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Original TR2 exhaust size and position


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Hi.

 

I need a new exhaust.

I have a SS downpipe from Moss, but I will have a local muffler and and pipe made as its less than half the price because of exchange rate and import duties..

But I am struggling to get a few sizes and positions straight.

 

As far as I know, the 1955 muffler is 24" in length, but measuring a box today that seems too long in that it will touch the diff especially since the new boxes are wider and have to be mounted slightly further back to not touch the chassis at the cross. I'll opt for a 500mm one (so about 20") as a good compromise.

On some forum I found a width/height of 5" X 3" where the boxes I can find here seem to be larger at about 7" X 4" which is not helping the fit at all. It looks like I could get closest with about 6" X 3.5".

 

So the question is. Does anyone have an original muffler to measure exactly?

Also does anyone have an undercar photo of positioning? Both original and a modern (if the modern is a different size) would be great.

I will go original, so only a single muffler and not the 2-box TR3 system.

Then I need pointers as to adjustment on the larger muffler. I read that it may require mounting at a slight angle?

 

I would also like to see a photo of the brackets at the cross, diff and back. I seem to not have one at the diff and the diagrams on the parts sites show one. But I can't find a photo showing exactly where/how that bracket is attached.

I can ask the people to make a custom one temporarily while I order the correct brackets from Moss, but I still need to see where it needs to be attached.

 

Lastly, am I correct that the system is connected with brackets and not welding? Wouldn't this need constant re-adjustment?

 

Can anyone provide such photos and information?

 

Dirk

 

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Hi Dirk ~

 

The original TR2 silencers were 18" long and had a great sound! I've fitted a new SS system to my 3A but with only one silencer.

I'm hoping to reproduce that wonderful roar of the TR2's.

Here is a photo. of the underside of my 3A.

 

Tom.

Edited by Fireman049
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Thanks Tom!

 

That picture already shows a lot!

So from that and an underside I saw from MVC575, it seems like there is a bracket holding the exhaust only at the front of the crossing and at the rear, not in between..

Your box looks much smaller than what I saw today. Is it an 18" one? The width looks at least 1.5" less than what I saw today at the dealer.

 

Dirk

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Peter Taylor's excellent drawings in the Moss Europe catalogue clearly shews the 4 designs of centre exhaust mount, at the cruciform of the chassis under the gearbox mount. These he produced from real items and a view of cars in the C&B workshop at Grena Road.

 

Many of us have gone for the TR4 set up that clamps the pipe joint with a clamp (130890) to a right angled bracket (130888) that is attached to the gearbox mounting bolt. In that set up the entire exhaust is attached to the power unit, and swings with it. The issue that comes about is that the hole through which the exhaust passes in the chassis requires the pipe to got through at the correct height and angle - or it clouts, loudly, especially if your gearbox mount is shagged. Using the early original arrangements too often ended up with the pipe joint loose and leaking - I now always double clamp the pipe joints at this connection.

 

https://www.moss-europe.co.uk/shop-by-model/triumph/tr2-4a/exhaust/exhaust-systems/exhaust-system-fittings-tr2-4.html

 

In parenthesis - for years the front box (middle section) of the exhaust system was made with the wrong bend/set at the front, and an incorrect angle that the pipe entered the silencer box - all due to repro copies of copies of copies..... The stainless steel exhaust manufacturers seem hell bent on creating bigger oval size silencers than the original, this means the clearance of the silencer to the chassis rail just as it exits the cruciform is reduced, and whacks it. In truth the best system to stop 'exhaust to chassis impingement' is/was the the SAH/TT 5001 straight pipe through the chassis with a single silencer behind the axle line. This places the silencer more or less where it ought to be in the system. Plus for there is a stainless version available. - I once found the stainless ones lost all their stuffing inside of 3 months use. The mild steel, originally rusted quickly externally and needed painting prior to fitment. Although the chrome tailpipe always stayed perfect.

https://www.moss-europe.co.uk/catalogsearch/result/?search_group=&q=TT5001

 

This is not a recommendation - just an observation from a one time user.

 

We did once make our own single box system with a TT5001 link pipe and a Stateside Cherry bomb then tail pipe - now that was noisey. https://www.demon-tweeks.co.uk/performance/universal-exhaust-silencers/custom-chrome-racing-stainless-steel-cherry-bomb-silencer

 

Peter W

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I realise that this isn’t the standard arrangement seen on the sidescreen cars, but it might be of interest.

 

My TR4 has a 4-branch exhaust which brings 4 into 2 pipes, these ending beneath the starter motor. Here, the 2 pipes enter a short stainless Y-piece, which connects to a serpentine stainless pipe running to a point beneath the rear of the gearbox. At this point there is the bracket 130888 and clamp 130890 in front of the central chassis box, through which the exhaust must pass. Then there’s a stainless pipe which has a slight bend and which runs to a point just forward of the rear axle, where it feeds into a stainless silencer box which is circular, 24” long and 3½” in diameter. There is no separate tail pipe as the silencer box protrudes clear of the rear valance.

To support this arrangement, there is a bracket welded to the inside vertical wall of the chassis, forward of the axle, and from this I have a fabric hanger to support the clamp which joins the tube and silencer.

At the rear, a fabric hanger secures the silencer box’s exit tube to the rearmost cross tube on the chassis.

This all makes for a very secure system, and the exhaust does not hit the chassis in the central box area.

 

It would not be difficult to make an L-shaped bracket to support the arrangement forward of the axle, and either weld or screw it to the chassis – I suspect that mine was welded in position by the Competitions Dept in 1962, as one doesn’t want the exhaust falling off in a rally!

 

In assembling the exhaust, I always coat the joints of the pipes with Copaslip, as it makes dismantling later so much easier.

 

After many years of use, the stainless silencer box developed a crack at the front end where the tube enters the box. I found someone who could weld stainless steel and he put 4 bracing strips at both front and rear end of the box – an extremely strong repair!

 

Ian Cornish

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@ Peter W.

 

Thanks for the info Peter.

I do have a question about the Moss drawings which is still quite confusing to me.

On the bottom right the brackets with numbers 40-50 seems to indicate it fits just behind the front muffler.

There is no mount point for such a bracket I can see on my car. This would have to be right at the rear axle. Just in front or behind.

Photos I found of restored TR2 systems show no bracket in that position I can see. Perhaps it is specific to TR3A?

This is MVC575

https://www.moss-europe.co.uk/media/wysiwyg/73.MVC575-06.10.16.jpg

 

I found and old post on another forum, by Don Elliot I think, where he stated he made his pipe slightly oval where it passed through the cruciform, which helped a lot.

 

Dirk

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@ Peter W.

 

Thanks for the info Peter.

I do have a question about the Moss drawings which is still quite confusing to me.

On the bottom right the brackets with numbers 40-50 seems to indicate it fits just behind the front muffler.

There is no mount point for such a bracket I can see on my car. This would have to be right at the rear axle. Just in front or behind.

Photos I found of restored TR2 systems show no bracket in that position I can see. Perhaps it is specific to TR3A?

This is MVC575

https://www.moss-europe.co.uk/media/wysiwyg/73.MVC575-06.10.16.jpg

 

I found and old post on another forum, by Don Elliot I think, where he stated he made his pipe slightly oval where it passed through the cruciform, which helped a lot.

 

Dirk

You are confusing the TR4 mountings with sidescreen car ones, look on the right hand side of the listings as it references the models there.

Stuart.

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Ah stupid me.

Ok all settled then, thank you for the input!

I have decided to stick with a 20" as compromise for now as the 24" seems too long to fit properly with incorrect width.

The hardest part seems to be to find one with width < 7.5" and height < 5" at the moment.

I found a post somewhere that stated even the Revington? one is roughly 21" X 6.5" X 4".

 

Dirk

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My 3A had problems for years until I welded the front mounting bracket for the third time because it fitted on top of the gearbox mounting but kept snapping. Finally it was OK.

 

It is very close to the cruciform but never hits it.

 

I had a front box made to fit because I wanted to use the car for touring and find the "sports car" noise tiring. I do still enjoy the underpass. Sorry fireman :) But the new box used to hit the floor on rare occasions. This went on until I had an Australian welder working for me on some very complicated RSJ problems. One afternoon I took the silencer to the site and in no time he chopped 6" off the top of the box and welded it back up. It has been OK for over 10 years now. I also modified a VW exhaust hanger with two flexible hooks which help hold the big box but was not much use.

 

However the problem that I still have is that it is possible to move the silencer back by reversing over the grassy bank and then setting off again. It just needs pushing back in and tighten the clamps AGAIN.

 

Good luck Richard and H.

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My current very bent and rusted setup seems to have a 16" silencer behind the rear axle.

It seems this setup makes the fitting much easier.

It has a very good exhaust note (or had until it developed a leak just below the manifold).

Its not terribly loud to my ears and the sporty note is very fun. Especially from 2400-3500 rpm.

I just felt, since I am returning everything to as close original as possible seeing that the car is 95% there anyway, I should do the same with the exhaust.

I think though if the guys can't make the proper size, I'd perhaps shop around a bit more and temporarily plug the hole to get the car through roadworthy.

They are not as stringent here as in the UK, so a temporary plug will go unnoticed.

 

Thanks Richard.

The exhaust guy also explained that the section clamps are likely to constantly loosen and welding is recommended. The exhaust hanging clamps seem to be a mix of standard and cheap but servicable mods by the PO.

I'll probably do the sensible thing as everyone recommends and go TR4 mount in front but standard at the back.

I am certain I'll be able to get someone to modify the box size wise. After all the straight through is very simple. I am sure a competent person can open up the box and resize to spec without too much effort.

 

Dirk

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Hi Dirk ~

 

My silencer is the longer of the two silencer system and it's not the 18" one.

I'm tempted to replace my silencer with the shorter (rear) silencer but fitted in the same position as this one.

 

Tom.

Hi again Tom, I have recently fitted a complete ss system to Poppy what a job and even now it touches where it fits. I did think the same as you about just fitting the larger box but The only reason I changed mine was it was cobbled together and really noisy. Have you run yours with the set up in the photo yet? Cheers Chris

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