Ford Forums banner
1 - 20 of 20 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter · #1 ·
im removing my catalytic converter mainly for better fuel efficiency, but will my exuast be louder and will i get a few more horses.

thanks
 

·
Super Moderator
Joined
·
11,173 Posts
The cats don't really make much difference. The way they are made the exhaust flows very easily with a VERY slight restriction. The check engine light will be lit too.
 

·
Pantherholic
Joined
·
375 Posts
i would be cautious about removing the cats if you have inspections in your state. i would try to find duals for your car from a police car... that will improve it some on your mpg and also power
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #4 ·
i see, but ill do it anywayz becuase where i live, there not required. and i already have duals

thanks :)
 

·
Registered
Joined
·
16 Posts
I am not sure which yr car you have, but removing the cats will increase sound... and h.p., maybe. If it is has a carb on it, it will work. If your fuel injected, you have a pesky computer and oxygen sensors. They have what is called "upstream" and "downstream" oxygen sensors. Basically means one before the cat (upstream), and one after the cat (downstream). If the "downstream" oxygen sensor monitors no changes from the "upstream" oxygen sensor, the computer MAY signal a 'check engine' light and RETARD engine performance. So, you'll get a bit more sound, however, the performance may suffer, that is if you do have that arrangement of oxygen sensors....???
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #7 ·
i have a 2003 crown vic.

now im having second thoughts 72mgm scared me :p

garage is going to open in a few hours, its 5a.m now, ill ask him if hes sure about the whole thing, and if it goes wrong ill just put it back

thanks everyone =)
 

·
Registered
Joined
·
16 Posts
A 2003.. ok, you should have 4 cats on that car.. I cant recall, but if the o2 sensors are surrounding the 1st cat on each side (driver and passenger), then you should be able to remove the second cat, and that should help a bit...
 

·
Super Moderator
Joined
·
11,173 Posts
The O2 sensors are behind the second cat too. The O2 sensors on the older Crown Vics were between the two cats.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #10 ·
thanks gentlemen, ill keep that in mind, very helpful, im leaving now, ill let you know what happens.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #11 ·
well i just dropped my car off, its THEE best place, its alos the most expensive, lol

there the only exuast place that say there pretty sure actually ''80%'' that the light wont come on, and there people are skilled, so im hoping that everything goes well, there going to remove all 4 of them, and put a 6foot pipe for both, and re-attach the sensors, it will be ready tommorow, cant wait!
 

·
Registered
Joined
·
111 Posts
I still don't understand the reasoning behind removing the cats. The gain in fuel economy will be so negligible it will take you years and tens of thousands of miles to recoup what you're spending on this. Why not invest in low rolling resistance tires, a marauder/p71 intake, or some new iridium plugs. Or if you're set on exhaust work have your guy put in an x-pipe to get a better sound without messing with the emission system.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #16 ·
im from bahrain

i just took my car back, and thank GOD the check engine light didnt come on, there is no increase in power, maybe a decrease but i dont mind, didnt drive it long enough to check the fuel.

on the downside, the sound sucks, its sounds like crappy honda with all that rattling + my display that tells me how many miles i can go before im emty and the mpg has gone bonkers

the garage said the sound sux becuase of all the pressure going to the back 2 mufflers, since i relieved alot from removing the 4 cats, they say the only way for it to sound alright, is to put to more mufflers, one on each side, and really dont want to do that, its gonna cost alot, is there ANYTHING i can do guyz, i really need your help on this one, i was expecting more of a v8 sound, not a 4cylinder honda (no offence to honda oweners )

thanks guyz
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #17 ·
i drove my car for about an hour, and if im not mistaken, its drinking more fuel:BW:

im such an idiot :angry:

the sound is also beginning to annoy me
 

·
Registered
Joined
·
16 Posts
This is a E.F.I. machine for sure.. designed to be squirrel friendly... Don't worry, you can fix it, but will cost you a few more $... If you have the cats still, what I recommend is to put 1 if not both back, and make sure the o2 sensors are on either side of the cat on both passenger and driver side. If you dont have them, magnaflow has direct replacements:

http://www.magnaflow.com/02catalytic_converters/02product/shopdisplayproducts.asp

Then for sound, I am personally partial to Flowmaster. I am running 2 40 Series Delta Flow 2 Chamber Mufflers... part # 842441.

Flowmaster 40 Series Delta Flow -Two Chamber Mufflers

These are 2.25in. in and out. Our cars come with 2in. pipes.. So, I ran 2.25in piping back from the cats, over the axel, then the last 12in. of pipe to bumper, I increased to a 3in. pipe to give it a bit more echo / hollow sound that the Flowmasters are known for.. Better Throttle response, aggressive sound outside, and LOW interior resonance.. Thats why you go with the "Delta series". The original 40 Series WILL echo and give resonance in the car.. and quite frankly, drive you madd after about 20 miles on a trip anywhere, or maybe sooner... Then again.. some may like that :MmM:
 

·
Registered
Joined
·
1 Posts
I am not sure which yr car you have, but removing the cats will increase sound... and h.p., maybe. If it is has a carb on it, it will work. If your fuel injected, you have a pesky computer and oxygen sensors. They have what is called "upstream" and "downstream" oxygen sensors. Basically means one before the cat (upstream), and one after the cat (downstream). If the "downstream" oxygen sensor monitors no changes from the "upstream" oxygen sensor, the computer MAY signal a 'check engine' light and RETARD engine performance. So, you'll get a bit more sound, however, the performance may suffer, that is if you do have that arrangement of oxygen sensors....???
I am not sure which yr car you have, but removing the cats will increase sound... and h.p., maybe. If it is has a carb on it, it will work. If your fuel injected, you have a pesky computer and oxygen sensors. They have what is called "upstream" and "downstream" oxygen sensors. Basically means one before the cat (upstream), and one after the cat (downstream). If the "downstream" oxygen sensor monitors no changes from the "upstream" oxygen sensor, the computer MAY signal a 'check engine' light and RETARD engine performance. So, you'll get a bit more sound, however, the performance may suffer, that is if you do have that arrangement of oxygen sensors....???
Well I did a cat delete just now on my 06 took me two weeks or so maybe a month where I cut my cats and ran qit nothing I advise u don't do that it's ungodly loud I went back put straight pipes in place of cats left upstream on sensors cut the downstream off my engine lights on so r brake and abs bs so idc bout that but when I did cut it I gained more horse power it was crazy I got the pipes on it I restricted some power but I run stock what ever else in back on all this and till I get down on my car it quite now then I get down on it racks off like a v8 truck does its still string tho don't get me wrong I cut back a Lil bit so idk another guy told me I'd burn a hole in my piston but I looked on line from removing the downstream I haven't heard or seen any of that so idk but so far so good besides a check engine light when I bought car it had stopped up cats I almost thought it was a transmission Goin bad it jerk cutting in and out Goin down bout 55 mph
 

·
Super Moderator
Joined
·
1,902 Posts
Well I did a cat delete just now on my 06 took me two weeks or so maybe a month where I cut my cats and ran qit nothing I advise u don't do that it's ungodly loud I went back put straight pipes in place of cats left upstream on sensors cut the downstream off my engine lights on so r brake and abs bs so idc bout that but when I did cut it I gained more horse power it was crazy I got the pipes on it I restricted some power but I run stock what ever else in back on all this and till I get down on my car it quite now then I get down on it racks off like a v8 truck does its still string tho don't get me wrong I cut back a Lil bit so idk another guy told me I'd burn a hole in my piston but I looked on line from removing the downstream I haven't heard or seen any of that so idk but so far so good besides a check engine light when I bought car it had stopped up cats I almost thought it was a transmission Goin bad it jerk cutting in and out Goin down bout 55 mph
???
 
1 - 20 of 20 Posts
Top