After taking one 16 week semester of "Intro To Tig" last fall I decided to take on making an exhaust system for my 92 Integra as my "Intro To Fabrication" project for this semester. My car didn't have an exhaust on it other that a short 90 degree downpipe. I knew this project was going to be challenging for many reasons, but figured if I have to make something and spend my own money on material, I might as well make something I want and need.

It's all made out of 304L stainless, 308L filler rod. I used 45-55 amps depending on which part I was working on. The machine I'm using is a Miller Dynasty 200, sr-20 torch, gas lens, 8 cup, 1/16 2% thoriated tungsten, and about 20cfm argon.

My turbo hangs super low as you can see in this photo of how my downpipe was before



Trying to find bends that had a tight enough radius to get turned underneath the oil pan and still have enough ground clearance just wasn't going to happen. So I had to make my own bends and figured pie cuts were the best option. I had a bit of struggle figuring out how I was going to do them until a guy in class helped make me a template in the 3d computer program. I wrapped the template around the pipe, drew the lines, and cut as needed. Worked out great.



I marked up how they need to go and then tacked them together (after sanding the edges and removing the burs)







After making sure it was all going to be in the right spot I took it back to class to weld together. Oh yeah, I forgot to mention I don't have my own welder so everything I did had to be taking to class to cut, then taken back home to test fit, then back to class to weld. A bit of a pain to do this without the car on a lift and not at the place I can weld.

I had to do very small welds here and there to keep it from warping or distorting. In the end this part alone took me a little more than 4 hours to get completely welded. I'm sure if it wasn't my first time doing this type of thing it would of been a lot faster. Even so, I'm more than happy with the way it came out.









Back purged with 10-15cfm Argon gas. Penetration isn't prefect, but it's nearly 100% everywhere


Best part, fits perfectly =]








Welds aren't perfect, but again it was my first attempt at ever messing with pie cuts or making a downpipe and I think it came out great.

After that I cut the straight pipe part and welded on the flex joint. I was using 1/16th rod at first (cause that's what we use for everything in class) and the bead was way too small. The lip on the flex joint was tall and kinda had a double lip on it. One of the instructors told me to use a 3/32 rod and try and walk the cup to get a much wider bead to cover both lips. I had never done any "walking the cup" before so it was fun to figure that out although I more like wiggled it than walked it. It didn't come up super consistent, but the bead is plenty wide.







Then I welded on the two o2 bungs




Added a little extension pipe and the other vband flange




And how the downpipe looks completely finished (**** picture). I think it's pretty good for my first ever attempt and making something other than T and lap joints and nothing had to be fixed or corrected =]



Then I took the downpipe off to wrap it to match the dumptube and charge pipes





Took the car around the corner from my house to a park to get a quick cell phone shot and to hear what the downpipe sounded like...LOUD AS ****! lol Way louder than the little 90 I had on there before



After the downpipe portion was done I went onto making the middle section

Started with the vband flange that connects to the flange on the downpipe. Made this bead a bit wider than I did on the downpipe flanges.



Hanger. I set it up to be underneath the pipe and added supports to help secure it









Bottom side



This is why I wanted the supports. This weld wasn't very big because the contact point with the pipe was small



Vband flange that will meet up with the flange on the final section that goes over the rear lca (have yet to make that last section). I made this weld a bit wider. I wanted to wiggle the cup a bit and see how it turned out. I like the way it looks





A couple 90 degree bends to get around the gas tank



And the whole middle section



Unfortunately my car is missing the hanger that would go right before the lca. Not sure why it's not there, but I'm going to weld one onto the car once I can get it to my friends shop after the whole exhaust is done. Oh and I don't have any close up photos of the welds other than the flanges. I'll get some though.

That's all I've gotten done so far. I'm going to get started on the final section in class this week which goes up and over the rear lca and then over and out of the bumper =]

I'm glad I chose a project that is challenging me and I've learned so much throughout making this. I think that shows even in looking at the first welds I did on the downpipe to the latest ones on the mid section. I'll post more photos and updates as I get the final section done

 

Nice progress! That is sometimes the biggest issue with people who are learning - you just have to get out there and try it out. Don't be afraid to mess things up, because that's how you learn best sometimes. The center hanger is overkill, but overall it is very nice for your first project. Congratulations!

 

Thanks I appreciate it. Exactly, wont know if you're capable of doing something unless you try right? Yeaah I knew it was bit much, but figured better safe than sorry I guess.

Got a bit done today. I started on the part that will go over the lca









^All that crap on the edge of the flange is just the sticky residue from the aluminum tape I used for back purging. It'll come off with some goof-off

I'm going to test fit it tomorrow and see how the next pieces need to be

 

Heres a good formula for pie cuts

Just find your clr and this will tell you what angles to cut and how many for the bend you want

http://www.homemadeturbo.com/fabrica...t-bends-78328/

 

Nice purge job/That DA is t!ts

 

you can read and study all day long. nothing is as productive as getting in and doing it. get active, make mistakes, research the mistakes and why it happens. fix it. make more mistakes, learn why. Repeat. thats my process at least

 

Nice job!

What are you planning on doing for a muffler? I also noticed you don't have a resonator.

 

I used something similar to that actually. Some little download that all I had to do what type in the angle I wanted, the clr and how many pieces I wanted and it told me what the pie cuts needed to be. Things like that are great
Thanks, and lol never heard anything call something ****
Exactly. So far I've been lucky and only had to fix one thing I screwed up on. I had to take a couple inches out in one spot on the middle section, but that was my fault for not measuring twice.
Thanks. No cat, no resonator, no muffler. Basically straight pipe all the way from the turbo back. I like the way turbo cars naturally sound without any alterations to the sound in the exhaust. That being said though if this ends up sounding like dog **** than I will add a muffler on. I'll fail emissions, but I can get around that.

I'll post some updates later tonight. I'm about to head up to the school and add some pieces on. I was going to do it in class yesterday, but unfortunately FedEx didn't show up with my 90 and 45 bends until after I had already left

 

Got a bit more done the other night. The parts that needed to be added to get up and over the rear control arm are welded on now.

Looks weird cause it's not sitting in the position it will on the car





Here is how it sits when it's on the car. The two piecuts at the end of the pipe were needed to allow the next pipe to be perfectly straight and parallel with the ground like the sway bar is. I've got the hanger made as well, just need to weld that on when I go into class on Monday.







Now that I know all of that will work and clear the sway bar and everything I moved on and started designing the last piece. I've been using 3" cardboard mailing tube this whole time when designing each piece. Stuff works out great for helping me get things right before cutting any actual metal. Anyway I got it pretty much how I want it. It's at a slight angle, but nothing crazy. Coming straight out looked stupid and although it looks like it sticks out a lot it's actually flush with the bumper which you can see in the last picture. I think it's gonna look sweet when it's done. Hopefully it wont burn my bumper or get black **** all over it, but I'll see. I don't want to do a turn down at the end even though that would help avoid those potential problems because I those look like limp dicks lol. Just looks weird











I should be able to finish it up next week =] Fingers crossed cause I've only got 4 more classes including next week and then after that...I have no welder

 

Nice!

A little angle is always nice.

 

I personally would have made the top longer (flush with bumper) and back-cut the bottom section for an angled exit. The bottom sticking out further is what we call "rain collectors". I am not one for angled exhaust myself, but if you like it then that's what matters. Also, where I am from the saying usually goes "That **** is ****!".

Having no resonators will get VERY annoying at highway speeds with a straight through 3" exhaust. I had a CRX that I tried just a fart can on with full 3" and it was deafening... the older cars just don't have the sound deading the newer ones do. Even just a muffler won't be enough, resonators perform a specific job hence their nickname.

 

good ****

 

Thanks. I think so too
You know that's a really good point. I never even thought about the rain thing. I don't ever drive the car in the rain, and it's garage kept as well. The only time it really sees water is when I wash it. I could always put a lid or cap from something over it when I wash it to keep water out. I can also cut it later if I feel it's becoming a problem. I'd go cut a piece to test, but I'm out of time today.

As for the resonator, I know it'll be loud. I was running that tiny little 90 degree downpipe for months. I know how that bitch droned on the highway. I had a full stainless rsr exmag before and I loooved how nice that sounded. Unfortunately was too small for the turbo. I'm hoping this wont be too bad since it's way behind me, but guess I'll find out. The car isn't my daily either so dealing with it once a week to and from the meet isn't bad. Again though, I will find out
Thanks

Oh, OneBadTurboCRV. This is how it sounded with the little 90 degree donwpipe. Thing was crazy loud




Oh and one showing the whole setup when I first got it done


I'll be back in class tomorrow so I'll post more updates either tomorrow night or Tuesday

 

Looks good but i would cut the last part at the bumper at like 30 degrees from the tip i think itll look a lot better

 

What ems are you on? That 2 step is cutting fuel. You need to retard then cut igniton.

Itll build boost and sound a lot better


Heres mine.

 

Looks great!

 

Sounds nasty man. Turbo spool sounds great. In that video my car was still on Crome. I'm on an s300 v3 now, but not tuned. Going to get a tune after all this exhaust stuff is done
Thanks.

I welded the last section together today. Didn't get any pictures, but I did get a quick sound clip of it on the car though.


Last thing is too weld on the last hanger tomorrow and it'll be done =]

 

So today I welded on the last hanger and had some fun with a blow torch and make a ricer mod...

I decided to see what it would look like if I burnt the tip and I think it looks sweeeet!





Unfortunately though everyone said to add clear coat or else it will eventually wear off. I listened, added some high temp clear...and watched the intense colors fade away to a dull, boring, blah look =[




The clear coat basically removed all the intense blues and left just the dull purple. Adding the clear coat might help it last longer, but it makes the colors way too sedated. I'll wait and see what it looks like in the sun tomorrow, but I have a feeling I will be redoing it...the burnt tip that is, not the exhaust. That came out great. Sits exactly how I wanted it

 

Thanks

Sooo it's finally finished. I ended up redoing the burnt tip and got some blue back in it. It still didn't come out as intense, but I like it cause it's just enough without being overkill.

Here are the last of the photos of it

Hangers




How the last section sits





And how it looks on the car









Went and drove the car for the first time with the new exhaust on and I think it sounds amazing. Sounds way better than I imagined it would. Super deep tone, no rasp, nice and quiet when I'm cruising around. I'm surprised it's as quiet as it is with no cat, resonator or muffler. Couldn't be happier with how it turned out. Can't wait till the car is tuned and I can hear it in boost

 

Fantastic job for your first exhaust.

I didn't hear anyone mention it - but you'll want to replace that flex section with a lined flex section.
Years ago, I had those cheaper style flex sections collapse on me. The ones with the braid exposed on the inside are a no-no for turbo cars.

This illustrates well what I'm speaking of:

http://i67.photobucket.com/albums/h2...s/IMG_2428.jpg

 

Thanks. Someone actually did mention that to me right after I put that piece on. I looked up a bunch of photos of that happening and it makes me nervous. I know it WILL happen sooner or later. I will replace that flex joint at some point, just don't know when. I wont have access to a welder come the 13th when the semester ends, so I'll have to wait till the fall to fix it. If it happens before then I'll figure something out.

Thanks for the heads up.

 

the flex needs to be replaced. also, the wrap should come off. it prematurely fatigues welds on a daily driven car. wrap is for race cars, not street cars. if controlling heat is a concern, you'd be better off with a properly made heat shield. wrap will overheat the material to the point of failure because it does not allow it to shed heat properly. this is fine for a race car that doesn't run for long stretches at a time, but on a street car that is seeing prolonged and repeated heat cycles it is a no-no.

aaron

 

^^^ceramic coat or Jet Hott instead