14 replies to this topic

[MikeMPi1999]

I have 1999 in the middle of a restoration. Engine has just been finished (below) and im shopping for exausts.

 

My head is spinning with all the options when it comes to exaust pipes. Here are just some of my questions.

 

- Is stainless an option? I see Moss sell an RC50 in stainless but only for carb engines?

https://www.moss-eur...st-systems.html

 

- Manifolds - Lots of people talking about Maniflow, what do I need to know? 

 

- LCB? (long center branch) What does this mean?

 

- I wont be fitting the cat back on, how does this effect things?

 

My target is to have a modest set up, not particularly loud or drony, just somthing with a bit of fizz and personality to it that doesnt break the bank. Where do I start? Thanks!

Attached Files

•  2023-09-30 16.10.36.jpg   95.21K   2 downloads

[sonscar]

No cat on a 1999 car will be an MOT fail as cat missing.Just saying it should be a fail,Steve..

[Quinlan minor]

I found the Pattern replacement downpipe (MiniSpares GEX12043) hangs too low and grounds at the slightest opportunity, causing leaks and MOT problems. [First pic.}

I changed to the C-AEG371 Downpipes and Link Pipe [Second pic.] which is a much better fit and had no further problems.

 

 

Attached Files

•  Downpipe advisory.JPG   65.77K   6 downloads
•  C-AEG371 Downpipe for Injection (small).jpg   48.92K   6 downloads

[Robanzac]

I have a 1997 MPi

I fitted the following in 2006

Minispares C-AEG371 ..... down pipe and link pipe to cat  (this is mild steel)

Minispares C-STR811  ....  cat back RC-40      (on mine this is SS,  but I am not sure the part # I have given here is)

or you could achieve the same by buying  kit C-STN22

 

The above stuff all fits very well, and doesn't hang low below the car.

 

I would have to say this has been one of the most pleasing exhaust modifications I have ever done to a car.  It is a hard thing to get right.

It is quite deep and subtle, doesn't rasp, doesn't drone,  and I wouldn't call it loud.

It still pleases me to this day even after 17 years.

What didn't work was removing the cat.

I tried this briefly with a straight pipe in place of the cat. This lasted about 10 minutes. It was too noisy and droned,  even at town speeds.

I also seem to recall reading at the time that the cat fitted to these cars is way oversized for the job, so losses from keeping it are negligible.

If you delete the cat I think you will need a second small muffler in there to civilize it again. Might as well keep the cat if you still have it.

Some photos taken today attached

 

 MPi exhaust 10.23 (1) (Medium).JPG   53.55K   9 downloads

 MPi exhaust 10.23 (2) (Medium).JPG   51.91K   6 downloads

 MPi exhaust 10.23 (3) (Medium).JPG   45.63K   6 downloads

 MPi exhaust 10.23 (4) (Medium).JPG   46.98K   3 downloads

 MPi exhaust 10.23 (5) (Medium).JPG   54.17K   0 downloads

 MPi exhaust 10.23 (6) (Medium).JPG   60.04K   1 downloads

 MPi exhaust 10.23 (7) (Medium).JPG   58.17K   2 downloads

 MPi exhaust 10.23 (8) (Medium).JPG   61.43K   1 downloads

 MPi exhaust 10.23 (9) (Medium).JPG   44.4K   1 downloads

 MPi exhaust 10.23 (10) (Medium).JPG   51.15K   2 downloads

 

[MikeMPi1999]

Awsome information!

[jamesquintin]

I've had my MPI from pretty much new, and I've gone through most exhausts types in that time. For ages I was running an LCB with a stainless RC40, and that was ok. Not too noisy and liveable. I installed the Coopers S kit about 8 years ago, and that came with a Maniflow Twin DTM:

 

 

 

It looks cool, but is VERY noisy. Almost unbearable on motorways. All my friends can hear me coming if I go to their houses.

 

During my restoration I changed from the LCB to the original factory downpipes. My reasoning was I should hopefully get better fuelling as the Lambda is right in the middle of all the exhaust branches (as opposed to jus the centre exhaust ports of an LCB) and also because LCBs just rust away and are hard to seal. I only have one sealing join now and that's at the back of the cat.

I'm also going to ditch the Maniflow and have bought a standard exhaust from Minispares (the £60 one) as I just want peace and quiet 

 

Q
 

[MikeMPi1999]

I've had my MPI from pretty much new, and I've gone through most exhausts types in that time. For ages I was running an LCB with a stainless RC40, and that was ok. Not too noisy and liveable. I installed the Coopers S kit about 8 years ago, and that came with a Maniflow Twin DTM:

 

 

 

It looks cool, but is VERY noisy. Almost unbearable on motorways. All my friends can hear me coming if I go to their houses.

 

During my restoration I changed from the LCB to the original factory downpipes. My reasoning was I should hopefully get better fuelling as the Lambda is right in the middle of all the exhaust branches (as opposed to jus the centre exhaust ports of an LCB) and also because LCBs just rust away and are hard to seal. I only have one sealing join now and that's at the back of the cat.

I'm also going to ditch the Maniflow and have bought a standard exhaust from Minispares (the £60 one) as I just want peace and quiet 

 

Q
 

 

Can you pop a link down below to the LBC you had and another link to the origional? Just so I  can see them, it'll help me picture what you are reffering to regarding the Lambda.

 

Also, im a bit confused, does one maniflow replace the stock exaust manifold and downpipes?

 

Cheers

[MikeMPi1999]

I have a 1997 MPi

I fitted the following in 2006

Minispares C-AEG371 ..... down pipe and link pipe to cat  (this is mild steel)

Minispares C-STR811  ....  cat back RC-40      (on mine this is SS,  but I am not sure the part # I have given here is)

or you could achieve the same by buying  kit C-STN22

 

The above stuff all fits very well, and doesn't hang low below the car.

 

I would have to say this has been one of the most pleasing exhaust modifications I have ever done to a car.  It is a hard thing to get right.

It is quite deep and subtle, doesn't rasp, doesn't drone,  and I wouldn't call it loud.

It still pleases me to this day even after 17 years.

What didn't work was removing the cat.

I tried this briefly with a straight pipe in place of the cat. This lasted about 10 minutes. It was too noisy and droned,  even at town speeds.

I also seem to recall reading at the time that the cat fitted to these cars is way oversized for the job, so losses from keeping it are negligible.

If you delete the cat I think you will need a second small muffler in there to civilize it again. Might as well keep the cat if you still have it.

Some photos taken today attached

 

MPi exhaust 10.23 (1) (Medium).JPG

MPi exhaust 10.23 (2) (Medium).JPG

MPi exhaust 10.23 (3) (Medium).JPG

MPi exhaust 10.23 (4) (Medium).JPG

MPi exhaust 10.23 (5) (Medium).JPG

MPi exhaust 10.23 (6) (Medium).JPG

MPi exhaust 10.23 (7) (Medium).JPG

MPi exhaust 10.23 (8) (Medium).JPG

MPi exhaust 10.23 (9) (Medium).JPG

MPi exhaust 10.23 (10) (Medium).JPG

 

Hi Rob

 

Just looking at my system, i seem to have a 2nd muffler after the cat, diffrent to yours. Is yours an MPi?

 

Taa

 

Mike

 

[MikeMPi1999]

Heres an image:

[Quinlan minor]

Replacing the stock exhaust manifold will bring a significant increase in noise within the car. The sort that make high mileage trips tedious in the extreme.
Stock manifold, which means not having to fiddle with/replace the Lambda sensor, the 371, Cat, and an RC40 work well and sound good.

[Robanzac]

Yes, mine is an MPi  (twin point injection)

The photo of your existing system look pretty much like that shown in the Rave manual  (Mini Workshop Manual 5th Edition),  and pretty much what I remember removing (it is a while ago now)

 

I should also emphasize that I did retain the original cast manifold. 

As Quinlan says above,  aftermarket tubular extractors often increase the racket significantly,  can be quite snarly and not at all pleasant.

Wrapping them in exhaust wrap can tone them down,  but then they eventually crack from heat stress.

 

Do you know what your existing system sounds like ?

If not, I would just install it and work from there.  It gives you a base point.   Mucking about with  exhausts post restoration is no big deal.

You might actually like it the way it is.

You could even experiment  with it fairly cheaply and reversibly

Replace the cat with a straight piece.

or

Replace that 1st muffler after the cat with a straight piece  (flange it all so you can put it back if need be)

 

(update added 20 mins. later - I should also add that a muffler right at the back is generally a good thing, systems with lots of pipe after the last muffler tend to bark a bit)

 

Screen captures from Rave below showing the factory MPi system from head back

 MPi exhaust from RAVE 1.PNG   27.02K   3 downloads

 MPi exhaust from RAVE 2.PNG   38.29K   3 downloads

Edited by Robanzac, 19 October 2023 - 09:18 PM.

[MikeMPi1999]

Replacing the stock exhaust manifold will bring a significant increase in noise within the car. The sort that make high mileage trips tedious in the extreme.
Stock manifold, which means not having to fiddle with/replace the Lambda sensor, the 371, Cat, and an RC40 work well and sound good.

 

Great thank you.

 

And no mention of stainless steel in this thread?

[MikeMPi1999]

Yes, mine is an MPi  (twin point injection)

The photo of your existing system look pretty much like that shown in the Rave manual  (Mini Workshop Manual 5th Edition),  and pretty much what I remember removing (it is a while ago now)

 

I should also emphasize that I did retain the original cast manifold. 

As Quinlan says above,  aftermarket tubular extractors often increase the racket significantly,  can be quite snarly and not at all pleasant.

Wrapping them in exhaust wrap can tone them down,  but then they eventually crack from heat stress.

 

Do you know what your existing system sounds like ?

If not, I would just install it and work from there.  It gives you a base point.   Mucking about with  exhausts post restoration is no big deal.

You might actually like it the way it is.

You could even experiment  with it fairly cheaply and reversibly

Replace the cat with a straight piece.

or

Replace that 1st muffler after the cat with a straight piece  (flange it all so you can put it back if need be)

 

(update added 20 mins. later - I should also add that a muffler right at the back is generally a good thing, systems with lots of pipe after the last muffler tend to bark a bit)

 

Screen captures from Rave below showing the factory MPi system from head back

MPi exhaust from RAVE 1.PNG

MPi exhaust from RAVE 2.PNG

 

 

Yes, I ran the car for a few years, the exaust note never really made an impact. Induction noise was usually what I picked up on.

[MikeMPi1999]

Replacing the stock exhaust manifold will bring a significant increase in noise within the car. The sort that make high mileage trips tedious in the extreme.
Stock manifold, which means not having to fiddle with/replace the Lambda sensor, the 371, Cat, and an RC40 work well and sound good.

 

Sorry, one other thing. The 371, looks exactly like what I currently have - is there any advantage togetting this over putting the origional back on, cat and RC40?

[Quinlan minor]

 

Replacing the stock exhaust manifold will bring a significant increase in noise within the car. The sort that make high mileage trips tedious in the extreme.
Stock manifold, which means not having to fiddle with/replace the Lambda sensor, the 371, Cat, and an RC40 work well and sound good.

 

Sorry, one other thing. The 371, looks exactly like what I currently have - is there any advantage togetting this over putting the origional back on, cat and RC40?

 

Providing your original doesn't hang too low (as per post #3, above) then, by all means re-use it, with new gaskets, obviously.

I found the GEX12043 downpipes got scraped by speed humps/ steep drives/etc., until they leaked (potential MOT failure), within a short time.