Active Exhaust / Bypass Valve
Discussion
Afternoon.
I am considering the possibility of fitting a switchable exhaust to my Griff and I was wondering if anyone else has looked into this?
My Griff currently has ACT MS03 S/S OEM replica manifolds (less precats), Clive F Y de-cat section and the ACT Cherry Bomb back box. In my personal opinion this setup is the best overall compromise giving a good roar when you are out on a blast yet not being too loud when cruising along the motorway.
The problem with this for me is that it is a compromise, there are times when I would like the system to be much quieter, for example those 5am early morning starts that make you want go to great lengths to avoid your neighbours for a few days, the same goes with getting home late..... wakey wakey neighbours!! Also on the motorway it would be nice to also turn down the noise a bit. There are also times that I would like the exhaust to be louder, for example runs out, tunnel runs etc.
After seeing a number of VXR8s with the switchable exhausts I have done some research the system and it works using an electronic cutout valve situated before the exhaust silencer. The cut outs on the VXR8s are provided by a company called DMH Performance although there are many other companies that make a similar product. The electronic cutout is controlled via a switch in the cabin.
http://www.youtube.com/watch?v=_ECVMuS37RM&fea...
This has got me thinking.....would it be possible to fit the same system to the Griff? My initial thoughts were to leave the system as it si (no cats and no precats) but to replace the cherry bombs with a very effective silencer so that it would be neighbour and motorway friendly (could also do trackdays). The cut out valves would need to be located before the silencers.
I am thinking that the cutout valves would give a hugely loud car when you wanted it but a nice and quiet when it needed to be.
I am considering the possibility of fitting a switchable exhaust to my Griff and I was wondering if anyone else has looked into this?
My Griff currently has ACT MS03 S/S OEM replica manifolds (less precats), Clive F Y de-cat section and the ACT Cherry Bomb back box. In my personal opinion this setup is the best overall compromise giving a good roar when you are out on a blast yet not being too loud when cruising along the motorway.
The problem with this for me is that it is a compromise, there are times when I would like the system to be much quieter, for example those 5am early morning starts that make you want go to great lengths to avoid your neighbours for a few days, the same goes with getting home late..... wakey wakey neighbours!! Also on the motorway it would be nice to also turn down the noise a bit. There are also times that I would like the exhaust to be louder, for example runs out, tunnel runs etc.
After seeing a number of VXR8s with the switchable exhausts I have done some research the system and it works using an electronic cutout valve situated before the exhaust silencer. The cut outs on the VXR8s are provided by a company called DMH Performance although there are many other companies that make a similar product. The electronic cutout is controlled via a switch in the cabin.
http://www.youtube.com/watch?v=_ECVMuS37RM&fea...
This has got me thinking.....would it be possible to fit the same system to the Griff? My initial thoughts were to leave the system as it si (no cats and no precats) but to replace the cherry bombs with a very effective silencer so that it would be neighbour and motorway friendly (could also do trackdays). The cut out valves would need to be located before the silencers.
I am thinking that the cutout valves would give a hugely loud car when you wanted it but a nice and quiet when it needed to be.
MPoxon said:
What is the rest of your system derek and where abouts where you looking at locating the valve?
Mines fully decatted so should be fun.
I will also be adding a side exit pipe to fit at the dragstrip. It will be below the height of the chassis rail and exit just behind the front o/s wheel. Better to spit flames at the Marshals than under the car!
clive f said:
moosehunter did this a few years ago, he fitted the valve into the pipework just alongside the sump.........deafeningly sodding loud!
Thanks Clive, I have sent Andy an email.dbv8 said:
There is enough room to 'slot' it in at the bottom of the Y-piece just ahead of the sump.
Mines fully decatted so should be fun.
I will also be adding a side exit pipe to fit at the dragstrip. It will be below the height of the chassis rail and exit just behind the front o/s wheel. Better to spit flames at the Marshals than under the car!
I will be very intersted to see how you get on with yours Derek, one of my concerns was about flames and fumes under the car. Where the silencers are located in the middle of our cars there is not much choice as to where to locate the valve. Fabricating a pipe sounds like a good plan.Mines fully decatted so should be fun.
I will also be adding a side exit pipe to fit at the dragstrip. It will be below the height of the chassis rail and exit just behind the front o/s wheel. Better to spit flames at the Marshals than under the car!
At one stage I was wondering if it was possible to install 2 valves before the silencer and but were the pips split into 2 and then linking this up with a quad exit exhaust or rejoining the main exhaust after the silencer. It seems like a lot of work and it might not even be possible.
The good thing about the valves is that you can vary the noise by having the valve only partially open or closed.
GasDoc said:
What about track day silencers. Not sure how much this cuts the dB by. Could these be put on before you start up, and then taken off once out of earshot of the neighbours? Seem to remember a post from an owner who did this. Anyone know if this works?
This thread is for making the cars much louder at the flick of a switch.Who said anything about being quiet or not upsetting the neighbours?
gizzer said:
Mines @ a flick of a switch 128DB , NO NEIGHBOURS THOUGH ,,, MAY BE AN ASBO
ON THE WAY!!!!!
I have heard yours gizzer and it is very very very loud! You haven't got a bypass for yours though have you?.... I thought it was permanently loud? What back box have you got on yours?ON THE WAY!!!!!
MPoxon said:
I have heard yours gizzer and it is very very very loud! You haven't got a bypass for yours though have you?.... I thought it was permanently loud? What back box have you got on yours?
Griffs have no back box, i remade the whole system in A2 s/steel, removed the l/rover centre box, and fitted 2 moto gp sleaves [bike type} to stop the tractor affecthttp://www.youtube.com/watch?v=H6EJI0oJuxU
gizzer said:
Griffs have no back box, i remade the whole system in A2 s/steel, removed the l/rover centre box, and fitted 2 moto gp sleaves [bike type} to stop the tractor affect
I did wonder what you setup you had on yours. Do you remember the make and model of the bike silencers you fitted to yours.I was thinking I could possibly combine this with Derek's idea of the side pipe but perhaps squeeze in a sleeve like you have.
Edited by MPoxon on Friday 11th November 14:44
I have looked into this before on my Wedge and the heat/potential and possible fluid getting onto the tyres put me off - I just removed most of the box (122 db) which I know isn't your goal but was also a fractin of the cost.
On my Griff however, the ECU has different settings at the flick of a switch so can go from quiet to 'pops and bangs' mode although as it is just changing the fuel mixture/set up it is not massively louder....
On my Griff however, the ECU has different settings at the flick of a switch so can go from quiet to 'pops and bangs' mode although as it is just changing the fuel mixture/set up it is not massively louder....
pjac67 said:
I have looked into this before on my Wedge and the heat/potential and possible fluid getting onto the tyres put me off - I just removed most of the box (122 db) which I know isn't your goal but was also a fractin of the cost.
On my Griff however, the ECU has different settings at the flick of a switch so can go from quiet to 'pops and bangs' mode although as it is just changing the fuel mixture/set up it is not massively louder....
I agree the heat, fumes, fluid and flames underneath the car are a concern which is why I am looking at either Derek's idea of the side exit pipe or possibly some way of getting an additional pipe to routed towards the rear of the car.On my Griff however, the ECU has different settings at the flick of a switch so can go from quiet to 'pops and bangs' mode although as it is just changing the fuel mixture/set up it is not massively louder....
Are you achieving the pops and bangs using an aftermarket ECU (Omex???) or are you still using 14CUX. I know you can provoke pops and bangs by adjusting the amount of fuel that is injected on the over run or if you have mapped spark then retarding the ignition on overrun = fireworks
May I ask how you have yours setup.Gassing Station | Griffith | Top of Page | What's New | My Stuff