[pyro225]

Ok, so my car has what may appear to be a blocked cat (cant be 100% sure though) so what i plan to do is cut the cats off and put 2 simple bits of pipe (one size bigger than the cat pipe) in there place... i will fix these with 4 exhuast U clamps... If my problems are cured i will then buy 2 new (or low mileage) used cats and sleeve and weld them in place... Does this seem like a) a sensible plan before blowing money on cats b) a viable and fairly straightforward exercise... Dont worry about the SES light... i thik someone before me has had tat done, i had cylnder shut off and it didnt even come on!

 

[Bimmerbear]

Yes, you could do that, but why not just buy new cats in the first place? It seems like you're just making extra work for yourself.

Personally, if my state didn't care I'd just weld in the straight pipes and call it a day.

 

[E55AMG2]

You'll need SW to get rid of the SES light. There are aftermarket cats you can get for cheap.

 

[jt2ma71]

Seems reasonable. Just make sure you leave enough meat on the stock cats to weld them back in if they arent the problem. Like somoene else said, if my cats went and we didnt have Aircare here, i would take them out and not put them back in lol. Unfortunately we have Aircare.

 

[Hallatauer]

With my beast... Magnaflow Exhaust no cats. I mounted a spark plug anti fouling adapter on the post cat O2 sensors. I can go about 150 miles before it sets off the SES light.. plenty of time to have the state inspection and emissions done with a pass. They don't physically look for cats.. just as long as there is nothing on the OBDII.

 

[leem5]

If your in Cambridge (the original one) then Torque Flow supplied and fitted mine (100 cell) for just a couple of hundred.

 

[pyro225]

Torque cell? Are they racing cats or just straight replacements? Is your beast on eBay btw?

 

[leem5]

Torque cell? Are they racing cats or just straight replacements? Is your beast on eBay btw

Torque Flow, just outside Birmingham. Yes they are classed as 'race' cats, there's no problem with these in the UK, the car will pass emissions no bother for your MOT.

Mines not for sale, unless the misses has put it up!!

 

[pyro225]

ok cool... do you know the diameter of the pipe the cats sit on?

 

[vantaam5]

63.5mm aka 2.5"

 

[pyro225]

so what size pipe goes over it? as asleeve

 

[vantaam5]

so what size pipe goes over it? as asleeve

Logically a sleeve that has 63.5mm inner diameter...

 

[OJwerks]

is your car a Euro spec ?? not sure about the m5, but the Euro 540i does not trigger a CEL when you remove the cats. ask me how i know

 

[pyro225]

Sorry to bring this back from the grave but... If I have complete useless cats or they have been knocked out... And the rear sensors are reading the
Same as the front what would you expect to happen if no software had changed?

 

[ard]

Sorry to bring this back from the grave but... If I have complete useless cats or they have been knocked out... And the rear sensors are reading the
Same as the front what would you expect to happen if no software had changed?

Check engine light, code for 'cat efficiency below threshold' or some such

 

[pyro225]

So not the cat damage protection fault I'm getting?

 

[FlyBMW]

Does deleting cats bring any power gains?
All exhaust stock except Eisenmann Sport cans.

 

[ard]

So not the cat damage protection fault I'm getting?

What cat damage protection fault?

Does deleting cats bring any power gains?
All exhaust stock except Eisenmann Sport cans.

No, the cat is not a major restriction. The exhaust manifold is...

 

[pyro225]

Ard - the fault I refer too on the please help me post when it goes into limp mode - only resurrected this pos as it was about cats

 

[E55AMG2]

You've had gutted cats this whole time? Why didnt you mention that to Sal when you were at evolve? This could be the cause of your whole issue...I'll bet you if he turned off the rear O2 monitoring, your car would stop kicking into limp mode.