Which exhaust a standard or cherry bomb?

[ChimpOnGas]

450Nick said:

I've still yet to hear anything even even half as good as my setup (I'm biased I know) - I have the ACT sports manifolds (decat) with the full stainless cherrybomb rear system. It is loud, but it sounds amazing - confirmed by the number of thumbs up and happy faces seen from just about all bystanders - definitely not annoying

If I'm right the ACT decat sports manifolds you speak of use four long separate header tubes on each manifold converging at the Y piece, IE like this....



My friend 'Frenchie TVR' has the very first set of the above design that were made many years ago by Peninsular TVR, according to Tim at ACT these manifolds became the template for the ACT decat sports manifolds, Tim even supported 'Frenchie TVR' in refacing and tidying up these Peninsular manifolds after Frenchie snagged them for a great price on eBay. On his 1996 5.0 litre Chimaera this system is very loud especially in urban areas, before he fitted these manifolds & Y piece set Frenchie's car always sounded like the original owner had ticked the sports silencer box on the TVR order form from new so perhaps that's why for me the end result while sounding amazing is 'a little too much'.

I've concluded it doesn't matter what you do with the rest of the system it's those long header tubes that make the biggest difference, not to the volume as such but they definitely enhance the quality of the sound, these type of long tube headers are in fact much more like what was fitted to the precat Griffs which probably goes a long way to giving precat Griffs their wonderful tone, I also bet TVR made them that way for good reason....



The very special precat Griffith sound has always been my holy grail target, I've got 95% there by decatting my cat manifolds and fitting an ACT Y piece but I think the only way to get that elusive last 5% will be to eliminate the nasty big voids where my pre-cats once lived. This manifold design change was clearly forced on TVR by the requirement to add precats, before this they chose the long tube headers so even decatted cat manifolds like mine should be viewed as a compromised design because you're always going to be left with short header tubes even if you fit reverse cones in those undesirable voids.



As such it seems the only way to get 100% of that glorious precat Griff sound is to fit long tube headers, which I guess means buying a set of these....



At which point I'd be tempted to go the full hog and follow Mathew Poxton's lead and fit a set of these...



Which would help deliver the only sound that truly beats the precat Griff, which is this....

https://www.youtube.com/watch?v=Hdp1fZsH9ck

Now that's what a Rover V8 should sound like

Whatever the changes the one thing I'll never be tempted to do is mess with my original silencer box, sleeveing is the easy option which is why so many people do it, but personally I feel quality of sound is more important than just a volume increase, it seems clear to me if you're to achieve a more tuneful result you're way better off leaving the silencer alone and focusing your attention on the Y piece and manifolds.

If you like, its the difference between a fog horn and a well tuned instrument

[swisstoni]

Wedges always sound great to me. I have no idea how their exhaust system differed from the later Griff and Chim but that was the sound I would be happiest with. Lovely burble.

[SILICONEKID 345HP 12.03]

Any decent fabricator can copy the ACT sports exhaust , mine cost me 150 quid .

Once you have converted or purchased the ACT sports exhaust what ever you do dont buy a decat Y piece its just to loud.

Keep away from the cut and shut sleeved conversion its a bodge and sounds like a tractor .

Dont use these


This was my conversion , very raspy .



This is the ACT SPORTS

[450Nick]

The concept of the long headers was originally derived from the RV8 Tuscan challenge engines; they ran bigger bore, longer primaries to gain more torque and higher gas flow. That's where Peninsula will have got the idea from and as you say, it determines most of the change in sound - the back part of the exhaust doesn't really change the character very much, but the cherry bombs do add a nice additional bass-y quality.

I think Clive's 8-4-2-1 manifold does look cool and was a nice idea for him to show off his fabrication skills, but I think it's a bit over the top for minimal additional gain!

[Matthew Poxon]

As with most modifications it is all down to personal preference. I think the best advice I can give is blag as many passenger per rides as you can before making your decision. Also think long and hard about what would be acceptable for what you use the car for. I actually quite like the sleeved silencer sound but it is a bit too much for everyday and I know I would quickly become tired of it.

A good post from Chimpongas as per usual and spot on with regards to the headers and Y piece, this is where you need to invest the money. The standard back box sounds great once you change the manifolds.

Like 450Nick I run cherry bombs on mine, the reason being Nick very kindly took me out for a spin in his car many moons ago when I was deciding what do with mine. One of the only times I got out of a 450 Chim that made made my Griff500 feel like a Ford Focus in terms of performance!

As per CoG's post I now run the Clive equal length system but I used to run ACT headers, Clive F Y piece and ACT cherry bombs, very nice setup and sounds like this:
https://youtu.be/tBQTZsk-6CM

450Nick said:

I think Clive's 8-4-2-1 manifold does look cool and was a nice idea for him to show off his fabrication skills, but I think it's a bit over the top for minimal additional gain!

Agreed in terms of performance, probably only worth 20ft/lb torque and a few BHPs so probably one of the least cost effective mods pound for pound BUT you need to hear it!!!! Sounds like a cross between a Cerebra and a GT40. Well worth the money for the aural experience. Hope you are well sir and I look forward to catching up about your GEMS install at some point soon.

[carsy]

Matthew that sounds awesome.

Can we have some more footage please.


Lets just put this here again.
https://www.youtube.com/watch?v=Hdp1fZsH9ck

Edited by carsy on Friday 26th May 19:20

[450Nick]

Matthew Poxon said:

Agreed in terms of performance, probably only worth 20ft/lb torque and a few BHPs so probably one of the least cost effective mods pound for pound BUT you need to hear it!!!! Sounds like a cross between a Cerebra and a GT40. Well worth the money for the aural experience. Hope you are well sir and I look forward to catching up about your GEMS install at some point soon.

I'd love to hear it to be proven wrong! Sadly I don't think it would fit around mine due to the supercharger stuff - I had to have a custom manifold made up already based around the ACT one to fit mine originally! Maybe Clive could do a special one day haha..

Defo up for a meet up to show you the GEMS - it just keeps getting better and better, it's by far the smoothest and best refined the car has ever driven and it's not even finished learning yet...

[SILICONEKID 345HP 12.03]

https://youtu.be/inEGGozMiXs