Needs some work- exhuast question

[borjawil]

Hey everyone just picked up a 88' bronco 2. Its a project and i've always found these sites to be helpful.

The truck basically needs a new exhaust and the brakes need to be looked over. Will be picking up a manual here shortly.

Any advice on replacing the exhaust?

Im mechanically inclined and have done electrical, brakes, engine work on bikes, only changed the oil on cars for the most part.

[RClem]

Welcome to the forum.
Unless you have the equipment to do the exhaust, I'd go to an exhaust shop.
How much of the exhaust needs to be replaced? The cats are what is going to be expensive, but you need to keep them, and don't go overboard on the pipe size.
If you keep it the same size as what is between the cats it will work just fine. Oversize pipe will cause a loss in back pressure, on a V6 this isn't good. Especially a 2.9, which is what came stock in you 88.

Ray

[borjawil]

I have the equipment, nto sure how much needs to be replaced, will check further into it. What are the "Cats", and why must i keep them. thanks.

[kolton]

flowmaster super 40
lmctruck.com usually has a decent price on cat's. and they have
sounds good even out of a tiny pipe. i think the stock pipe size is 2 1/4? not surealot of parts that might interest you. order the free catalog.

mine comes out of the headers for 5 in. then goes into the modified flowmaster and then goes into a dump under the passenger seat. probably not the best setup out there, but its all i had at the time and it works.

kolton

[RClem]

Quote[What are the "Cats", and why must i keep them. thanks.]Quote
Catalytic converter: to start with "federal law".
Like Kolten said LMC, follow the link: http://www.lmctruck.com/icatalog/fr/full.aspx?Page=103
You can get a system called "cat back", it moves the cats back further, I have never used or even seen them, but those who have them say they are "the cat meow", pun intended.

Ray

[joeyy]

I am always having trouble with my exhaust. from the muffler back it completely rusted out so I just cut it off from there. so it was just the cat and the muffler sticking off the headers. But everytime I went mudding, both would always fall off. So finally I rebuilt the system and bought a new muffler(glass pack) and put the cat on behind it but it was facing the wrong way (1 didnt know it had to be a certain way and 2 the forward filter shattered but a chunk was still in there and i didnt want it to mess up the other filter) then I was driving up the free way and the other filter shattered, so I took off the cat becuase I thought it would help, cuz the truck was running really rough. Once it was off I found out that it was complelety destroyed. So now I dont have the cat on it or have another cat to put on it. My rig needs some exhaust work but I'm flat broke. should I put the empty cat box back on to help with back pressure? My gas mileage has really suffered too.

[borjawil]

Just a few questions so i can determine what is bad on my exhuast. Havent looked at it to close yet so i was wondering how to tell if the catalytic converter is bad. the muffler is in good shape the pipe from the muffler out the back is rusted through.

[ranger5.0]

I believe stock exhaust is 1 7/8's. I did 2 1/4 rom the Y pipe back on mine with a flowmaster style muffler. The muffler had baffles for back pressure and the flow was excellent with a good sound. I wouldn't try duals. they sound bad and don't give the engine equal pressure to scavage the exhuast out of the engine. Glass packs are illegal at anyplace that requires a spark arrestor. plus they burn out and pretty much are straight pipes. useless. Typically a stock muffler will rust out from the inside out. Stick your hand out by the tailpipe while it is running, see if debris hits your hand and that will tell.

[tekatlarge]

Quote[What are the "Cats", and why must i keep them. thanks.]Quote
You can get a system called "cat back", it moves the cats back further, I have never used or even seen them, but those who have them say they are "the cat meow", pun intended.

Ray

Hey Ray,
Cat Back actually means from the Catalytic Converter on Back. It is how aftermarket suppliers get away with messing with the exhaust on a automobile and assure that they are not violating any federal law.

It is a violation of Federal Law to modify tamper with or remove any part of the emission system of a street driven automobile. (read catalytic converters) Also as an individual you are forbidden to tamper with any part of the emissions system. Suppliers make kits that you can install as long as the emissions are not tampered with and because the Catalytic Converter must remain they sell you a muffler some clamps and some pipe all pre-bent ready for you to install.
When you hear someone say they got a cat back exhaust it means they replaced the exhaust from the Catalytic converters back. This exhaust usually takes a single pipe exhaust and turns it into two tailpipes.

This notion of moving the Catalytic Converters back is just pure nonsense!
Moving the Catalytic Converters back makes no sense to me at all.

No offense intended.
Just an
FYI

[RClem]

tekatlarge:
Thank you, now I know why I have never seen or used one, actually I have, but it wasn't a kit, had an exhaust shop install new pipe and mufflers on both of my RBV's.
I have known a couple people who removed their cats and had all kinds of problems until they replaced them, these were electro/mechanical problems, not law.
When they started putting cats on, way back when, Car & Driver used a Camaro of that year with a 350 to do a test of what cats did to performance, I don't remember all the particulars, but in the end the Camaro actually ran better with than without. It was a good test and all the data was there, with and without cats, dyno, 1/4 mile and economy, they all suffered a little by the removal of the cats.
If I could find the article i would post it some where for all car owners to read, even tho it is an old article.
Absolutely no offense taken.

Ray

[tekatlarge]

You are right on there Ray

The cats of today actually are part of the "Whole System). Fuel injection is much more efficient way to control fuel and spark than a carburetor is.

[oneway]

jcwhitney.com has cats for $181 - is that expensive?

i think i have an exhaust issue as well, as the truck idles fine, but gets loud when you get on the gas...then is quiet as you get going faster. Accleration seems a bit sluggish - she'll still jerk you back if u blip the gas, but it jus seems like i really have to step on the pedal to get some accel.

are these trucks '90 Bii v6 2,9l 4x4 automatic naturally loud?