Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Exhaust manifold 2000 Morgan plus 8 4.0

Any suggestions for an aftermarket exhaust manifold as looking for better performance and more aggressive sound.Also looking for feedback from people who have done.

If you want to continue to use the catalysts I think the main option for headers is the Librands system. (easily available on this side of the pond , I don't know about yours)

This is now a tubular system which exits through the hole in the chassis on each side (originally it was a crossover system , which was good for long primaries , but very complex, and heat under the sump is not a good idea in hot climates)

The manifold itself will certainly help with breathing, and power development, the sound is dependent upon the exhaust system from there backwards.

Firstly catalysts , you can delete these, but this then may fail emissions tests, so most of us keep them. You can source catalysts with a lower cell count (200 v 400+) these will help but are more prone to fouling with duff fuel.

Secondly silencers, the standard MMC product at this time was abysmal, and almost any alternative is better. You can get these made up locally, but here they are available from Librands , a straight through design.

Lastly rear and tail pipes, the resonators that MMC fitted do not really work , but they look good to some, so optional. I would go with a straight through system which is shaped to miss the rear wheels and exits at the rear with a simple flared tip.

Others opt for a side exhaust coming away from the silencer just in front of the rear wheel on each side . This will certainly give a much louder sound, especially on the overrun , but can get tiresome on long journeys.

Plenty of options , your choice may be limited by what is available , or can be made up locally.

I have a 2000 4.6 and just had fitted the Librands manifolds and noisy silencers with decat pipes.

The sound is epic. It came with horrid brackets on the rear tailpipes which were themselves polished with roll tips. I no likey.

When I changed to neater straight cut 3” pipes the sound became deeper and more crackles on over run. Sensational.

The USA may be different to the UK for emissions. Here, if a car (post ‘93?) was fitted with a cat then it must be there and actually seen at MOT, irrespective of passing emissions. No cat = automatic fail. If your emissions are ok then a dummy cat might work!
I have a 2002 car with Gems management. It has O2 lambda sensors before and after both cats. That set up might need sorting in the management system if lambda readings go out of spec if the cats are removed. Anyone had any experience?

Friendly MOT man required

Thanks guys seems like librands is the supplier I keep hearing.In New Jersey USA we have to go for emissions testing every 2 years so probably need the cats.

The lambda sensors/Gems set up can cope with Cat removal.

For real?? I can smell the gasses

My '02 has been running without Cats for about 15 years. No smell of gasses - at least not from the car! (The Gems is a MUCH more sophisticated system than the Hotwire)

When a friend of mine upgraded his manifolds from the original cross-over system, he forgot to cross over the lambda sensors as well. I took a lot of head scratching to work out why the engine was not running properly!