My Vantage S is now making all the right noises

My Vantage S is now making all the right noises

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V8V Pete

Original Poster:

2,496 posts

125 months

Saturday 23rd September 2017
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This is a story of two very different halves so bear with me if a rather long post. One half is about exhaust noise and the other about unwelcome engine noises.

1. Exhaust.

My Aston is a 2014MY SP10 Vantage S. Being my perfect spec I intend to own it longterm and have modded it to make it as good as it can be for me. I loved the original exhaust note, deep baritone and burbly, but definitely wanted the extra power (and a little more volume) available from a sports exhaust. So in April this year it went to Bamford Rose and got manifolds, 200 cell cats, X-pipe and retained the OEM V8S back box (as there are no real performance gains to be made there, I liked the character of the sound of the back box and wanted to retain the valves so it could be quiet when needed). I went for the X-pipe because I was told that with 200 cell cats and V8S back box it would probably be too loud for what I wanted and the X-pipe would bring this down a bit. It is amazing how much the X-pipe changes the character of the sound. In the top half of the rev range it is all good - a vibrant howl. However in the lower rev range there is loss of bass/baritone character and loss of the characteristic Aston V8 burble which becomes more of a "thrum". Also, I felt the overall exhaust volume was just too loud for what I wanted. This is obviously purely personal and difficult to quantify but it was too much for me most of the time.

BR exhaust V1 with X-pipe:


Various options to improve this exist:
1. Change the back box - but I liked my back box.
2. DAE do a mid-section silencer but I'd heard from an ex-owner that that this makes the car quieter than OEM which I didn't want.
3. Baffled cats. Not confused felines but cats with little silencers immediately downstream. This has been done by BR before for V12 but not for V8.

New V8 baffled cat and standard 200 cell cat for comparison:


Mike and I both thought this would be most likely to give the result I wanted but it was a slightly unknown quantity. Anyway my car went in on Monday, they did the development work and I collected it yesterday. Here are the new pipes in place and the new mid-section with X-pipe removed and small balance pipe reinstated.




Result? Well I think it's perfect. My baritone burble is back. The overall volume is down a bit but not down to OEM. It still has the added character that the 200 cell cats give - enhanced overrun sounds etc. I really am totally chuffed with it and want to say a huge thank you to Mike & Adrian for listening to what I wanted and making it happen. If anyone is in the position I was in or is going for a full exhaust system then I highly recommend this version. Happy to demo it too to anyone that's interested - I'm Midlands based. I would do a video of the sound (start-up, drive-by etc.) but don't have decent recording facilities. Any offers?


2. Unwelcome engine noises.

Seems to have been a bit of this on the forum recently. The V8 is considered to be pretty bullet proof but in my experience has one weakness. My V8S engine was noticed to be very tappety mid last year when still in warranty. My local dealer investigated and didn't really find much and ended up changing the injectors at AML request and this didn't really change anything. So I got an independent report which showed valves clearances were nearly all a bit out and evidence of early cam shaft wear. I therefore went through AML Customer Services and they were happy for it to go for a second opinion at a premier UK dealership. After a stepwise investigation they also found worn valve guides and after having my car for 8 weeks it was eventually returned with a new engine and the problem was obviously resolved.

That would be fine BUT after carefully running the engine in and after only 3000 miles it developed a much more specific valve tappet rattle on the driver's side cylinder bank - WTF?! Simple, I hear you say, just take it back to the dealer and get it sorted. However, I didn't want to be without my P&J for another 2 months and they would squeal about warranty invalidation because of my mods. I could have had BR take the mods off, get the engine fixed at the dealer and then get the mods put back on but the labour to do that would probably have been more than having BR do the repair themselves. So BR replaced the knackered valve tappet bucket shims whilst they had the car this week doing the exhaust. Job done, no messing, car only away for 4 days. Quite why this happened I don't know but I presume either there is a bad batch of bucket shims out there or they were the wrong clearance when the engine was built resulting in massively accelerated wear. Either way it's sorted with no fuss and no endless back and forth from dealer to Gaydon and back.

Now my car sounds perfect back and front and I'm a very happy owner again biggrin

macdeb

8,492 posts

254 months

Saturday 23rd September 2017
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Bugger on the engine front yikes I have a new engine being fitted. I do hope they haven't done a TVR thing and imported suspect parts on the cheap.

bentley01

1,002 posts

135 months

Saturday 23rd September 2017
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Great post Peter and I'm glad it is all sorted. Bamford Rose did a fantastic job on my V8 and I also had the x pipe fitted then taken off. Wish I lived a bit closer too them, it would make having the car looked after simple.

Gettoff

1,434 posts

206 months

Saturday 23rd September 2017
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Glad to hear it's sorted Pete and it's how you want it, let's hope you can enjoy some trouble free miles for the foreseeable.

V8V Pete

Original Poster:

2,496 posts

125 months

Saturday 23rd September 2017
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So I have done a video but only with my phone. No teenagers were involved in the making of this vid - honest!

https://youtu.be/ngERuezVd5o

J12MOC

802 posts

143 months

Saturday 23rd September 2017
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Pete is there any loss of performance y having the small silencers next to the cats?

Ian_UK1

1,514 posts

193 months

Saturday 23rd September 2017
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V8V Pete said:
Some really, really interesting stuff!
I also have a 2014 SP10 with BR's manifolds, cats and X-pipe. I've been in a similar quandary about the exhaust sound since the BR mods were done on my car. The car's exhaust sound in 'valves closed' mode is fine, but it's just a little too much in valves-open mode. It's not the quantity of sound particularly, it's the quality: towards the top of the rpm range it gets a little out-of-control, with a slightly unpleasant 'staccato' noise (I wish I could think of a better word to more-appropriately describe it).

There is a tendency for this to happen on many cars where 4 x 400/600-cell cats have been replaced with 2 x large-diameter 200-cell units. Most of the silencing afforded by the factory cats is lost and the standard exhaust is simply overwhelmed as it was never designed to damp-out the resultant decibels or harmonics.

Having discussed this with Mike at BR, he'd suggested exactly the mod he's done on your car. Unfortunately, I'd simply not had the time, over the last few months, to leave my car with BR to do the development work. So, I was absolutely delighted to read your post and to find the 'Confused Moggies' are now designed and a reality.

I'll definitely be contacting Mike on Monday to book my car in for the same modification. The only thing I'm not sure about is whether I'll keep the X-pipe or not. I personally like the 'flat-plane crank' sound it produces. Very 1st-world problem though - do I want my car to sound full-NASCAR or Euro-Supercar? Nice problem to have!

PS - I noticed the catalysers Mike's used in the Confused Moggies are slightly smaller diameter than the standard BR 200-cells you pictured next to them. Have you noticed any differences in performance from the slightly different setup?


Ian_UK1

1,514 posts

193 months

Saturday 23rd September 2017
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OMG - Only just read the second half of your post re the engine/tappets.

Same car, same year and BR had to replace all the exhaust-side tappet buckets (on both banks) in my engine earlier this year to cure the exact, same symptoms. WTF Aston....?!!

V8V Pete

Original Poster:

2,496 posts

125 months

Sunday 24th September 2017
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J12MOC said:
Pete is there any loss of performance y having the small silencers next to the cats?
Not that I can notice Martyn. My understanding is that the internal diameter of the pipe is the same but just with a perforated layer into the silencer. So would presumably reduce the laminar nature of the flow but (again presumably) much less than the cat itself does. As we all know the real performance gains are in having decent manifolds and a single high flow cat compared to two standard ones.

V8V Pete

Original Poster:

2,496 posts

125 months

Sunday 24th September 2017
quotequote all
Ian_UK1 said:
I also have a 2014 SP10 with BR's manifolds, cats and X-pipe. I've been in a similar quandary about the exhaust sound since the BR mods were done on my car. The car's exhaust sound in 'valves closed' mode is fine, but it's just a little too much in valves-open mode. It's not the quantity of sound particularly, it's the quality: towards the top of the rpm range it gets a little out-of-control, with a slightly unpleasant 'staccato' noise (I wish I could think of a better word to more-appropriately describe it).

There is a tendency for this to happen on many cars where 4 x 400/600-cell cats have been replaced with 2 x large-diameter 200-cell units. Most of the silencing afforded by the factory cats is lost and the standard exhaust is simply overwhelmed as it was never designed to damp-out the resultant decibels or harmonics.

Having discussed this with Mike at BR, he'd suggested exactly the mod he's done on your car. Unfortunately, I'd simply not had the time, over the last few months, to leave my car with BR to do the development work. So, I was absolutely delighted to read your post and to find the 'Confused Moggies' are now designed and a reality.

I'll definitely be contacting Mike on Monday to book my car in for the same modification. The only thing I'm not sure about is whether I'll keep the X-pipe or not. I personally like the 'flat-plane crank' sound it produces. Very 1st-world problem though - do I want my car to sound full-NASCAR or Euro-Supercar? Nice problem to have!

PS - I noticed the catalysers Mike's used in the Confused Moggies are slightly smaller diameter than the standard BR 200-cells you pictured next to them. Have you noticed any differences in performance from the slightly different setup?
Hi Ian. Happy to have been the test bed for this development! Regarding X-pipe, if you prefer the "Euro-supercar" sound then I suppose the logical thing to do is to keep it for now as it is easy to remove it later if preferred. Very happy to meet somewhere in the Peak District so you can hear mine in the flesh if that will help you make the decision.

As I said above I have not noticed any loss of performance with the change but it has not been on a dyno at any stage. I think the smaller diameter cats are the ones they use on some V12s so they can clearly cope with the flow.

Regarding the tappet bucket shims, personally I think there must have been a bad batch out there but I'm not an engineer so what do I know but it just seems like the logical explanation. Anyway, it is sorted totally to my satisfaction and I know where my car will be going for any work it needs from now on.

V8V Pete

Original Poster:

2,496 posts

125 months

Tuesday 26th September 2017
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V8V Pete said:
J12MOC said:
Pete is there any loss of performance y having the small silencers next to the cats?
Not that I can notice Martyn. My understanding is that the internal diameter of the pipe is the same but just with a perforated layer into the silencer. So would presumably reduce the laminar nature of the flow but (again presumably) much less than the cat itself does. As we all know the real performance gains are in having decent manifolds and a single high flow cat compared to two standard ones.
I have checked with Mike at BR and the silencers have a larger internal diameter than the intermediate pipes and gas flow is unaltered.

Ken Figenus

5,678 posts

116 months

Wednesday 27th September 2017
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That is a quality sound - it has the burble, the bass AND the top end squeal too. And you can close the flaps if needed. Great job & great write up.

Horrendous thought that some later engines have peanut butter shims? Hope this was just a couple of isolated cases.