KV exhaust

Mellis46 · 07-06-17, 01:18 PM

The back box on my 1989 B3 90 2.2 KV quattro has rotted through again where the intermediate pipe meets the back box. MOT is looming!

I struggled last time to find a back box for it hence plumping for a CES supplied Bosal jobbie, but this one has only lasted about 6 years, now they seem to be even thinner on the ground. I perhaps should have gone for a stainless one back then but...

Question: could the (more easily obtained) back box from a 90 quattro 20v be a straight swap? The triangular flange where the back box bolts up certainly looks similar. Part numbers are subtly different, but then so are the tail pipes. Something is niggling me the intermediate pipe diameters might be different...? I'm only talking back box, not going into cats or downpipes or anything else I know is different further up the system

I suppose i could get one made, have heard of people having issues with clearance that mean they keep having to go back for "fettling" however.

Anyway, thanks for any input anyone can provide!

mikes2 · 07-06-17, 03:57 PM

pipe size is different on the 20v - 60mm instead of 55mm on the 10v.

you may get away with it bolting up ok

quattrodave · 07-06-17, 04:10 PM

Quote:

Originally Posted by mikes2

pipe size is different on the 20v - 60mm instead of 55mm on the 10v.

you may get away with it bolting up ok

A few years ago I managed to fit a NOS geniune Audi S2 rear box to my dads KV engined B3 90 quattro (got it at the then bargain price of £90), regretfully we sold the car about 4 weeks later before I had chance to swap it for one of my other non geniune spare ones. So yes it can be done I think we used a section of the (uncorroded) original exhaust as a packer with lots of exhaust cement to ensure a tight fit.

If you really struggle to find a rear box I have a spare 60mm (from a V6 coupe quattro) I can sell you.

Mellis46 · 07-06-17, 07:23 PM

Mike, Dave, Thanks for the info, appreciated

Will see what i can sort

Tun · 08-06-17, 07:06 AM

Mark, this is the one I fitted to my 90 prior to selling it. The service was exceptional and I was really impressed with the quality. As Mike says the bore is bigger but it does show the part number for the KV (893 253 609 P).

http://www.ebay.co.uk/itm/1218754050...%3AMEBIDX%3AIT

Mellis46 · 08-06-17, 07:29 AM

cheers Royston, will take a look

07-06-17, 03:57 PM	#2
mikes2 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Polmont Posts: 2,617	pipe size is different on the 20v - 60mm instead of 55mm on the 10v. you may get away with it bolting up ok __________________ 1991 90 quattro 20v sport 1991 90 quattro

07-06-17, 07:23 PM	#4
Mellis46 Aero Advocate Classic Audi Club Member Join Date: Aug 2014 Location: Lancashire Posts: 1,448	Mike, Dave, Thanks for the info, appreciated Will see what i can sort __________________ -1987 90 2.2E / Sapphire Blue (Rest in Pieces) -1989 90 quattro with Sport Equipment / Satin Black -1997 A4 Avant quattro TDI 110 / Tropical Green (Sold)

08-06-17, 07:06 AM	#5
Tun Grown up member Classic Audi Club Member Join Date: May 2011 Location: Buxton Posts: 745	Mark, this is the one I fitted to my 90 prior to selling it. The service was exceptional and I was really impressed with the quality. As Mike says the bore is bigger but it does show the part number for the KV (893 253 609 P). http://www.ebay.co.uk/itm/1218754050...%3AMEBIDX%3AIT __________________ 1988 MB quattro 2012 S4 Avant

08-06-17, 07:29 AM	#6
Mellis46 Aero Advocate Classic Audi Club Member Join Date: Aug 2014 Location: Lancashire Posts: 1,448	cheers Royston, will take a look __________________ -1987 90 2.2E / Sapphire Blue (Rest in Pieces) -1989 90 quattro with Sport Equipment / Satin Black -1997 A4 Avant quattro TDI 110 / Tropical Green (Sold)