New Exhaust Query

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edd_barker
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New Exhaust Query

Post by edd_barker »

Hi all,

Flange snapped off my exhaust last week at 65mph which made it very loud all of a sudden. Still drove OK with just the manifold but fuel consumption did suffer a touch...

If I buy a maniflow small bore system, which inlet manifold do I need to let me run the original carb for a while until I get the 12G940 rebuild finished? Ideally I would fit the exhaust, put the same carb on a new manifold and have no re-tuning to do, until I get the larger carb and swap the engine and can set it all up then.

Or shall I just buy a new S/S system and use that?

I've never fitted an exhaust before so any hints tips would be much appreciated.

Thanks in advance,

Edd
bmcecosse
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Re: New Exhaust Query

Post by bmcecosse »

Just cut the inlet section off the old manifold, and use that meantime.
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edd_barker
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Re: New Exhaust Query

Post by edd_barker »

Ok I'll have a go at grinding that off, thanks!
bmcecosse
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Re: New Exhaust Query

Post by bmcecosse »

Cut first - well in to the part you want to throw away - then grind back the part you are keeping till it fits nicely without touching the exhaust. This alone will release another ~ 2 mighty horse power to your engine - by eliminating the 'hot spot' .
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edd_barker
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Re: New Exhaust Query

Post by edd_barker »

2 Horsepower, sounds good to me. Retune carb to achieve that though yes?

Having seen that an alumised exhaust is only £55 I am tempted to just do that. Maniflow would be nice but it is dear
bmcecosse
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Re: New Exhaust Query

Post by bmcecosse »

I would just stick with the aluminised exhaust - when I 'upgraded' mine I noticed very little difference. However a better/no hot-spot inlet IS worth having.
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