PhilMorrison

Does anyone offer a solution to change exhaust valve control?
I've never been a fan of the cold start, and now I've installed a Kline Innovation exhaust, the car just sounds broken for the first 20 seconds to me.

To add to that: The closed pre 4k, open post 4k is perfect to my ears. But if it were possible to use the exhaust button to create a valves closed 100% of the time to pass low db trackdays that could be incredibly useful.

unotaz

You probably don't want to do that. Closing the valve at high rpm manually will build up too much back pressure and it will harm the engine over extended period (e.g. Track driving)

bronson7

Wow, you're probably the first that I've heard of that wants to tone the sound down. Everyone else wants to turn it up a notch or two.

CDinSing

I've been thinking about keeping mine open all the time but keeping the ability to close them for the wife. Fabspeed sells a set of control valves that replace the CPU controlled ones so the valves become completely manual. Not tried them but did the research. That said I agree I would not run with them closed at the track. That would generate more heat next to the heads. Not sure it would create a mechanical problem but the restriction would reduce power.

http://www.fabspeed.com/fabspeed-val...ontroller-kit/

Lukas_at

I can tell you from my experience since I had broken valves from the fabspeed side muffler bypass.

I am not sure I understand the problem from OP ... the valves are open when you start the car and slowly close in the first 2-3 seconds. If you dont like it quiet with the exhaust valve button they open. Without gas input they always open standing still. If you start accelerating they close and open again at about 3500 (with exhaust button pressed). So I think thats one of the cars which can control the loudness of start on stock and on default they close but if you press the exhaust button right after startup they stay open.

What I wanted to say with keep the valves always closed ... one of the valves was broken and did not open anymore if they got hot .. means they stuck in closed position and you get a **** load of vibration and rattle with this over 4k rpm .. frankly speaking I did not drive over 3-4k until this was fixed because it was horrible. However since that wasnt fun at all I unplugged the valves and so they stayed always open. Please keep in mind that was with side muffler bypass ...

Bartron

There was a great thread on here last year where someone rigged the valves to a GPS control unit for Laguna Seca. The valves would close when near the sound check booth.

This may be a potential option for you if it's specifically track related.

The thread is here.

TRAKCAR

Im having Fabspeed key fob override installed now.
I'll report in next week.

The exhaust button is completely useless in the RS

tonymission

Whoa, what's that?

Jamie@dundonmotorsports

The cold start is cam timing related. Need a tune to make it completely go away... The exhaust flap control is also possible with a tune...

TRAKCAR

Just leaves the flaps always open or always closed regardless of RPM.
You lose TQ down low with flaps open but it's a little louder.
You lose power at higher RPM but it stays a bit quieter.

I hate the auto open/close, it's useless.
The button in the car does nothing but make a bit more noise at idle ONLY.

Kobalt

We (Europe) have the opposite problem: The car sound so much in original that we need to add stuff like this:

(Nürburgring - Spa is not a problem but some tracks very tough sound restrictions.)

PhilMorrison

I guess it's just personal taste. To me the GT3 sounds like *** when it first starts with an aftermarket exhaust that retains valves. It's loud but not in a nice way. I'm not particularly sensitive. My LP640 is also very loud on startup, but doesn't sound like *** .
Reprogramming to reduce the coldstart row is common on E9X M3's in the UK, I figured it may be on GT3's too.

As I said in the first post: Once the car's warmed up a bit, the standard tunes valves closed pre 4k rpm and open post 4k rpm is perfect to my ears for the majority of use.

Regarding Track DB mode: I was sure that I'd read about Rennlisters mechanically tying the exhaust valves closed for entire track days with no ill effect. I would like the option on the exhaust button to do this if possible.

Nick Yoskin

Yes, possible that EGT will increase and in turn harm the exhaust valves.
I am not saying that it will or will not but back pressure does increase EGT.

SamG

Are these available to purchase or custom made?

John@Fabspeed

We do indeed sell this valve controller kit to have the option of opening or closing the valves at all times. However, please keep in mind that the valves will always be in the default open position until enough vacuum pressure builds in the system to close them. This is why it is always a loud cold start, and unfortunately there is nothing to resolve that particular couple second delay before you can close the valves.

I will also concur to not run the factory PSE system in constant valves closed position during higher RPM track abuse. There has been no R&D as far as we know on the long term reliability of the engine under that level of backpressure, but we always recommend to be safe rather than sorry

Sorry to hear you had a valve issue! i hope everything was handled in a timely and efficient manner for you. If not you can give me a call directly at my numbers below and i'd like to hear more about the situation.

This was a brilliant thread and to this day I shoot it over to various clients of mine. They have done the same for the 981 platform as well if i'm not mistaken.