Ok so Im gettin ready to replace my catalytic converter. I have a Bonez High Flow cat, but I wanna go back to OEM so I can run in E-Stock for autocrossing. I was looking in the Victoria British Catalog and it lists for 86-92 w/o turbo 3 different part numbers.

It lists:

Replacement Converter #1
Replacement Converter #2
Replacement Converter Rear "A"

"A" means "with air tube"

They are all the same price, but what does it mean by listing 3 of them. Are they all parts of a whole or just different types. Anyone have an Idea, or should I just pick up a used one, or go to mazda and ask for one. ??

My car is a 1990 GTUs

Thanks

Jake

 

Im going into the dealer now for my appt. to have my mousebelt checked out. Maybe Ill ask them about getting a new cat.

 

The N/A has 3 cats from the factory. The main cat (Rear most) has an air tube.

 

meaning I need to purchase all 3...

 

Yes, there are two pre cat's and one main cat with a split air pipe. Frankly, i'd get an oem "alternative" such as a universal cat from autozone. They are farely cheap, and most muffler shops should be able to weld them in. I don't see how putting a non high flow cat on your car regardless of which brand should affect which class you run in. Then again, i don't have a rule book to read.

-Justin

 

Not all of them had 3 cats. Most S5s I've seen only have two plus a downpipe-type-pipe.

You might want to save some money by getting the whole thing used.

EDIT: I just checked, I sitll have my stock main cat and downpipe, I just dont have the middle (pre) cat. I'm sending you a PM to see if I cant sell them to you

 

**the rule book for stock class says anything downstream beyond the header/manifold and catalytic converter, if so equipped, may be substituted.

And from friends Ive talked to, and from my understanding that basically means, the header and cats must be stock, or stock replacement models that offer no performance gains. This is my problem because my Bonez Highflow doesnt really meet stock equiv.