Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Exhaust question

So what does that do to the ecu?

Hi Lightspeed,

There are multiple small holes in each rear baffle. After drilling out the front baffle, I was very happy with the exhaust note, but I wanted to release alittle more exhaust back up pressure without significantly changing the exhaust sound. So I enlarged all the holes in the rear baffle slightly using a 5/16” black oxide 12” aircraft drill bit. I’m now happy with my exhausts and won’t be making any further changes. You can see there is a central theme in my posts about the exhaust. Yes, I want the engine to run well but the exhaust note and how it enhances my overall driving experience with the M3W is very important to me. And I certainly understand sound is very subjective and we all have different likes and dislikes. The Morgan Aero Racing Stage 1 and the Garage 56 Stage 1 are all excellent mods. For any new M3W owner having a less restrictive exhaust and higher flow air filter is a must as others have stated as well. There’s more than one way to “skin a cat”.

Magnaflow......the name says it all! You can do it for around $300 and save the originals.

http://www.talkmorgan.com/ubbthreads.php/topics/607920/1

Sorry High Noon I forgot about your exhaust.

You also have a very nice solution to the stock restrictive exhaust with excellent exhaust note.

Thanks Sportster. And High Noon, that is fine welding you did and if i was a welder of your caliber i surely would have gone that route.

Here is a question for the G56 muffler owners; are they a straight through with no baffles?

Yes, G56 are true straight through with just an absorption silencer. They have much larger silencers than the other exhausts I've seen but are relatively quiet. Original MMC sports exhausts were straight through with a small silencer but were desperately noisy, as was Krazy Horse's first attempt at a system.

Thanks Calum. The Magnaflow , if given the same size can, would produce a similar sound probably.

Nothing, as o2 sensors sit before cats?

Good point, but it would change the airflow in that area of the pipes, so maybe the ECU adapts to it.

The ECU has the capability to separately adapt both the timing and the fuelling. As standard both functions are on and the adaptive range will cope with a stage 1 tune of air filter and derestricted exhaust (baffelectomy, MMC, G56 etc).

If you can get an unlocked ECU and are able to get a dyno tune (eg at Krazy Horse) then the timing adaptive would be left on but the fuel adaptive switched off and the fuel map optimised on the dyno.

For stage 2 (569 cams) the adaptive fuel will go out of limits at higher revs/wider throttle and throw a check engine light. This is why you'll need an unlocked ECU and a modified fuel map. The S&S ECU has a selectable default map which will cope with the higher lift cams or companies such as KH and G56 provide a custom map. Again, a session on the dyno will allow this default map to be tweaked to your individual engine and set-up.