When I bought my Spyder (8 years ago!) the exhaust had previously been altered from the standard arrangement. The silencer was mounted from the engine frame rather than using the dimpled brackets off the engine. That part had been quite well executed but the rest from the manifold to the silencer was a bit nasty but as it worked I lived with it. It has deteriorated though and the downpipe fractured this spring. I welded it up to get me through the summer but it was always a temporary fix so I've been squirrelling bits of exhaust for a while to come up with something more suitable. Thanks to the various donors!
I recently bought a complete engine/gearbox with ancillaries that had come out of a Spyder (the one Westfield was going to convert to electric). Looking at the downpipe that came with that made me realise just how bad my downpipe was! I was going to try to build a new system based around that downpipe but a friend had a Lotus Elise S2 (K series) downpipe he didn't need and let me have it so I've used that instead. A section from a MGTF system I'd kept was cut to make a short straight bit with a flexi and then that joined to a 180 bend back to the silencer with 2 bolt flanged connections throughout for easy future removal.
Old and new downpipes - really shows how poor the old downpipe was!
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downpipe comparison.jpg [ 510.57 KiB | Viewed 425 times ]
The rest of the system before and after. The 180 on the left is set almost vertical going into the previous can location directly above.
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exhaust before and after whole.jpg [ 482.96 KiB | Viewed 425 times ]
The way it now hangs means the outlet is central in the rear clam hole which it never was before!
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tail central.jpg [ 133.74 KiB | Viewed 425 times ]
I took it out for a drive and it sounds and feels much better. It clearly pulls better mid range so the old downpipe must have been upsetting the flow with the too short secondaries. Also, a vibration I'd always had at 3000rpm has much reduced so it must have been an exhaust resonance before.