S4 Twin exhaust Silencer

[106500]

I'm fettling my exhaust system. Having aquired a stainless twin silencer I'm really struggling to get the exhaust system at a reasonable height off the ground and reasonably close to the chassis. The design of the silencer seems to require a low set connection to the longitudional pipe to the Y piece. I'm wondering if my silencer has been incorrectly manufactured (bought from Paul Matty's) or whether they've given me an incorrect version? Thoughts appreciated....

[reb53]

Despite my best efforts I could never get my "twin pack" at an angle that would prevent it grounding when I backed out of the garage.
Admittedly bit of a slope but got a crunch every time.

It was too noisy to start with, and once the packing had blown out it was embarrassingly anti-social.
I'm too old for that sort of stuff and once I had binned it I could once more put my foot down without every bystander turning around and frowning.

Cheers
Ralph.

[69S4]

I've got a stainless twin pipe on my S4 and not really had much of a problem with ground clearance. I'll try and post a picture of how mine is mounted later as it's easier than the thousand word alternative.

The twin pipe setup is noisy even when new. The 60's roadtests complained about it and if they thought it noisy then ... With the passage of time and the passage of most of the packing out of the back of the box it can be a little too noisy now - particularly when everything is cold. An early morning start doesn't go down well with my elderly neighbours although it does quieten down considerably when it's up to temperature and isn't much different in sound level to my diesel Land Rover.

[69S4]

Attached are a couple of pics of my twin pipe setup.





The mounting bracket at the back has needed a bit of thought to get the silencer tucked in and I'm using a Mini exhaust bobbin. Unfortunately it's in tension (not a good idea) and needs replacing about once a year.

[106500]

Thanks for the replies. I returned the silencer to PM today. It appears that they had a batch of incorrectly manufactured silencers. I've got a better one now. Will fit tomorrow!

[enskr]

Stuart
Do you have problems jacking up the rear of the car with the twin box S4 silencer ?
My S4 has always been awkward to jack with the twin box exhaust running under the backbone. I used to have a very low, very long reach trolley jack onto which I put a piece of 2x2 wood, and jacked it from the sides, in front of the rear wheels - there was just enough room. Unfortunately that jack was recently stolen and the nearest replacement I could get is too deep to get under from the sides so I'm struggling to jack it. How do you do yours?

I've never been a huge fan of the twin box silencer anyway, and I was thinking that a single pipe "sprint" type silencer would make life easier (cheaper than a new jack!).

Kevin

[69S4]

Stuart
Do you have problems jacking up the rear of the car with the twin box S4 silencer ?
My S4 has always been awkward to jack with the twin box exhaust running under the backbone. I used to have a very low, very long reach trolley jack onto which I put a piece of 2x2 wood, and jacked it from the sides, in front of the rear wheels - there was just enough room. Unfortunately that jack was recently stolen and the nearest replacement I could get is too deep to get under from the sides so I'm struggling to jack it. How do you do yours?

I've never been a huge fan of the twin box silencer anyway, and I was thinking that a single pipe "sprint" type silencer would make life easier (cheaper than a new jack!).

Kevin

I've never really managed to work out a satisfactory method of jacking the rear. Even without the pipe in the way I wouldn't be happy jacking under the chassis in the middle as it'll lift both wheels at once and the whole car is then balanced on a single point - a bit like balancing a pencil on it's point, it doesn't take much to knock it over. That's not to say I haven't done it, I'm just not happy doing it.

I used to jack the rear by putting something under the sill to spread the weight - usually a phone book and jacking there but again I don't like doing it and I won't do it now. Mostly I just put the phone book under the front A frame mount (it looks sturdier than the rear one) and jack there, but each time I think that there must be a better way.

All of this is using one of the two trolley jacks I have. The scissors jack that goes in the car usually goes under the rear A frame mount with a paperback book that I keep in the boot to spread the weight ( I can't reach the front mount with a flat). It is useful to keep the jack actually in the car though. I left it out for the first time in ages two weeks ago and guess what - I got a puncture. The two hours I spent at the side of the M25 at Heathrow waiting for the AA to spend 30secs jacking the car up will make sure I don't do that again. Most of that 30 secs was spent stopping the AA man from jacking under the sill.

[Lincoln62]

I have a couple of bits of 8x2 (wood) and have chamfered the ends so they are like little ramps. Roll the car up onto them then the jack fits under fine. That 2 inches makes all the difference.

Pete
66S2

[rgh0]

Attached is a picture of my S4 twin pipe design I made - The local stainless straight through mufflers I could source needed a little "adjustment" to the outer shell to fit in the space.

I use a through bolt for the support with rubber bushes the same as used in the roll bar mount. A bush inside the boot under the bolt and a bush top and bottom of the bracket on the muffler. No risk of the exhaust dropping to the ground as the rubber is all under compression.

i also kink up the 2 exhaust tips rather than have them come striaght out to give adequate clearance which is especially needed when the car comes off its trailer at race meetings.

cheers
Rohan

[69S4]

I use a through bolt for the support with rubber bushes the same as used in the roll bar mount. A bush inside the boot under the bolt and a bush top and bottom of the bracket on the muffler. No risk of the exhaust dropping to the ground as the rubber is all under compression.
cheers
Rohan

That looks like a much better solution and one that doesn't risk the exhaust dropping on the ground when the bobbin lets go. Time to rummage through my spares boxes and see if I can blatantly rip off your idea - with your permission of course.

[fasterbyelan]

I've got a stainless twin pipe on my S4 and not really had much of a problem with ground clearance. I'll try and post a picture of how mine is mounted later as it's easier than the thousand word alternative.

Stuart,

What clearance are you getting between the exhaust and ground, from your photo it does not look to be much more than 4.5"

[69S4]

Hi Karl

Lowest point around that area (the "S" bend that kicks the pipe up into the boxes), with the car unloaded, is 5 1/4". Probably a bit less with me in it (although I am trying to lose weight ).

It was probably nearer 4 1/2" with the previous lotocones. Replacing them has raised the ride height. The bottom of the S bend does have some grounding scars and I kept an exhaust clamp on the pipe there in sacrificial role but post new lotocones it doesn't seem to be grounding any more.

All of this system was on the car when I bought it in the 80's. It's stainless from the Y piece back so almost certainly not the original setup. The mounting bracket on the silencers in particular looks like it was knocked up from Meccano (that's prob original Lotus then ) so fitting has always been a bit of a guess.

[Frank Howard]

The bottom of the S bend does have some grounding scars and I kept an exhaust clamp on the pipe there in sacrificial role...

Stuart,

My clamp was destroyed when I bottomed out 7 years ago however when I removed what was left of it, I added lightness by neglecting to replace it. It has held together without the aid of rust as it is SS. Warning, I am a professional clamp replacer. Do not try this at home.