Disable exhaust valve to be always in quiet mode

[AC]

Hi all,

With the noise restrictions getting stricter I'm facing issues with my gt430 on most eu tracks. Has anyone run the exhaust, or engine protection valve as lotus calls it, it always closed mode? It would be simple to do but not sure if the backpressure would cause damage to the exhaust, cats or engine at high rpm track use. I have the ti exhaust fitted. 

Appreciate your experience or thoughts.  

 

[2011 Chrome Orange]

For what its worth... from the earlier Evora Service Manual:

The exhausts primary flow path is through a multi chamber silencing system designed to reduce noise emissions from the exhaust gas. This silencing system generates excessive back pressure at higher engine rpm (and power) which could damage the engine. Therefore, Lotus has engineered a second flow path (by-pass system)
that is controlled by a valve.

When this valve is open the exhaust gas passes through only a small part of the silencing system before exiting the tailpipes and with the reduced back pressure this offers, allows the engine to safely generate full power.
This valve is known as the Engine Protection Valve (EP Valve).

[Bravo73]

For regular (quieter) track use, you will probably have to change the back-box/silencer. 

[EGTE]

Out of interest, which tracks have caused you problems so far?

[TdM]

On 08/03/2024 at 21:49, 2011 Chrome Orange said:

For what its worth... from the earlier Evora Service Manual:

The exhausts primary flow path is through a multi chamber silencing system designed to reduce noise emissions from the exhaust gas. This silencing system generates excessive back pressure at higher engine rpm (and power) which could damage the engine. Therefore, Lotus has engineered a second flow path (by-pass system)
that is controlled by a valve.

When this valve is open the exhaust gas passes through only a small part of the silencing system before exiting the tailpipes and with the reduced back pressure this offers, allows the engine to safely generate full power.
This valve is known as the Engine Protection Valve (EP Valve).

I think this translates to:

'We wanted to make it louder but that's illegal so we worked around the rules and called it protection'