mike77

'your great grandkids will thank you.'

Pretty sure cats increase fuel consumption and co2 emissions. The way i see it I've done the world a favour

Mike Frye

They make CO into C02, but I'm pretty sure that's a net gain in the environment department. Not sure about increasing fuel consumption. I disagree on this point.

The car was shipped with one, and even if it's over 25 years old and they don't test where you are, I'm pretty sure it's illegal to tamper with or remov this type of equipment if it's originally shipped with it.

hwyengr

Absolutely. CO and HC make smog, and that's far, far worse than increased CO2 production.

davek9

First this thread ONLY applies to MY's '85 and '86 (not 86.5 as they have same exhaust system as S4 w/ exception of the exit out the back, not the side like all OB's).

So on my '85 w/ X pipe, no CAT's , I'm looking to build a "CAT" back using a RMB.

Any recommendations on what Resonator (or two small side by-side) that would fit in place of the "two in, two out" stock single I could /should use that still would be street friendly?

edit: my 86.5 is an x , no-cats, stock dual resonators(like an S4), w/ RMB and I'm completely happy w/ the sound (although at times it could be a bit too loud if that is possibly LOL ).

Thank you,

Dave

PelicanParts.com

We have a great Tech Article about exhaust upgrades for your vehicle here.

You can also take a search through our parts catalog here.

-Luccia

davek9

Thank you for the suggestion and links ^^^^

Unfortunately this in not a "Bolt on" replacement part, on the '85/'86 928 it is all one unit that runs from the CATS to and including the rear muffler. So two 2.5 inch pipes welded into a two in two out res, than two pipes welded to the large rear muffler.

Unlike the later years (86.5 and up) where each part is separated by clamps.

I'm seeking a single component (or two) that will fit in the space provide for the stock resonator.

Thank you,

Dave

Preston2207

So long story short. Does anyone have an X pipe sitting in the garage for MY 85 that's taking up space!! Looks like I'm about to purchase one. I have pretty good welding skills and a welder so the catback will be all "Custom Preston Pipe"

GUTTER-BOY

davek9 and Preston,

I went with the Cherry Bomb Extreme muffler and Vibrant 1331 exhaust tips on my early-'86 wide body 928. I think together they were about $120, and my local Midas welded it up for about $100. There aren't too many mufflers that will fit our cars, so I got lucky and this worked out well for me.

The exhaust sounds good without being too loud, with no drone at cruising speeds. When you accelerate hard you will definitely turn some heads (in a good way). The only issue is that the red muffler lost it's color after about a month. My car is black with a red interior so I didn't mind the red on the muffler, but losing the color might actually be good for those who don't want the red. It turned an off black due to the heat and "disappears" under the car unlike the red, which was pretty visible while the paint was on it.

Preston2207

Gutter boy, are you're referring to the resonator and rear muffler combo in
The MY 85 & 86. What did you do About your cats?

SMTCapeCod

Just ditch plan 'A' and go with high flow cats, no intermediates and an RMB. Actually, that would be silly, best to run a mandrel set of pipes from low cell count cats to factory muffler,and get rid of that pinch under the crossmember.
Maybe try one of those intersting UK resonated RMBs....

I tried two custom mufflers in place of the midstream resonator on an 85 I had years ago, one by Brullen (now out of business) and one by stainless specialties (or similar-- in Fla). Neither made much difference from the stock. I also had the latter do a narrow, long dual in/dual out to replace the cats- had them place an O2 bung in the front and had a mixing chamber there. The ceramic packing seemed to hold up OK for the time that I ran it.

I fit stock S4 resonators to my former '83 and that worked fine after addition of pass side mounting point. I ran them to a stock Euro-spec 86.5 final. That was pretty quiet, but you could route to an 86.5 RMB instead.

My current 86.5 has small custom aftermarket midstream resonators, and a magnfalow X snuck in between the battery case and cross member.

PelicanParts.com

Apologies, my post was directed to the OP WyattsRide.

GUTTER-BOY

Preston,

Other than the muffler, I left everything else stock (cats, x-pipe, etc.). I didn't want to risk failing emissions testing, even though I passed the e-test when I first bought it and it didn't even have a muffler on it. The PO had a nasty homemade muffler by-pass. It was too loud without a muffler and was too "raw" sounding. The Cherry Bomb sounds great but it might be too loud if you want a relatively stock sounding exhaust note.

Preston2207

Ok! From all the ideas I think I'll have a custom made "test" pipe that will replace the cats and have a O2 bung installed. Can't see spending 600+ on a X pipe. I may even just have an x made at a local shop.

medipedicman

I have an original X pipe that I "HOPE" to use on a Euro S build next month. If I cannot use it on this build I will be selling it. Won't know till end of May as this will be the final step.

Preston2207

Well contact me when you're ready to sell. My quest now is to see if I can't get a local shop to make a custom x pipe and I'll take it from there. if they want around the same $ that it would be to order one then I will wait! I have had custom exhaust on every vehicle I've ever owned and I just can't see an X costing 600!!