Thinking of removing the CAT - any future problems?
#46
04-28-2008, 05:18 PM
Not comparing performace by any means, it just sounds like a tached out viper when the truck in under load.
Yes my truck is a crew cab 4x4, with the off road package and the STOCK dry weight is 10,640 also shown on the title and the door sticker and verified by my personal scales I use to balance my race car since I couldn't belive it for myself.
Yes my truck is a crew cab 4x4, with the off road package and the STOCK dry weight is 10,640 also shown on the title and the door sticker and verified by my personal scales I use to balance my race car since I couldn't belive it for myself.
#47
04-28-2008, 06:08 PM
Completely incorrect. I removed mine and replaced with a length of 3" pipe. Here's my experience with it after 10,000k
1. Ford pre-programs a rich condition into the computer to help the converter retain its efficiency, so after I removed it I noticed a very minute amount of black smoke from the tail pipe. Corrected it with leaning the system out a little resulting in some power gain.
2. LOUD LOUD LOUD! The converter has honey-comb catalyst in it (I'm sure you know already), It does have great muffling capability but it also created backpressure. I have a flowmaster 3" Cat-back and it's a bit loud but doesn't sound bad by any means. Similar to a viper at WOT.
3. Was able to advance the ignition timing 3 deg more than what I had it before. Any pinging you might have will most likely be gone since the engine can breathe better.
4. I noticed a good amount of a fuel mileage increase (2-3) MPG.
5. Really easy to do, cut the pipe as close to the joint at which the cat is welded, separate the non-welded joint at the rear of the converter and replace with 2 18"x3" sections of pipe from autozone.
6. You have to read through your states DMV regulations for inspection. I noticed someone stated PA inspections as I am living in PA currently, PA doesn't require emission inspection in vehicles over 9000 lbs. My truck weighs in at 10,600 so I was exempt. The inspection criteria for the required "safety inspection" includes the "Exhaust inspection for leaks" step. Inspectors are not required to inspect for emissions equipment and cannot require you to repair the vehicle for a removed catalytic converter as this inspection is for general safety and not emissions/safety as most highway vehicles are.
7.YES it does make a power gain, significant one too. a plugged cat is definately a restriction but even the cat itself is a restriction. Throttle response is affected along with mid-range torque and a mpg gain also.
1. Ford pre-programs a rich condition into the computer to help the converter retain its efficiency, so after I removed it I noticed a very minute amount of black smoke from the tail pipe. Corrected it with leaning the system out a little resulting in some power gain.
2. LOUD LOUD LOUD! The converter has honey-comb catalyst in it (I'm sure you know already), It does have great muffling capability but it also created backpressure. I have a flowmaster 3" Cat-back and it's a bit loud but doesn't sound bad by any means. Similar to a viper at WOT.
3. Was able to advance the ignition timing 3 deg more than what I had it before. Any pinging you might have will most likely be gone since the engine can breathe better.
4. I noticed a good amount of a fuel mileage increase (2-3) MPG.
5. Really easy to do, cut the pipe as close to the joint at which the cat is welded, separate the non-welded joint at the rear of the converter and replace with 2 18"x3" sections of pipe from autozone.
6. You have to read through your states DMV regulations for inspection. I noticed someone stated PA inspections as I am living in PA currently, PA doesn't require emission inspection in vehicles over 9000 lbs. My truck weighs in at 10,600 so I was exempt. The inspection criteria for the required "safety inspection" includes the "Exhaust inspection for leaks" step. Inspectors are not required to inspect for emissions equipment and cannot require you to repair the vehicle for a removed catalytic converter as this inspection is for general safety and not emissions/safety as most highway vehicles are.
7.YES it does make a power gain, significant one too. a plugged cat is definately a restriction but even the cat itself is a restriction. Throttle response is affected along with mid-range torque and a mpg gain also.
Inspection and registration goes by GVWR not the weight of your truck. I've lived in PA all my life. PA only does a visual inspection of emmision and exhaust components. If your truck has the cat removed it SHOULD FAIL inspection according to PA regulations for light duty trucks under 11,001lbs. GVWR. It is also in violation of federal law to remove a converter. 067 Pa. Code §*175.80.*Inspection procedure. You may be able to get around having a CAT in PA if your over 11,000lbs GVWR as I see no rules regarding it.Pennsylvania Code However it is still illegal to remove it under Federal Law.
The GVWR for an 04' F-350 SRW is 9700-9900lbs and a DRW is 11,000-11,500lbs.
#48
05-06-2008, 05:18 PM
"Do you have any dyno results? The 2-3mpg gain you claim by removing the cat is somewhat comical. I'm running headers"
woo hoo, you may also know that headers on this truck make just about no difference due to the cat restricting the exhaust downstream. I have headers also and noticed NO change from stock (minus sound). Also, the combination of parts I have added has attributed to the resulting mileage, not one thing alone. simpleton. (In all actuallity, the free spin hubs made the most difference)
"However it is still illegal to remove it under Federal Law."
However, everyone understands that here. We are all automotive enthusiasts and know what we should and shouldn't do and what we can get away with. I just told you a way around the inspection criteria for the state of PA, one that I have experienced for three years of inspection for, not for the US.
"If your truck has the cat removed it SHOULD FAIL inspection according to PA regulations for light duty trucks under 11,001lbs. GVWR"
Damn, you are good "Sherlock", but if they can't look for it, they can't look for it. The emissions exemption states they cannot inspect for the parts to be installed and unfortunatley that number you just stated is actually 9001 lbs. over that PA considers them to be heavy duty vehicles. (read farther)
"Why does every other "Tuner" on here say the from the factory the air/fuel ratio is lean, you say its rich."
Bold statement, but if you would have read my first post completely you would have noticed that I had a rich condition after the cat removal causing black smoke, I called Diablosport and they told me that the manufacturer created the rich condition to retain the efficiency of the catalyst and that was before I had even installed a tune.
"I stand by what I said, if the cat is not plugged and working properly there will be little performance gain and minimal mpg gains"
And there you stand, alone.
woo hoo, you may also know that headers on this truck make just about no difference due to the cat restricting the exhaust downstream. I have headers also and noticed NO change from stock (minus sound). Also, the combination of parts I have added has attributed to the resulting mileage, not one thing alone. simpleton. (In all actuallity, the free spin hubs made the most difference)
"However it is still illegal to remove it under Federal Law."
However, everyone understands that here. We are all automotive enthusiasts and know what we should and shouldn't do and what we can get away with. I just told you a way around the inspection criteria for the state of PA, one that I have experienced for three years of inspection for, not for the US.
"If your truck has the cat removed it SHOULD FAIL inspection according to PA regulations for light duty trucks under 11,001lbs. GVWR"
Damn, you are good "Sherlock", but if they can't look for it, they can't look for it. The emissions exemption states they cannot inspect for the parts to be installed and unfortunatley that number you just stated is actually 9001 lbs. over that PA considers them to be heavy duty vehicles. (read farther)
"Why does every other "Tuner" on here say the from the factory the air/fuel ratio is lean, you say its rich."
Bold statement, but if you would have read my first post completely you would have noticed that I had a rich condition after the cat removal causing black smoke, I called Diablosport and they told me that the manufacturer created the rich condition to retain the efficiency of the catalyst and that was before I had even installed a tune.
"I stand by what I said, if the cat is not plugged and working properly there will be little performance gain and minimal mpg gains"
And there you stand, alone.
#49
05-06-2008, 05:34 PM
"Do you have any dyno results? The 2-3mpg gain you claim by removing the cat is somewhat comical. I'm running headers"
woo hoo, you may also know that headers on this truck make just about no difference due to the cat restricting the exhaust downstream. I have headers also and noticed NO change from stock (minus sound). Also, the combination of parts I have added has attributed to the resulting mileage, not one thing alone. simpleton. (In all actuallity, the free spin hubs made the most difference)
"However it is still illegal to remove it under Federal Law."
However, everyone understands that here. We are all automotive enthusiasts and know what we should and shouldn't do and what we can get away with. I just told you a way around the inspection criteria for the state of PA, one that I have experienced for three years of inspection for, not for the US.
"If your truck has the cat removed it SHOULD FAIL inspection according to PA regulations for light duty trucks under 11,001lbs. GVWR"
Damn, you are good "Sherlock", but if they can't look for it, they can't look for it. The emissions exemption states they cannot inspect for the parts to be installed and unfortunatley that number you just stated is actually 9001 lbs. over that PA considers them to be heavy duty vehicles. (read farther)
"Why does every other "Tuner" on here say the from the factory the air/fuel ratio is lean, you say its rich."
Bold statement, but if you would have read my first post completely you would have noticed that I had a rich condition after the cat removal causing black smoke, I called Diablosport and they told me that the manufacturer created the rich condition to retain the efficiency of the catalyst and that was before I had even installed a tune.
"I stand by what I said, if the cat is not plugged and working properly there will be little performance gain and minimal mpg gains"
And there you stand, alone.
woo hoo, you may also know that headers on this truck make just about no difference due to the cat restricting the exhaust downstream. I have headers also and noticed NO change from stock (minus sound). Also, the combination of parts I have added has attributed to the resulting mileage, not one thing alone. simpleton. (In all actuallity, the free spin hubs made the most difference)
"However it is still illegal to remove it under Federal Law."
However, everyone understands that here. We are all automotive enthusiasts and know what we should and shouldn't do and what we can get away with. I just told you a way around the inspection criteria for the state of PA, one that I have experienced for three years of inspection for, not for the US.
"If your truck has the cat removed it SHOULD FAIL inspection according to PA regulations for light duty trucks under 11,001lbs. GVWR"
Damn, you are good "Sherlock", but if they can't look for it, they can't look for it. The emissions exemption states they cannot inspect for the parts to be installed and unfortunatley that number you just stated is actually 9001 lbs. over that PA considers them to be heavy duty vehicles. (read farther)
"Why does every other "Tuner" on here say the from the factory the air/fuel ratio is lean, you say its rich."
Bold statement, but if you would have read my first post completely you would have noticed that I had a rich condition after the cat removal causing black smoke, I called Diablosport and they told me that the manufacturer created the rich condition to retain the efficiency of the catalyst and that was before I had even installed a tune.
"I stand by what I said, if the cat is not plugged and working properly there will be little performance gain and minimal mpg gains"
And there you stand, alone.
#50
05-06-2008, 05:46 PM
You wanna go that way eh? Weel, for one I have no dyno runs, it's all seat of the pants here and with 180,000 miles on the clock of my truck, I can feel gains, anyone could. If you weren't such a sarcastic putz I might continue, but now as I see how you are, I'm done.
PS: Who the **** has a dyno in the US large enough to support a lifted f-350 cc swb? last one I was on could barely fit my 95 t-bird.
PS: Who the **** has a dyno in the US large enough to support a lifted f-350 cc swb? last one I was on could barely fit my 95 t-bird.
#52
05-06-2008, 05:50 PM
#53
05-06-2008, 05:56 PM
#54
05-06-2008, 06:17 PM
"If you would have read this "067 Pa. Code §*175.80.*Inspection procedure." you would have noticed that the inspection is for passenger cars under 9001 lbs. Try again."
I've read it several times already. Please point me into the right direction. 067 Pa. Code §*175.80 is under "Subchapter E Passenger Cars and Light Trucks" I am not seeing the 9,001lb GVWR restriction you mention.
I've read it several times already. Please point me into the right direction. 067 Pa. Code §*175.80 is under "Subchapter E Passenger Cars and Light Trucks" I am not seeing the 9,001lb GVWR restriction you mention.
#55
05-06-2008, 06:26 PM
#57
05-06-2008, 07:24 PM
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Lifted truck on a dyno. Impressive numbers too.
https://www.ford-trucks.com/forums/7...p-882-fpt.html
https://www.ford-trucks.com/forums/7...p-882-fpt.html
