Active Exhaust Cutout Valves - now with videos!

[Rusty]

Not sure on performance, it's so loud you don't have the capacity to notice a pony here or there

[re2500]

My idea for fitting is virtually identical to what you have had done, as I also have no centre silencer, and I wanted an invisible exit, so it's nice to know it all fits nice.

[Rusty]

I'll take you for a run sometime, it's proper silly on fully open.

[JP]

Be interesting to see how it lasts. I had an electronic one and it sheered the teeth inside the gearbox jamming it permanently open.

Putting that aside before it broke when the valves was open the car was gutless low down and lost its torque so it was only of use alleviating back pressure at the top end. So what I did I logged egt's with it open and with it closed and it showed no difference when measured pre turbo. (Valve located near back end of gearbox).

So then when the gearbox failed I decided to add an actuator to it that opened at 1bar. This was great gave me my low down torque and quiet cruising and then the racing rasp when open. This lasted about 2days before the tension on the butterfly from the actuator and the heat in the exhaust warped the butterfly causing a permanent farty exhaust blow. So now the whole lot is being ripped out for something else to be tried.

[re2500]

We'll catch up soon, the coupe is getting close, just need to source a decent oil cooler. I'll pop over and bring the grill

[Rusty]

Interesting read there JP, I was a little worried about that so have to see how it goes...

[JP]

I think you have 2 advantages one its further back so heat effects it less and secondly had it supplied and fitted by same company so if gearbox fails they need to sort it.

[Rusty]

What turbo was the low torque on? I can't say it's much different but then I've not really tested it and prefer the valve open only.a bit to give the best noise level.

[JP]

Gt3079r

[Rusty]

So a large turbine then! I'm sure it was all flowed too, so back pressure pre turbo would have been minimised!

[Mcstiff]

Looks/sounds cool; I think I'd go with a boost actuated valve like http://www.spracingonline.com/spblog/?p=131

[Rusty]

There must be some sort of controller for the electric ones too. What I would need is a boost switch and a subsequent timed pulse in one 'direction' before a slightly longer one in the other, hardly rocket science for a sparky engineer. This would open the valve an amount between a little and a lot and then ensure that it closed when the throttle was let off. All good fun.

I didn't buy this as a performance upgrade but more as something to just enjoy on the rare occasion where some extra character would be a really nice addition to the driving experience. I managed to give it WOT in 1st, 2nd and 3rd heading on to the motorway and it just sounded great and I also showed my displeasure at a caravan overtaking a truck on a 2 lane motorway The switch location is perfect for simple operation - I'm glad I put it there and not on the dash and can always fit a spare ciggy lighter if I get rid of it...

Just emailed them to see if they do a controller. QTP do one for their valves but I'm not sure what it uses as a trigger.

[Rusty]

@ JP, another thing with my exhaust is that it's still of the order of 2.5 metres long, so will offer both a bit of back pressure, although not much and the tuning frequency will be lower than for just a 1m DP.

Ideally, I'd have fitted the valve at the rear and bypassed the rear silencer to throw more of the noise out the back (it vibrates the whole car!) and make 100% open more usable but there's just no space with the big rear box I have, so it had to go in the cavern where the centre box used to sit.

[caterpillar]

i have in my pc a link to the ready to go ; backbox WITH the valve mounted.. think it was from austalia.... AND it wasnt very expensive too... will have a look again

[Rusty]

Is that an all-in-one solution? Like the BMWs have where one tail pipe is controlled by a valve?