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shogun
11-15-2007, 08:48 PM
http://www.bimmerboard.com/forums/posts/440862
of course he also changed the piston rings on his 750, but now Pat finally passed the CA smog test.

What wonders me, is that there are apparently no companies in USA which sell the cat metal cores only. In Germany there are companies which repair cats for a fraction of the price of a new one (complete cat with housing), they cut off the cat housing, remove the old cat insert, weld in a new one, weld the housing, done. Usually the repaired cat is returned within 24 hours.

cat core inserts
http://www.uni-kat.de/katalog.htm

attack eagle
11-15-2007, 11:46 PM
AFAIK my interpretation of the statute is that it is illegal to tamper with the cats... they either must be replaced as a whole assembly or left alone, repair is a foreign concept since it could lead to "tampering".

Robin-535im
11-15-2007, 11:50 PM
AFAIK my interpretation of the statute is that it is illegal to tamper with the cats... they either must be replaced as a whole assembly or left alone, repair is a foreign concept since it could lead to "tampering".
Plus, it would make way too much sense... :)

BTW - who among us hasn't at one time or another opened up their cat from the top and removed the guts?

Sam-Son
11-15-2007, 11:52 PM
sorta on topic anybody know where I can get some high flow cats?

attack eagle
11-15-2007, 11:58 PM
Plus, it would make way too much sense... :)

BTW - who among us hasn't at one time or another opened up their cat from the top and removed the guts?


ME!!! ME!!!

I have 3 foot and 4 foot long Masonry bits... Just drill em out and then take it for a hard drive sans exhaust... the cat will crumble into pieces and be blown out... :D

*this is only what I have been told - I would never have any first hand knowledge of such an illegal and environmentally unfriendly practice, as cars are an easier target for the enviro-nazis than large industrial polluters. ;) *

Sam-Son
11-16-2007, 12:17 AM
ME!!! ME!!!

I have 3 foot and 4 foot long Masonry bits... Just drill em out and then take it for a hard drive sans exhaust... the cat will crumble into pieces and be blown out... :D

*this is only what I have been told - I would never have any first hand knowledge of such an illegal and environmentally unfriendly practice, as cars are an easier target for the enviro-nazis than large industrial polluters. ;) *
To hell with that More info please I know you would never do such a thing but I would. please tell me more

attack eagle
11-16-2007, 12:21 AM
If I were to do such a thing, I'd take my 4 foot masonry bit, drop the catback section and drill thru both layers of the cat element many many times from the rear opening. Like if I were going to break chunks out of it. takes little effort, just a fair bit o time.
It also adds a nice sporty growl to the stock exhaust.

Sam-Son
11-16-2007, 01:00 AM
If I were to do such a thing, I'd take my 4 foot masonry bit, drop the catback section and drill thru both layers of the cat element many many times from the rear opening. Like if I were going to break chunks out of it. takes little effort, just a fair bit o time.
It also adds a nice sporty growl to the stock exhaust.
4 foot? is the cat that long?

attack eagle
11-16-2007, 01:16 AM
you could probably get away with a 3 foot.

Sam-Son
11-16-2007, 01:19 AM
thanks for the info...I mean I know you don't really know any of this stuff 'cause you wouldn't delve into anything in the shady side of automotive modifications

shogun
11-16-2007, 01:37 AM
easy to remove, here pics from an E38 750 muffler (end) removal
http://static.ichflirt.de/user/pictures/5/71/d2ajrc9gxe404oxfmjdycasxbztutdx3ef7no2d27.jpg
http://static.ichflirt.de/user/pictures/7/19/04ajrc9p6ee40gnfhgzzpswnwyosvxu1659no6764.jpg
http://static.ichflirt.de/user/pictures/d/05/d6ejrc9rj3a3apqbwzmrlimsvszcsyr14c8no742a.jpg

well, I really am not a fan of such shadetree tuning.

That is better
http://www.bimmerboard.com/forums/posts/431168/
http://www.bimmerboard.com/forums/posts/358063
http://www.bimmerboard.com/forums/posts/357785/

Ross
11-17-2007, 10:24 AM
People pay upwards of a hundred bucks for all those pieces that went blowing out. Platinum.

attack eagle
11-17-2007, 03:18 PM
true but it would cost me $60 + time to cut them out and sell them. To me it is a wash.

Booster
11-17-2007, 04:50 PM
I just weld 2 ears to a quarter inch steel rod and attatch to a power drill and pummel away. Dump the contents into a large zip-loc baggy and sell.:)

But this is illegal to tamper and I would never do such a thing,:)
Vinny

genphreak
11-23-2008, 11:21 PM
I can get OE and replacement cats for 525/535 here in Australia for about $900AUD. Can probably get 750 ones also (just OE no doubt). Can ship to Japan too Erich- are you sourcing them cheaper yet?

;) With the Foriegn exchange rate so bad, (0.65c USD for 1 AUD atm) maybe this is not so bad...

shogun
11-23-2008, 11:48 PM
Thanks for the info. But I have some 750 lined up here as parts cars and all have good exhausts and cats. Usually in Japan (especially around Tokyo where I live=no snow, no salt in winter on the streets), there is no problem with corrosion for exhausts or cats.
If I buy new ones, I would buy the "racing" cores from Germany and weld the new ones in. That is also done in Japan and legal. Because the core is then new and the outer shell is still o.k.
Metallkatalysator / Rennkat (racing cat), rund, 200 oder 100 cpi, Rohrdurchm./pipe diameter) ca. 54 mm, bis ca./up to 1.600 ccm € 160.-

- Metallkatalysator / Rennkat ,rund, 200 oder 100 cpi, Rohrdurchm. ca. 57 mm, bis ca. 2.000 ccm € 185.-

- Metallkatalysator / Rennkat, rund, 200 oder 100 cpi, Rohrdurchm. ca. 67 mm, bis ca. 3.000 ccm € 220.-

- Metallkatalysator / Rennkat, oval, 200 oder 100 cpi, Rohrdurchm. ca. 52 mm, bis ca. 1.600 ccm € 165.-

- Metallkatalysator / Rennkat, oval, 200 oder 100 cpi, Rohrdurchm. ca. 64 mm, bis ca. 2.000 ccm € 190.-

- Metallkatalysator / Rennkat, oval, 200 oder 100 cpi, Rohrdurchm. ca. 64 mm, bis ca. 3.000 ccm € 228.-

http://www.uni-kat.de/katalog.htm

All single parts can be bought here,
metal cats
http://www.german-exhaust.de/shop/index.php/cat/c8_Metallkatalysatoren.html/XTCsid/00000000000006006130000000000000
ceramic cats
http://www.german-exhaust.de/shop/index.php/cat/c734_Keramikkatalysatoren.html/XTCsid/00000000000006006130000000000000

flex pipes , very nice
http://www.german-exhaust.de/shop/index.php/cat/c729_VA-Flexrohre.html/XTCsid/00000000000006006130000000000000

universal parts http://www.german-exhaust.de/shop/index.php/cat/c10_Universal---Teile.html/XTCsid/00000000000006006130000000000000

2fast
11-26-2008, 12:10 AM
Here in New Zealand we don't have CATS on our old Bmw's ,.;)

shogun
11-26-2008, 12:49 AM
Lucky guy. This or next week I have to bring my car to SHAKEN, the equivalent of MOT or automotive inspection, road certificate or whatever it is called around the world.
Every 2 years.
Before that I have to change 1 oxy sensor, found out that one of the 2 on the M70 is dead. Does not move the voltage at all.
I modified 1 of of the Jaycar CAT. NO. KC5195
Mixture Display Kit For Fuel Injected Cars
"Refer: Silicon Chip November 1995 This very simple kit will allow you to monitor the fuel mixtures being run by your car. This type of sensor is also known as an E.G.O. (exhaust, gas, oxygen) monitor. You can use it as a tuning tool, to help in vehicle modification or simply to see the behaviour of the engine control module. Indication is via 10 LEDs to show mixtures rich, lean and normal. The circuit connects to the EGO sensor mounted in the exhaust manifold and the cars battery. PCB, LEDs and components supplied"

http://www.jaycar.com.au/productView.asp?ID=KC5195&CATID=&keywords=fuel&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=

and added plugs to get it installed betwen the connectors of the oxy sensor and can see if the oxy sensor works.
Thanks to BigKriss for sending it to me from AUS.
Someone in Germany even installed it permanently in his car
http://www.bimmerboard.com/forums/posts/250490/