986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - retrofitting non-cat manifolds to later models

Dave80GTSi · 02-22-2018, 07:42 AM

I did a search on this topic, but did not find anything.

The later model 986 exhaust manifolds with integral cats are a flow horrorshow. See enclosed pinch point, shown in second picture.

Putting the differing oxygen sensor location issues aside for the moment, has anyone ever retrofitted a later model (like, just for a random theoretical example, a 2000 S) with the exhaust system from an earlier model 1998-1999 or so non-S model with no-cat manifolds?

My question centers around whether or not the early non-cat manifolds (first picture), combined with their complimentary secondary pipes which run from the manifold outlet flange to the rear muffler inlet, are dimensionally interchangeable between the early no-cat and the later cat models.

Is it all just a simple bolt-on?

Thanks - DM

02-22-2018, 07:42 AM	#1
Dave80GTSi Registered User Join Date: Sep 2016 Location: Central Ohio Posts: 399	retrofitting non-cat manifolds to later models I did a search on this topic, but did not find anything. The later model 986 exhaust manifolds with integral cats are a flow horrorshow. See enclosed pinch point, shown in second picture. Putting the differing oxygen sensor location issues aside for the moment, has anyone ever retrofitted a later model (like, just for a random theoretical example, a 2000 S) with the exhaust system from an earlier model 1998-1999 or so non-S model with no-cat manifolds? My question centers around whether or not the early non-cat manifolds (first picture), combined with their complimentary secondary pipes which run from the manifold outlet flange to the rear muffler inlet, are dimensionally interchangeable between the early no-cat and the later cat models. Is it all just a simple bolt-on? Thanks - DM Attached Images __________________ 2000 Ocean Blue Boxster S 1980 Ferrari 308 GTSi 2019 Alfa Romeo Giulia Ti Sport AWD