Stainless steel exhausts

[R there other M reg P5B coupes]

Anybody got any experience of good stainless steel exhausts for a P5B which still sound like the mild steel versions and more importantly have the twin tail pipes of the correct diameter and angles ?

[johnwp5bcoupe]

I think you are on a mission to nowhere as far as the sound is concerned I had mine made completely from T304 of the thickest grade they could bend it's not bad but still not the same note as a Mild Steel one SS will always resonate

[Phil Nottingham]

It spends on which system you buy some are more noisier than others it depends on the grade of SS and design - however modern fabricated mild steel replacements last nowhere near as long as Rover and later Burgess boxes and as they are 2/3rds the price of stainless its cheaper in tey long run to convert.

Its the back box that is the noisier - eventually they all get louder as the wadding get blown out


I use Goughs who also fit them which is well worth the small cost as they will fettle them to fit properly. They look like the OE although they do use mild steel on some of the flanges
Again well covered in the past so try SEARCH

Quite a lot of owners do not realise how quiet a P5B should be - the burble is very supressed at low revs and non-existent at speed/acceleration

[johnwp5bcoupe]

I find the most anoying part of the system is the down pipes etc to the first box Phil the boxes arent too bad they are well made I wonder if I had had the lower grade T409 which is a lot softer instead of the T304 what the difference would be apart from the T409 going a grotty dull colour

[theroveringmember]

Though who can complain at the sound of a burbling V8.
I'm still running on mild steel but have a stainless silencer on our 110 & do notice the sound difference compared to other moving P4's I've heard at rallies.

[Phil Nottingham]

P4's SS exhausts are very much louder than teh mild steel and sound terrible. My 3 Litres SS is just as quiet though!!

Cheaper/thinner SS makes a tinking noise as well especially in front pipes. Decent ones are rreally quite heavy

[johnwp5bcoupe]

What are you trying to say Phil my front pipes are 16swg any more than that and you have a problem bending the tube plus cracking as T304 is very hard and far from cheap

[Phil Nottingham]

Some SS front pipes are much thinner than 16g - they look to be less than 20g

[johnwp5bcoupe]

I will let you get away with that one

I had thought about wrapping the front pipes in the same stuff they used on racing engines like an Asbestos bandage ;)of course it wont be made of that now

[Warwick (Ozcoupe)]

Why did copper exhausts dissappear? I have a vague recollection that they were banned down here from about the late '60s or early '70s, although I don't know why. (Could be imagining it of course). I had a mate with an MGB with a copper exhaust, and it sounded fantastic.

[dorsetflyer]

If you had a copper exhaust now it would be worth more than the car itself the way scrap prices have gone through the roof.

[johnwp5bcoupe]

It's about 3K a ton

[Warwick (Ozcoupe)]

Yes; it's about the same here - $7k. Because it's so soft, perhaps it removes all resonance. I just remember that it made a 4-cyl BMC engine sounds really good.
I have a lot of copper tube in the shed up to 2". A good thing my address listing is a bit vague.

[Phil Nottingham]

Copper does sound a good idea from a sound deadening view point but not sure how well it would perform at the stress point at the Y branch and the joint to the single pipe. Copper work hardens very quickly and I think it would soon fracture?

[Warwick (Ozcoupe)]

I think it was only used for single pipes. i.e. from the engine pipe (down pipe?) back. I only ever remember it on sports cars and Minis.

[enigmas]

Where were you in the 60's Warwick? A good number of of the guys I grew up with had older brothers with Ford Customlines, Zephyrs and hotted up FJ, FB Holdens and the like, which all seemed to run twin 2" copper pipes attached just after the manifolds and mostly under-slung the rest of the way. It was the cool thing to do. I can recall a ride in a big "cusso" with the driver a young builder with his bare foot pressed hard to the metal (on a foot shaped accelerator pedal) cresting the hill on Burwood road (near Bennettswood just before Middleborough Rd) with the big 292 ci Y block howling as he changed into 3rd gear at something just over 90 mph. Now that's a memory!

[Phil Nottingham]

The Mini down-pipe in mild steel fractures easily enough under normal engine movement!

[Warwick (Ozcoupe)]

May 21, 2008 13:02:28 GMT enigmas said:

.... with his bare foot pressed hard to the metal (on a foot shaped accelerator pedal) cresting the hill on Burwood road (near Bennettswood just before Middleborough Rd) with the big 292 ci Y block howling as he changed into 3rd gear at something just over 90 mph.

Yeah; I remember it flashing past. My aunt lived just near there. I didn't realize he wasn't wearing shoes.


Plenty of mates with FJs, FEs and FCs Vince, but the only cars I remember with copper pipes were BMC fours.
Do you remember why they were banned? Were they in fact banned? Was it perhaps the work-hardening issue and possible cracking and admission of fumes into the car? Was it ground-clearance issues because they were under-slung?

[enigmas]

Warwick, my father had a Citroen ID 19 in the early 70's and it had a copper exhaust pipe fitted from the back of the muffler which was mounted up front just behind the engine. This was a long straight length as the floor was flat from front to rear. The car used to have a lovely burbling exhaust. I know it was non standard as I was apprenticed at the time to PJ Reagan Motors, importers of Peugeots & Citroens.
As for what happened to copper exhausts, I think the material just got too expensive. Most of the guys running copper exhausts were tradies and there would always be the odd spare piece of copper on the job site. ~ Vince

[Warwick (Ozcoupe)]

It would be nice and easy on an ID or DS as you say Vince. Just a long straight pipe hanging under the floor. But I do have a definite recollection that it was banned. I must do some checking - I hate annoying mysteries (even trivial ones).
My father always wanted a DS or ID but ended up replacing the FJ (I got it when I got my licence in '68) with a 404. Prior to getting it we had a few trips to Regans. I ended up replacing the FJ in '76 with a 404 from Frank Mardling on the Nepean Hwy in Cheltenham. I used to drive a Preston Motors (Dandenong) Holden parts delivery van in the summer holidays in the late '60s and early '70s and whenever I was down around Cheltenham I'd stop and drool over the DSs in a small Citroen yard on the highway. I forget the company name. (Sorry - getting a bit off topic here. There will be people having small seizures at the mention of French cars although I notice Admin giving them a free plug).

Back on track - I have enough large bore copper tube at home to try it out on the Rover one day to see what it sounds like. I've often thought it would be interesting to have 2 rear mufflers with a by-pass butterfly under the floor. One with a sporty note and one totally silenced. But then that's all dreaming isn't it; by he who still hasn't got the SUs back on the car.

Better finish by mentioning stainless steel.