminum turndown that terminates under the car, right behind the front seats. Even at that, I expect it to test at less than 92db/50ft.

Gavin
Unfortunately in the nazi state of Victoria where I live, where you can be fined for going 3km over the speed limit, yes, there are some restrictions. It is illegal to run without a cat and massive fines can be had if caught. This brings me to the next point, sound. A loud exhaust attracts attention from the police and if they think its too loud they'll send you to get tested for dB reading. Fail this and you get slapped with a unroadworthy until its fixed.

That looks like an amazing job. Can't believe its 'backyard'.
Thanks mate. Its amazing what you can do with a tig welder in your backyard ;)

Question, did you drive the car yet, and if so, how is the rear axle piece when you go over bumps? I've got 3" turbo back and coilovers set pretty stiff, practically solid motor mounts, and 17" low profile tires. I'm thinking all that other [shizzle] has more to do with it than the 3" pipe itself, but when I go over bumps, the pipe hits the rear cross member. I tried adding a hanger and it made it a lot better, but it seems there is just no room for that damn huge pipe over the rear axle.
Yeah I've been driving it for about a week now. I did have to make a few little adjustments to the clearance as you can see by the heat marks in the bends. I have between .5" - 1" of clearance from the rear crossmember and I never hear it hitting. The hangers I have are pretty stiff and allow for very little movement and I also added the bottom exhaust bracket just before the flexpipe that gets bolted to the subframe. Its actually quite difficult to move my exhaust in any direction and the rubber hangers are acting more like vibration dampers.
 

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Great work, I'm impressed. I like the fact you lobsterbacked the dump, yet tidied up the welds. It makes it look all the more impressive.

Also I'd be interested to see how much thermal expansion you have in your exhaust. When I did mine it grew in length by about 15mm.
 

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TOP - TOP work.

In fact - add some HPC coating to it. Mod the factory heat sheild and it's perfect.
90% of an inspection station won't see it.

It will be loud - Well by EPA/Vic road standards - can't remember the limit but it is higher then NSW.

The only way IMO or I have found in NSW to cut back the noise enough to at least pass most questionable issues, is large middle expansion resonaotor/muffler. I run it and original rear to pass 90DB in NSW but it is a massive rear end restriction but you do go sight unseen.
RBT in NSW is where the list it and then send you the letter later in the week.

It's nice peice of work. If you ever decide to sell that one to build another let me know. Right price I'll buy it. Could not be stuffed doing my own. I would not of done it any other way either.

Would of thought it would clear NO issue in the rear. on a 4WS 3inch is tight but 2WS you can easily fit 3.5 inch pipe in with room.
 

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Nice work....

You could start up your own exhaust shop...
 

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Unfortunately in the nazi state of Victoria where I live, where you can be fined for going 3km over the speed limit, yes, there are some restrictions. It is illegal to run without a cat and massive fines can be had if caught. This brings me to the next point, sound. A loud exhaust attracts attention from the police and if they think its too loud they'll send you to get tested for dB reading. Fail this and you get slapped with a unroadworthy until its fixed.
Unfortunately this is a tactic we in California are very familiar with. There are sound limits on mufflers (95dba/50ft I think), and I am fine with that.....what I am not fine with is that one can simply get pulled over for "sounding too loud". You see, the highway patrol do not have portable decibel meters. If you get pulled over for speeding, the cops just cant say.."heres a speeding ticket because I thought you looked like you were going too fast". Without some sort of verifiable proof (radar, laser, even pacing a car for a distance and then using the cruisers tire diameter and gearing to accurately calculate speed), the ticket would be dismissed by the courts so fast it would make your head spin......but yet they can do that for sound...how the hell does that work :confused:

Ok, now you have this so-called a "fix-it-ticket" for sound. You can either pay the fine or get it dismissed (because you know you are in compliance). To do so you have to take the vehicle to an authorized referee station to prove the issue has been fixed(or was fixed the whole time)....there is a $10-$25 fee to get tested. So in other words...it doesnt matter if you are innocent or guilty, you STILL pay a fee. F-ing highway robbery is what it is :mad:

Gavin
 

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Very nice..
I like the whole system.

Glad to see you made a dump pipe for the stock turbo.
No many both due to upgrading.
 

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Unfortunately this is a tactic we in California are very familiar with. There are sound limits on mufflers (95dba/50ft I think), and I am fine with that.....

Gavin

Gavin you have it easy - most countries it's 95DB Japan - Cali Us UK I think is 98DB.

but here in NSW Australia and some other states. but NSW is crazy POst 1986 model cars it's 90DB - which to give you and idea how hard it is to pass.

a Stock GT MX-6 will make about 86DB. I had to use a stock original rear muffler to get 89.8DB on my EPA readings.

All PRe 1986 cars only have to make 96DB. Which is ALOT easier.

Lucky enough they only do a Rev up to 3/4 rev range.

but our newer system is if A officer gives you a ticket and you dispute it. They pull your file. - Yeah car has file with state Roads system with photos and drawing of the Emissions and exhaust. So if you make changes they know then the fine you for it.

More and more people I know now are either going full stealth valves or Just buying AMG's or HSV's or stock Modded hot rods. It's alot of pain these days.
 

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Looks great! Did you get my PM regarding the 5 bolt flanges? My friend said he'd be willing to ship you some. How tough was it to get the nut below the wastegate?! You have even less room than I do on mine.
 

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interested
 

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Minor conversation detour......


Unfortunately this is a tactic we in California are very familiar with. There are sound limits on mufflers (95dba/50ft I think)
Gavin you have it easy - most countries it's 95db Japan - Cali Us UK I think is 98db.

but here in NSW Australia and some other states. but NSW is crazy POst 1986 model cars it's 90db - which to give you and idea how hard it is to pass.

a Stock GT MX-6 will make about 86db. I had to use a stock original rear muffler to get 89.8db on my EPA readings.

All PRe 1986 cars only have to make 96db. Which is ALOT easier.
I was curious about this and decided to check on my memory about our State regs for sound here in california....

V C Section 38370 Noise Limits

Vehicle Code said:
Section 38370 Noise Limits.
(a) The Department of Motor Vehicles shall not identify any new off-highway motor vehicle, which is subject to identification and which produces a maximum noise level that exceeds the following noise limit, at a distance of 50 feet from the centerline of travel, under test procedures established by the Department of the California Highway Patrol.

(1) Any such vehicle manufactured before January 1, 1973..........................................................92 dBA

(2) Any such vehicle manufactured on or after January 1, 1973, and before January 1, 1975...........88 dBA

(3) Any such vehicle manufactured on or after January 1, 1975, and before January 1, 1986...........86 dBA

(4) Any such vehicle manufactured on or after January 1, 1986....................................................82 dBA

(b) The department may accept a dealer's certificate as proof of compliance with this section.
Whaaaaaa????? :confused::confused::confused:82[email protected]?

Thats number is so absurd its almost comical. Theres a whole host of brand new...off the showroom floor...unmodified vehicles that wouldnt be able to meed those requirements. Just off the top of my head would be any of the new V8 Ford mustangs (Coyote motor). Might as well add any car with a chevy LSx variant as well. The old Dodge Neon SRT (2.4l turbo) came from the factory without a muffler. BMW M3s(E46 and up), AMG Mercs, Corvettes any sports sedan/sportscar that comes to mind.....hell, with the old Honda/Acura integra type-R(95-00), when you got into Vtec the intake tract noise alone would be north of 93db.

New car off the lot = Ticket..........but if you have a Harley motorcycle, you can run straight pipes that wake the dead with nooooooo problem at all :shrug: (Ugh....California can be stupid at times :rolleyes: )


but our newer system is if A officer gives you a ticket and you dispute it. They pull your file. - Yeah car has file with state Roads system with photos and drawing of the Emissions and exhaust. So if you make changes they know then the fine you for it.

More and more people I know now are either going full stealth valves or Just buying AMG's or HSV's or stock Modded hot rods. It's alot of pain these days.
On one hand I have to say, thats very thorough, with access to database of vehicles for compliance checks and what seems like active enforcement...esp compared to how things are run over here.....randomly checked, subjectively measured and inconsistently enforced (asian kid with spikey hair and a lowered japanese car = ticket magnet/money generator). On the other hand, that sounds pretty brutal. It seems like, stock or nothing? (with zero leeway given). Whats the rationale for the heavy handedness of the regs there?

Gavin
 
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