Big bore exhaust

[Martlin]

Having fitted an Ital 1275 motor I now want to upgrade the exhaust system.
I have a Modified Metro manifold (I have cut off the intake part) and bought a ESM big bore exhaust system.
My question is,what fittings starting from the manifold end willI require to fit this exhaust?
Many thanks,
Martin.

[panky]

The first thing to check is to make sure the manifold outlet matches the 'bell' on the down pipe. I used a similar manifold and found that it was smaller than the sports system, I cut the welded adapter off and re-shaped the end of the pipe to fit the manifold. From there a brace from the down pipe to the engine or gearbox is essential to keep everything in place.

This is my set up after I changed to a Miget manifold



The clamp has since been changed to a cast version.

This is the middle hanger that attaches to the floor under the rear seat.



There is another further back to support the back box but I haven't got a picture of that one.
Hope this helps.

[IslipMinor]

Which engine is the system designed to fit?

It looks like you will need to rejig the beginning part of the pipework to get it to fit the exhaust manifold - once that is done the system will (definitely should) fit using the standard mounts. Make sure that you use the mount that fits before the swan neck over the axle, and the one at the very back of the system.

As has already been said, the matching of the 'bell end' to the manifold is critical - does it match? Next is to get a really good strong clamp, as in the picture, to make sure that you get a good seal to the system.

Assuming that the engine is in the car, I would fit the exhaust manifold, and then fit the exhaust system with the sawn neck central fore and aft over the rear axle as starting point. What does the alignment (more likely lack of) between the manifold and the front of the exhaust system look like look like? Can you post some pictures?

You should get a nice sounding burble from the system, very pleasant to accompany you on trips.

The engine moves around quite bit (quite normal!), so I would be careful about trying the restrain the front end of the system too much. The manifold is quite capable of supporting the front half of the system, without needing any additional mounts.

We have a 2" OD system, with 3 straight-through silencers to keep the noise to an acceptable limit for track days, and that is supported in the middle and at the back, I have replaced the mounts maybe twice (as a precaution) in nearly 20 years and 60,000+ miles.

The tricky part will be getting the front to mate with the manifold. If you are anywhere near Oxford and can get the car and system to us, I am very happy to help with the front fitting - MIG welder just waiting to burst into action!

[philthehill]

Looking at Panky's exhaust manifold it appears to be a MG Midget/Sprite manifold which has the manifold outlet facing forward.

Martin
Your manifold Pt No: 12G3538 will exit in the right direction and if the front pipe has been formed correctly will join together with the manifold without any difficulty. The cast manifold clamp from ESM is a must and is pictured on page 41 of the latest Minor Matters.

[paul 300358]

I used one of these, https://www.ebay.co.uk/itm/Classic-Mini ... Sw3xJVcXgi Make sure that you fit it the right way round, one side has a slightly larger diameter hole. I can't remember which way round they go.

[panky]

Looking at Panky's exhaust manifold it appears to be a MG Midget/Sprite manifold which has the manifold outlet facing forward.

Martin
Your manifold Pt No: 12G3538 will exit in the right direction and if the front pipe has been formed correctly will join together with the manifold without any difficulty. The cast manifold clamp from ESM is a must and is pictured on page 41 of the latest Minor Matters.

The final incarnation is indeed a Midget manifold but I initially used a manifold from a Mini 1100 with the sports exhaust (which looks very similar to the one the OP is using). With that set up I modified the end of the down pipe to suit but eventually welded on a flare from a pipe I had on the shelf to mate with the Midget item.

[Martlin]

Once again,many thanks to all for the excellent advice and offers of help.
What a great club we all have!

[Martlin]

May be of interest if you are fitting a big bore exhaust.
IslipMinor was quite right that I may have difficulty in fitting this system!
What a pain!
First thing to fit was the front downpipe,yes when mated up with the Metro manifold
It hit the underside of the passenger floor!,so I cut a “v” in the top of the pipe just as it passed through the bulkhead and welded in a couple of plates.So far so good,but wait a minute,when the second section was offered up the Silencer fouled the centre crossmember.Right so I cut 2” off the downpipe now the Silencer is clear of the crossbeam,great! But hang on,the swan neck now fouls the back of the rear axle!I know,I will weld the 2” I had previously cut from the front pipe to extend the middle section to fit correctly over the rear axle.Happy days! Not quite as the pipe that exits the rear of the car is not quite at the right angle.a bit more cutting and welding I should be there!
Or is it just me?
Martin.

A5177F30-AB26-4D2D-A8B9-EC79D89CD497.jpeg (692.4 KiB) Viewed 1770 times

2AFE2550-67EF-4FF8-8FC4-BBA7F6453970.jpeg (959.93 KiB) Viewed 1770 times

0EF98458-3543-4144-ACFF-4721846F9049.jpeg (883.6 KiB) Viewed 1770 times

[jagnut66]

Hi,
I spent ages trying to get a larger bore exhaust system, supplied by one of the main suppliers, to match up with first a Marina and then a Midget manifold for Abby, to mate to the 1275 Midget engine I installed when I owned her.
The lesson I took away from that is, where possible, buy the matching manifold for the system you're buying.
I have bought a Maniflow system for Sally and, this time, I forked out a little extra and included their inlet and exhaust Manifolds.
I'm hoping to save myself allot of grief in the long run...........
Best wishes,
Mike.