DEC Catalytic Converters

 

Why DEC - For the most part, I am a strong proponent of using factory or OEM (original equipment manufacture) parts on my cars. However, when it comes to catalytic converters, because of the huge price difference between "genuine" and "aftermarket", many folks will want to consider a quality, non-factory replacement.

Most of the aftermarket catalytic converters I've run across over the years consist of a small (ie, noisy & somewhat restrictive) converter welded to a set of pipes that are bent into shape to fit the cars. In the bending process, the diameter of the pipes changes with each bend. With each external die bend, the pipe can shrink as much as 15%. This will cause restriction in exhaust flow. The preferred way to make the bends is through "mandrel forming" in which a female multiple piece die is inserted into the pipe to prevent compression of the metal at the bend. This is how quality headers are constructed. Most DEC cats have mandrel bends.

The other features to look for in a catalytic converter are heavy gauge construction (14 gauge), proper heat shielding around the converter, and "high flow" design. DEC cats meet these criteria and offer superior flow and lower sound levels than other aftermarket units I've evaluated.

Put aside the cost issue and I'll still take a factory BMW catalytic converter over any aftermarket unit. If you live in California and own a 1996 or later model, DEC now offers CARB approved ("50 state") converters for use on your BMW at significant savings and longer warranty compared to the factory part.

 

Why Purchase from Ultimate Garage...

Tech Support - If you've purchased a DEC catalytic converter from Ultimate Garage and require technical support (eg, "fault code issues", "rattles", "fitment", "meltdown", etc), I'll gladly send you my troubleshooting tips page if you suspect a problem. I can also be reached by phone at 201-262-0412 to personally answer your questions...you won't be directed to a "call center" halfway around the world.

Freight - All converters are shipped with a flat $10.00 freight charge anywhere in the continental US.

Hardware - Most BMW catalytic converters (excluding 8-cylinder applications) include the following:

  • Catalyzer gaskets between the manifolds & converter

  • Copper plated 10mm manifold locknuts

  • Muffler seals & gaskets (for converter to muffler attachment....if required)

  • Muffler to converter thru-bolts with gr10 flanged locknuts (if required- excludes bolts over 55mm in length, typically used with compression springs)

 

 

Shipment - most catalytic converters will be drop-shipped from DEC's California warehouse with hardware supplied from Ultimate Garage in NJ. All NJ sales are subject to 7% sales tax.

Warranty - all DEC catalytic converters come with a 5yr/50,000 mile warranty on the stainless steel shells and a 2yr/25,000 mile warranty on the ceramic bricks (an internal rattle or failed emission test usually indicates a problem with the bricks).

DEC's new 50-state converters carry a full 5yr warranty on the complete unit. The customer is responsible for all freight (in-bound and factory return) on warranty replacements. Warranty is for the part replacement only...it does not cover labor or installation hardware!.

Important - fault code "cat efficiency too low" - DEC requires proof that the oxygen sensors are of reasonable age (ie, under 50,000 miles) and that the vehicle receive a fuel injection cleaning (de-carbonization) before they will even consider replacing a catalytic converter under warranty. A poorly operating or contaminated oxygen sensor can contribute to carbon build-up in the converter(s) and trigger efficiency fault codes.

 

BMW Model Application (call or email for pricing on items not yet in store)
 
DEC CATALYTIC CONVERTER-320i (80-83)
Catco CATALYTIC CONVERTER-320i (80-83) - Close-out Pricing
 
OEM CATALYTIC CONVERTER-318i (83-11/84) (original BMW) - Special pricing
DEC CATALYTIC CONVERTER-318i (12/84-85)
DEC CATALYTIC CONVERTER-318i/ic (90-91)
DEC CATALYTIC CONVERTER-325e (84-87)
DEC CATALYTIC CONVERTER-325i (87-91), 325e (88) - Close-out Pricing
DEC CATALYTIC CONVERTER-325ix (88-91)
 
DEC CATALYTIC CONVERTER-318i/ic (92-95)
DEC CATALYTIC CONVERTER-318i/is/ic (96-99) & 318ti (96-99)(E36) (49 State) - Details
DEC CATALYTIC CONVERTER-318i/is/ic (96-99) & 318ti (96-99)(E36) (50 State)
DEC CATALYTIC CONVERTER-323i/is (97-98) & 323ic (97-99) (49 state) - Details
DEC CATALYTIC CONVERTER-323i/is (97-98) & 323ic (97-99) (50 state) - Details
DEC CATALYTIC CONVERTER-325i (92-95)
DEC CATALYTIC CONVERTER-328i (96-3/98) (49 state) - Details
DEC CATALYTIC CONVERTER-328i (96-3/98) (50 state) - Details
 
DEC CATALYTIC CONVERTER-M3 (88-91)
DEC CATALYTIC CONVERTER-M3 (95)
DEC CATALYTIC CONVERTER-M3 (96-99) (49 state) - Details
DEC CATALYTIC CONVERTER-M3 (96-99) (50 state) - Details
 
DEC CATALYTIC CONVERTER-Z3/1.9 (96-98) (49 state)
DEC CATALYTIC CONVERTER-Z3/2.8 (-99) (49 state) - Details
 
DEC CATALYTIC CONVERTER-528i (79)
DEC CATALYTIC CONVERTER-528i (80-81)
 
DEC CATALYTIC CONVERTER-528e (82-2/87)
DEC CATALYTIC CONVERTER-528e (3/87-88)
DEC CATALYTIC CONVERTER-533i (82-84 Std Trans) & (82-83 Auto Trans)
DEC CATALYTIC CONVERTER-533i (9/83-on Auto Trans)
DEC CATALYTIC CONVERTER-535i (85-88) (Std/Auto) - Details
DEC CATALYTIC CONVERTER-M5 (87-88)
 
DEC CATALYTIC CONVERTER-525i (89-90)
DEC CATALYTIC CONVERTER-525i (91-95) (including Touring)
DEC CATALYTIC CONVERTER-535i (89-93)
DEC CATALYTIC CONVERTER-530i Left (93-95)
DEC CATALYTIC CONVERTER-530i Right (93-95)
DEC CATALYTIC CONVERTER-540i Left (93-2/94)
DEC CATALYTIC CONVERTER-540i Right (93-2/94)
DEC CATALYTIC CONVERTER-540i Left (3/94-95)
DEC CATALYTIC CONVERTER-540i Right (3/94-95)
DEC CATALYTIC CONVERTER-M5 (91-93)
 
DEC CATALYTIC CONVERTER-528i (97-98) (49 State) - Details
DEC CATALYTIC CONVERTER-528i (97-98) (50 State) - Details
DEC CATALYTIC CONVERTER-540i Left (96-98) (50 State) - Details
DEC CATALYTIC CONVERTER-540i Right (96-98) (50 State) - Details
 
DEC CATALYTIC CONVERTER-633i (80-81)
DEC CATALYTIC CONVERTER-633i (82-84 Std Trans) & (82-83 Auto Trans)
DEC CATALYTIC CONVERTER-633i (9/83-on Auto Trans)
DEC CATALYTIC CONVERTER-635i (85-87) (Std/Auto) - Details
DEC CATALYTIC CONVERTER-635i (88-89)
DEC CATALYTIC CONVERTER-M6 (87-88)
 
DEC CATALYTIC CONVERTER-733i (80-81)
DEC CATALYTIC CONVERTER-733i (82-84)
DEC CATALYTIC CONVERTER-735i (85-87)
 
DEC CATALYTIC CONVERTER-735i (88-92)
DEC CATALYTIC CONVERTER-740i Left (92-94)
DEC CATALYTIC CONVERTER-740i Right (92-94)
DEC CATALYTIC CONVERTER-750i Left (88-94)
DEC CATALYTIC CONVERTER-750i Right (88-94)
 
DEC CATALYTIC CONVERTER-740i Left (95)
DEC CATALYTIC CONVERTER-740i Right (95)
DEC CATALYTIC CONVERTER-740i Left (96-98)(50 State) - Details
DEC CATALYTIC CONVERTER-740i Right (96-98)(50 State) - Details
 
DEC CATALYTIC CONVERTER-850i Left (89-94)
DEC CATALYTIC CONVERTER-850i Right (89-94)

 

 

Emails from Some Unhappy Customers - I've had positive comments from just about everyone regarding the quality of DEC but here are a few people who didn't quite get what they expected. Make sure you read these Customer Comments so you know what to expect from DEC and other mailorder converter purchases.