I'm new at this forum thing so please excuse any ignorance. I have read some of the threads about a Cat exhaust system. I have a 2000 F-350 5.4L. I would like to put a dual exhaust system on my truck but have been told it would mess up the computer. Please explain the Cat system, and can one of those Diablo chips be programed to accomidate this type of exhaust system for my truck. Finally the big question, Does any one know how much all of this will cost, I assume much better performance.
Thanks, I hope my questions are not to long.
MikeMcq

 

if your talking about a cat back system it means replacing everything from the catalytic converters[cats] out the back- this includes free flowing pipes ,mufflers and catalytic converters to reduce backpressure which increases power and economy.The main problem with the computer is to get the o2 sensors back where they should be so the computer does not keep throwing error codes! The cost of a set of real duals can be anywhere from 500 to a grand-it depends alot whether you go with steel or stainless-computer chip will run about 250 but be warned you might have to run premium after you change chip!

 

Are you talking about a true dual system (as in each bank exits outs its own respective tailpipe), or one of those systems that is single from the manifolds to the catalytic convertor, then branches out into two smaller pipes? This subject is talked about all the time in the big bronco forum. First, true duals are expensive, and if you have visual inspections in your area, you might run the risk of being hassled (not sure about the whole country, but up here in MA, if it isnt stock, youre asking for a headache) Second..most single 3" performance cat back systems flow as well, or better than true duals (unless youre running dual 2.5-3" pipes with an H). Any reason for wanting to run duals? I had them on a 76 F250 and I loved them (i had dynomax race magnums on, so it helped when the cops would drive by, and only hear it after they had passed me). Also, positioning of the oxygen sensors is critical for the engine management system. I just bought the Bassani Street Thunder system for my 96 Bronco, its going on in the spring. Its a set of high flow ceramic headers, high floy Y pipe (flows MUCH more than stock), and a 3" single catback(all stainless steel). The whole system probably cost me $1100. It retains all factory emissions locations, and is a simple bolt on unit. If youre deadset on duals, good luck. I do not believe anyone manufactures a true dual system except for a local exhaust shop or something fabricating one up for you.

Rich

 

I was going to respond (busy weekend) but it looks like you're question has been answered perfectly. The only thing I have to add is that the part of the oxygen sensors is not only right, but critical, especially if you want the truck to get the right A/F ratio and also not set off the check engine light.

 

Thanks guys, I think starting with replacing the Cat to a high flow and putting on a ??? (Flow Master) muffler will probably be the route I take. Where can I get a High flow Cat? Thanks for all the knowledge.
Mike

 

Glad to help-I like magnaflow better than flowmaster-alittle cheaper and not quite as loud and just as good!If I were you I would just replace the muffler and see what it does-it would be alot cheaper and you can always go back and do the cats later if you want-I think you will be suprised with just the muffler[cost about 120 installed]

 

Thanks for all the advise, I am scheduled to have a Magnaflow muffler with dual output installed on my truck next week. Will this make much difference by itself or do I need to also install a high output Cat? (I plan on installing the cat latter) What is a average price for a high output Cat?

Thanks:
Mike

 

I would wait on the cat and see if what your doing makes you happy-if it does -great if you want more do the cats-free flowing cat anywhere from 200-350 depends if you want stainless steel or just steel

 

WOW, Thats what it will cost to have my new exhaust system installed. Thanks for the advice.

 

Yeah I know thats why I opted for the cheaper route-all the muffler guys I talked to told me perfomance wise that comparing a true set of duals to what you are doing that the performance and economy differance is minimal if any at all! I figured the money looks better in my pocket than theirs!

 

Just checked the prices on magnaflow stainless steel free flowing cats-100 bucks a piece-hope I didnt give you a heart attack with the other cat price quote-lol-oops-sorry about that!

 

$100 is not bad at all, Will it make much difference since I'm already putting a magnaflow? Thanks for all the help. This beats a muffler shop trying to give you advice and sell there product. Next question, will this exhaust work change which diablo chip I buy? In other words will I need to buy a customized chip?

Thanks'
Mike

 

As long as your current cat is in good shape I think the benefit would be minimal.If I remember right the diablo chip can be programmed in about any config you want but as far as having a "special" config because of the exhaust-no. I do know that you can get it where you can keep using regular gas though because these highperformance chips basically advance timing,adjust air flow and lean out fuel mixture[standard chip runs a little rich to compinsate for poor gas so it wont screw up your cat]the chip that lets you run on regular wont lean out fuel mixture[to me this is a better idea so you wont take a chance of screwing up your cat!]To me the best idea is to go slow and do a little at a time because if you shotgun it[do it all at one time] and the perfomance and economy get worse you wont know where the problem is!
Good Luck
Mark [Slipdaddy]

 

A chip that runs 87 octane (such as JET) does not do anything for performance. It'll only tune at wide open throttle and do tranny mods. Anything you feel below WOT is just the program making the gas pedal more sensitive. The part you said about leaning the mixture isn't fully true because it doesn't factor in a critical factor about premium fuel. The cats get hot when a mixture is too lean. Premium fuel runs cooler therefore you can lean the mixture a little without overheating the cat.

 

yes that is true as long as you use premium but if you want to stay with regular its not advisable to lean it out!If you read the lit on the diablo chip which is what he was talking about they will adjust timing ,a/f and shift points but wont lean it out on their 86 octane chip