(posted in general also)...
to custom build exhaust from cat back? i have the need to be different and have a few ideas, just seeing if anyone has done this themselves.

 

I’m pretty sure there is a vendor that sells parts to make a custom exhaust system. I hope someone who knows will chime in. But with so many nice systems out there, why not put your talents to something else? Like maybe a DIY catch can. I want one of those, but no way in he!! am I going to pay some $200 for one. Good luck with the project though, if you decide to do it. Oh, and post pics!


Clayton from Las Vegas

 

I'm very interested in this, but couldn't find much information on it. Does anybody have any links to a write up on this forum for this? Or perhaps links to sites where i can order the materials for this?

Would it be insane to just have straight pipes with NO resonators or mufflers? Just pipes from the cats to the tips. ( I mean is it to loud or illegal?)

What diameter pipe should i use, what are the stock pipe diameters on the stock axelback system?

I'm just not seeing the sense in spending $600-$700 on B&B Bullets (which is the only ones i even like...) when for under $200 my friend and I can weld some pipe together...

 

You might be interisted in this. Stainless works 3" tailpipes. Only a few hundred bucks. It's a good starting point and 3" mandrel bends and pieces will cost you just as much.

 

Yes! This is good! You can just bolt those right on eh? If i wanted different (quad) tips i would have to cut them back a bit, then weld on a different tip? (Basically just a Y pipe tip, for looks...) Or are they the right length already so i can just put a tip on w/o having them stick out 6"... lol

Thanks again!
-Dan

 

without the aide of software and a sound wave technology degree, anything you do will be speculation as to the sound note, noise canceling capabilities, actual flow rate, and back pressure... this is 2006 not 1960... every exhaust manufacturer uses sound wave engineering technology to bend and shape the sound, not just for frequency response, but for performance and flow...

 

Thank you Evil-Twin, I'm glad you reminded me what year it is... and to think... all those checks i wrote... wrong...

My friend however, does have a car from the generation you mentioned... It's a 1969 Chevelle w/ a 396 headers and straight pipes. From the end of the headers to the Exhaust tip was basically pipes ordered by his mechanic friend, and put into place. This car BTW sounds very good, but i guess ~500hp built engine helps that too... hehe I'm sure with an engineered exhaust system it would gain 10hp maybe...(?? lol... not worth it...)

Why don't we just take the stock axle back off, and let the air come out 2ft sooner? (direct the tips downward...) What affect would that have? It wouldn't be much different (RWHP wise) than an extra 2ft of straight pipe... My point is, I'm not trying to mess with thermal dynamics, flow dynamics, audio dynamics, or whatever else is involved on the exhaust. I simply like the sound of straight pipes, and don't like the cost of B&B Bullets so much...

All the reading ive done pretty much concludes that the axle back components aren't really going to affect your performance a whole lot, and is mostly personal preference on the sound. (Especially if you're not FI, no headers, and still have factory Cats)

So i'd like to chop the muffler, toss on 2ft of pipe to bring the tips all the way to the back, and call it a day... I was hoping to find someone else who has done the same.

TurboC5 i can't seem to find what you posted a picture of... do you happen to have a link?

 

But dyno numbers have proven that unless you have a very serious engine (600 H.P. or so) the muffler section doesent give you any more than 3h.p. or so. Not in my opinion really worth the R&D time for the power. Sound yes, but not power. Its trial and error, but thats what makes fabrication fun. Anyone can simply bolt on parts but building your own parts that preform gives people more sastifaction.

 

Sorry it was random tech, not stainless works. I couldn't find it eather before but I just found it . http://dezod.com/cat_c5_exhaust.cfm

 

that is why i was questioning just using resonators, i'm leaning on the borla or glh muffler, then i'll custom bend the s shaped tailpipes and tips. i figured the technology is in the muffler, the tail pipes can be cloned by a good pipe guy. it would be nice to find a used set up somewhere for a reasonable price.

 

So if i take the factory overaxle system off, i can just bolt that straight to the car, and if i wanted to, i'd be done!?

 

i don't think so, check the site, that is 3" i don't think factory x is 3" but i'm not sure.

 

Apparently i'm a little confused on the exhaust portions of my car... ive only had it a couple weeks, so i'm going to guess on this, correct me please.

The exhaust is basically in 3 sections.
1) The exhaust manifold/headers
2) The Cats, X pipe, and extension to Axle
3) The Axleback system including muffler and tips...

I'm only looking to replace the 3rd section, leaving the cats, x pipe etc all intact...

So the pipes on that site are from the Cats and X pipe to the Axle, and no further?

 

i'm not 100% sure probably cat back, i was referencing the notes on the link. by the way check this out...thanks to mvett97...
Wanna hear loud? This is Borla straight pipes and magna flow x pipe with no cats.http://media.putfile.com/C5-with-no-...straight-pipes

 

http://media.putfile.com/C5-with-no-...straight-pipes

Cpy/Paste doesn't works so great with "..." in the hyperlink... lol

Yeah, i'm following both threads too, usefull stuff.

 

its getting late and i can't think straight. i'm by far no expert and i can't even picture the stock exhaust layout right now. but if your looking for an inexpensive way to go straight pipe, i would unbolt the stock exhaust and save. then go to salvage and buy a used one, some members will even give them away, and cut those just before the muffler. then weld straight tail pipes back. i don't know how it would look, but it wolud be cheap. i think it can be done nicely by an experienced exhaust guy though, at least if it comes out horrible, you have your stock to bolt back on. i don;t mind spending the money i just want to be a little different. that's why i'm gonna used polished stainless. i'm in no hurry either.

 

So i'm probably going to try and do this soon. My plan is:

Cut off muffler, then remove over-axel portion of factory exhaust, w/o having to jack up my car 3ft...

Weld tip to section of straight pipe
Tip: http://www.autoanything.com/exhausts...A2437A0A0.aspx
Pipe: http://www.stainlessworks.net/cart/p...oducts_id=1265

Then put pipe and tip in place and measure how much of the straigh pipe to cut off.

Cut the straight pipe to length and weld it to the over axel portion of the factory exhaust.

Then install the system, and mark the pipe where i need to mount a tab. Then remove system, weld tab, and connect tab to the car for support, as shown in this pic. (Someone elses fabricated exhaust)
http://www.iammoon.com/images/vette/...rch_2006_3.jpg

Hopefully, i'll have a setup similar to the one above. I'd like to coat it so it doesn't rust, and i'd like to take more pictures of the install and whatnot then post them. I'll keep you up to date...


-Dan

Please let me know if my pipe diameter is wrong... and what the factory pipe diameter is... thanks.

 

I hand fab'd a system from scratch. We started with 3" flanges, 3" U-bends, 3" XR1 Mufflers and 3" tips. Constructed a Jig with a platform to hold the tips, cut and fit each piece, tack welded, once the whole system was done, we checked fitment. Fit was perfect. Ran the beads and sandblasted/painted. Sounds insane, I have never heard a 346 sound quite like this.
Phil

 

Thats pretty much what I wanted to do. How loud was it under cruse? How loud will the cops think it is under cruse with off road lg pro's I don't want to get pulled over every day. The B&B bullets arn't that loud, I could get by with those but I want 3" tubing, even if it's no benifet to HP. I wan't that 3" sound.

 

Wait Cops? Uh... there isn't anything about illegal going straight pipes is there? I mean, I don't have headers, and I still have my factory Cats, so cutting off the muffler isn't considered Tampering with Emissions is it?

BTW, I live in a county that has NO emissions Checks, however tampering with Emission components that are 'functional' is still considered illegal.

Also, I don't think there is any volume ordinence as far as exhaust goes is there? Harleys are HELLA loud, and the audio systems on darn near every import is usually crazy loud too, I can't imagine this being too loud. Has anyone w/ straight pipes had problems before?

(Thurston County, WA)