Exhaust project

[Lynkx]

Hello.

I have a 1987 5.0, me and a freind with a nice arc welder will be doing some exhaust for this.

We are planning side exit exhaust.

Now questions, i don't know much about exhaust.

Will i need cats for backpressure? (Its legal to have them taken off here)

Will straight pipes with only resonators be too obnoxious for day driving?
Whats the size i should use for a 100% stock engine? 2.5 inch?

Also, will the computer have problems with this, and will the oxygen sensors spaz?

Thank you for your help.

The project is for fun, gears(4.10 or 3.73) and exhaust, cheapest way to go for a fast little sleeper, 10 holes included!!!!

 

[90mustangGT]

No, backpressure is not needed in any setup. The reason for smaller pipes is to keep velosity. Minimum backpressure is the key. No you don't need the cats. The only thing you need to keep is the oxygen sensors because they are nessesarry for the computer to properly meter the fuel:air ratio. If you delete the it will run rich and like crap. The exaust setup will not effect the computer. I would suggest keeping some kind or balance tube such as a H or X pipe, this has a lot to do with both sound and power.

 

[sleeper89]

FWIW i'm not sure an arc welder is going to be the best thing. you'd probably want a mig for the thin wall exhaust tubing.

-steve

 

[Lynkx]

Yes, a custom made H pipe will be made for it.

I am keeping the sensors, i just wanted to make sure of the positioning.

Shorty headers might be part of it(ill just be buying those) but im not sure if stock or that will be better?

I don't want an obnoxious car, i want somthing that will sound mean, but not like im trying to scare the bloody 'Kiss Me''Kiss Me''Kiss Me''Kiss Me' out of pedestrians, or kill birds with the soundwaves.

 

[stang22]

FWIW i'm not sure an arc welder is going to be the best thing. you'd probably want a mig for the thin wall exhaust tubing.

-steve

My thoughts exactly. Seems line an arc welder would burn a hole right through those thin exhaust pipes.

Tim

 

[Timmey9]

Let us know how it goes. My friend and i are going to be making a custom exhaust for me this spring. He knows how to do all the welding and is either using a MIG or TIG welder depending what he can get his hands on at the time. I was thinking of making my own X-pipe but then we got bored and made plans to make a prochamber type of exhaust. Just wish we could get some better dimensions of one.

 

[T.J. 87-GT]

The best way to do this would be with a TIG. However a MIG can do this well but you have to grind back and check for holes. Also I have done many turbo DP and such and I check my TIG welds with custom made caps on the end of the pipe and have a fitting on one of the caps and run compressed air in there. Here is a pic of a stainless section of pipe that has been TIG welded to a regular section of exh. pipe by using 309 filler rod. Note I did not use a lot of filler rod here cause the fitment was nice and tight. The pipe in the backround is all stainless.

T.J.

 

[larrendeuce]

Hey nice welds

 

[siege]

hmm..those welds are nice indeed. you should see the work the kid at MIDAS did on my mufflers...HORRIBLE! not even close to a stack of dimes or nickles or whatever it is. just piles on piles of weld and some pieces of wire hangin off. have a feeling I coulda done a better job myself and I can't weld

 

[Lynkx]

Well, hes the one with the knowlage, hes done exhaust work alot, so im probably thinking of a TIG and not an arc welder.

[EDIT: he has a MIG]

 

[Lynkx]

Ok, well im starting it next tuesday, if anyone has any concerns ie: sensor location, ect. please post.

 

[Lynkx]

Hi guys, just out of curiousity, my freind recommended flex pipe to be used...

My question to you is, do i need it? All i notice it doing is letting the exhaust hang lower.

Thanks for the info.