Volvo Amazon Exhaust system

[Classic rally]

Hi

I have a 1968 123GT and am trying to get a decent exhaust sound from it. It has a new simons exhaust system on it which sounds of nothing. I removed the back box which did increase the sound but it is not a nice sound. I heard that the long silencer on the simons exhaust dampens down the sound a lot.
It looks like it has stock exhaust manifold on it.

Could someone who has experience please advice. Is there a better system that produces a nice sound on acceleration that will note drone? I could not find much for the amazon.

Is it a question of having a custom system made and if so could you advice a place. I have had bad experiences with other cars where they have made an awful system.

Thanks

[Rustinmotion]

Originally Posted by Classic rally

Hi

I have a 1968 123GT and am trying to get a decent exhaust sound from it. It has a new simons exhaust system on it which sounds of nothing. I removed the back box which did increase the sound but it is not a nice sound. I heard that the long silencer on the simons exhaust dampens down the sound a lot.
It looks like it has stock exhaust manifold on it.

Could someone who has experience please advice. Is there a better system that produces a nice sound on acceleration that will note drone? I could not find much for the amazon.

Is it a question of having a custom system made and if so could you advice a place. I have had bad experiences with other cars where they have made an awful system.

Thanks

I removed the long Simons middle silencer as it droned and replaced it with a short oval jetex box part number U355124 and made the difference up with a length of 2” exhaust pipe my set up is 4 branch 315mm centre box and the rear Simon’s silencer and I’m happy there is no drone it has a nice but not too loud sound people have asked what’s under the hood

[Classic rally]

Originally Posted by Rustinmotion

I removed the long Simons middle silencer as it droned and replaced it with a short oval jetex box part number U355124 and made the difference up with a length of 2” exhaust pipe my set up is 4 branch 315mm centre box and the rear Simon’s silencer and I’m happy there is no drone it has a nice but not too loud sound people have asked what’s under the hood

Thanks. I hadn't thought about leaving the rear silencer in. I think I will remove the long middle silencer as you did and out in a straight pipe in that section and just leave the rear Simons muffler and see what it sounds like. If its too load or unpleasant Ill put in another silencer in the middle as you have done.

Thanks for the help

[313jg]

I have used Simons exhausts for years. I have found that the sound can vary from one system to another.
Deletion of the centre resonator box does not make that much difference to the sound and have not experienced droning myself doing this. In fact one of my Amazons is louder with the centre section than the one without!
Looking at your user name I ask whether or not you use or plan to use your car in classic rallying? If so you do not want to fall fowl of the noise restrictions under the MSA event regulations by having too loud a sound and then being prohibited from competing.
My rally Amazon has a straight centre pipe and specialist made rear section/silencer. The benefit of this is that it can be made to fit much tighter to the body and stronger if it gets hit on unmade roads.

[northNH]

Abarth, the gold standard from the sixties…
New, with 2” inlet.
For Sale, expensive.

[Classic rally]

Originally Posted by 313jg

I have used Simons exhausts for years. I have found that the sound can vary from one system to another.
Deletion of the centre resonator box does not make that much difference to the sound and have not experienced droning myself doing this. In fact one of my Amazons is louder with the centre section than the one without!
Looking at your user name I ask whether or not you use or plan to use your car in classic rallying? If so you do not want to fall fowl of the noise restrictions under the MSA event regulations by having too loud a sound and then being prohibited from competing.
My rally Amazon has a straight centre pipe and specialist made rear section/silencer. The benefit of this is that it can be made to fit much tighter to the body and stronger if it gets hit on unmade roads.

I removed the middle resonator and put in a straight pipe and as you have said has not made much difference. Slightly loader but not a nice sound. Who made your rear muffler? I am trying to se if there is an off the shelf muffler that could work in the rear. I am not sure weather to use a cherry bomb rear muffler or a chambered muffler like the flowmaster as I would like to get a decent sound out of it.

I wonder what system the Targa Tasmania Amazon has. https://www.youtube.com/watch?v=-YNATT9J0Nw&t=232s
This sounds nice. I appreciate the engine must be tuned but if I could mimic this exhaust it should sound good.

I am not looking to rally the car professionally but am very interested in the Hero events and similar.

[313jg]

Both Hero/ERA and HRCR events have noise limits. These are usually much quieter than stage rally limits.
If you go onto the technical pages of these sites the noise limits are usually detailed.
Before you go spending lots of cash can you measure your current noise limits? With your current rear box and the middle expansion box removed.
You can get a free app for a noise meter or pay for a more expensive one which will give you a reasonable guide as to the present noise levels. If the current reading is around the limits on the above sites you will be wasting money purchasing something that's louder than allowed and negating your ability to enter one of the events.
Hero/ERA said to me that normally any car set up to HRCR (Historic Rally Car Register) regulations will be able to comply with Hero regulations.
Hope that is of help.
Don't waste money for the sake of a tune!!
The business here that did my exhaust is too far away from you to be much assistance.

[Natedog]

I’ve got a 2 inch power flow on my Amazon, and when it’s running it’s got a really dense burble, brilliant exhaust that’s I’ve kept since doing a resto on the car. Motor is over 2ltr twin carb

[DOGSTAR]

Hi,
I recently had my inlet/outlet manifold recoated by Zirotech, but was not happy with the finish as the manifold was quite pitted, so i decided to open up a can of worms and upgrade my single zenith carb to the twin SU's but wanted a custom inlet/outlet manifold. Haywood and scott made one for me, but suggested i upgrade the exsisting stainless pipe as it was only 1.5 inch and the manifold was 2 inch, which i did, sounds great and increased my hp by 20!

Originally Posted by Classic rally

Hi

I have a 1968 123GT and am trying to get a decent exhaust sound from it. It has a new simons exhaust system on it which sounds of nothing. I removed the back box which did increase the sound but it is not a nice sound. I heard that the long silencer on the simons exhaust dampens down the sound a lot.
It looks like it has stock exhaust manifold on it.

Could someone who has experience please advice. Is there a better system that produces a nice sound on acceleration that will note drone? I could not find much for the amazon.

Is it a question of having a custom system made and if so could you advice a place. I have had bad experiences with other cars where they have made an awful system.

Thanks

[Classic rally]

Originally Posted by DOGSTAR

Hi,
I recently had my inlet/outlet manifold recoated by Zirotech, but was not happy with the finish as the manifold was quite pitted, so i decided to open up a can of worms and upgrade my single zenith carb to the twin SU's but wanted a custom inlet/outlet manifold. Haywood and scott made one for me, but suggested i upgrade the exsisting stainless pipe as it was only 1.5 inch and the manifold was 2 inch, which i did, sounds great and increased my hp by 20!

Hi. Thanks for the info.
How much did they charge for the custom inlet and outlet manifold?
Did they make you a stainless steel exhaust manifold?