Cat by-pass

[SteveA]

First/one off. Polished stainless. What do you think? They will bolt up to either the stock or Borla muffler.

 

[Clax]

Looks nice. Do you have any sound files of the car using the stock muffler and Borla muffler?

 

[SteveA]

No sound files, sorry.
The pipes are on a friends car with a Borla. From the back/outside the sound increase is very noticable in particular when punched. Form the inside I was suprised it's not that different from having the Borla only.

 

[TEXAS GT]

When can we buy them?

 

[SteveA]

I believe right now. I don't have anything to do with it but I can PM you there number. (Not sure if there is an issue with posting the number here, he isn't a member).

 

[Gulf GT]

I am guessing that people are opting for the cat bypass pipes because they don't want to put on the long tube headers for some reason. Is this because with the long tube headers it will be more difficult to put back to stock when you're not racing (wink wink)? For optimum exhaust performance wouldn't you want the headers? The difference in price is meaningless to all us at this point. Just want a good opinion from all the experts here. I don't know squat about this stuff, and I am tempted to put the long tube headers with the Borla exhaust or just go with the rear exit header system. From what I've heard the cat delete pipe with Borla exhaust isn't too loud, so a little louder can't be too bad right? Why make up a cat delete pipe, just go with the Ford Racing stuff and call it a day. Surely Ford Racing has a good idea of what they are doing. Help me out here.

 

[BlackICE]

Is this because with the long tube headers it will be more difficult to put back to stock when you're not racing (wink wink)?

You hit the nail on the head! When not racing how much time would it take to replace the headers used for racing only with the stock exhaust, compared to swapping out the cat delete pipes for the cats? Can the headers be installed and removed easily with the belly pans off?

BlackICE

 

[AMB]

Cat By Pass

You will still need the O2 sensors installed for the ECM to work CORECTLY !!!

AMB

 

[nota4re]

FWIW, California waives the emissions testing requirement for 6-years on a new car purchase. Also, any transfer of title within 4-years or purchase will not require a smog certification (test).

 

[BlackICE]

CA waviers are only if you bought the car from a dealer in CA, otherwise you have to smog every 2 years!

BlackICE

 

[BlackICE]

You will still need the O2 sensors installed for the ECM to work CORECTLY !!!
AMB

My understanding is that you can trick the system by taking off the o2 sensors on the cats and jumper the sensor wire with a resistor.

BlackICE

 

[AMB]

BlackICE

That is ONLY for the REAR O2 senser !! You still NEED the FROUNT O2 senser for the ECU to work !!!

AMB

 

[SteveA]

The 02 still threads into these pipes.
The reason why I would want these vs headers is as follows. As I understand the headers don't add much if any power gain over the stock manifolds and are a pain in the butt to install and remove. The cats help add to the heat soke issue and do restrick some. These cat delete pipes are very easy to install but should have the computer reflashed. This is the only reason I am on the fence. I'm not ready to say goodby to the warrenty.
As for the sound increase...I have the borla only but have heard a car with these pipes on also with a borla.
I think most agree the car is a bit quite with the DOT stock muffler and it is a pig at 65lbs. Most do like the sound increase with the borla, however the borla + headers sounds like the back stretch at Le Mans from what I have read. The cat delete IS louder than the borla alone but I THINK not as loud as headers. Cat delete pipes and borla = less heat and weight and increases air flow through the engine bay and offers a bit less exhaust restriction.
When you hear the delete pipes with the hood open there isn't anymore noise from the engine compartment just more rumble out the back. I don't think the same can be said for headers.