Exhaust system

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Remyd
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Exhaust system

Post by Remyd »

I am going to have to change the exhaust system in the near future and since I am a novice at this kind of things I was after some advice on which exhaust to buy.
Ideally stainless steel to fit a three branch manifold and looking at a cherry bomb to have as much ground clearance as possible .
I know that I need new fittings as well but is there anything else I would have to buy to fit it to the car?

Thanks in advance!
Remy Dubois
1971 MGB GT
Vic Butler
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Re: Exhaust system

Post by Vic Butler »

Is the manifold the original MG cast iron one? If it is, be careful when attempting to undo the down pipe nuts as the studs are likely to break. Get new studs and brass barrel nuts. These nuts cover the studs completely so they can't rust. Downpipe studs for Series 3 Land Rovers are the same if you can't get MG ones
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
Ian F
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Re: Exhaust system

Post by Ian F »

Remy,
depends to a degree what you are doing with the car. I would suggest:

Get stainless, not much more expensive and saves a lot of future work.

Get a small middle box, gives much needed extra ground clearance.

Think carefully about a noisy "sport" exhaust. Can be quite tiring on longer motorway journeys. The MGB GT is noisy enough!!

Ian F
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1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear
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Remyd
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Re: Exhaust system

Post by Remyd »

Thanks,

Only driving the car around and such, not racing. definitely stainless steel and smaller middle box as mine scrapes the road bumps already.
Any other things I would need apart from fixing kit? I don't think that the exhaust is original as it was changed about 7 years ago according to the history and invoices I got from a previous owner
Remy Dubois
1971 MGB GT
Ian F
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Re: Exhaust system

Post by Ian F »

Get some assembly paste to make putting it together more easily and to ensure a seal. You may need some new studs and nuts, but you would have to check what you have fitted. Getting all the correct clearances can be a task so the other thing you need is patience ( can't be bought at Halfords.........)

Ian F
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1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear
lightning
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Re: Exhaust system

Post by lightning »

Hi Folks,
I had much trouble with "sleeping policeman" and such so I change the exhaust to a large bore with only one silencer at the rear (by the fuel tank) eliminating the first silencer and providing more ground clearance, less joints too. Although it is a sports system it does not seem too noisy, just a pleasant burble, quite comforting on a lonely night drive. ATB Brian
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Re: Exhaust system

Post by Vic Butler »

That's what I've fitted. It's a 2" bore single rear box stainless steel system with matching tubular exhaust manifold. It's not too noisy, just a pleasant sound like Brian's.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
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Tom Brearley
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Re: Exhaust system

Post by Tom Brearley »

I've got a bomb centre box but improved the ground clearance further by modifying the middle hanger. As shown in the pic, I've moved the fixing holes closer together which raises the exhaust up.

Clearance is now about 5 inches in the middle, which means speed humps pass harmlessly beneath. This set up has been fine over the last 6000 miles.
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1973 MGB GT
Mallard Green / Autumn Leaf
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