Backbox Mod - 35is - Valved side only?

[Seb]

I have now had the 35is the best part of a month and absolutely love the thing . Looking on realOEM with the separated backboxes has got me wondering...

A couple of years back i owned a e92 335i and had a MPE 'mod' done to it. Effectively the perforated pipes within the backboxes were wrapped with a thin piece of metal so the perforated pipes were covered and the pipes were effectively straight through. Downside to this was that the mod rendered the exhaust vacuum flap essentially useless.

As far as I'm aware, the 35is has two backboxes, one of which sits behind a valved flap which is opened during throttle when you're giving it some beans.

My question is: Has anyone heard of modding only the valved side with an 'MPE' style mod? More noise when the flap is open (when you want the car to be loud) and more or less standard sound levels when the valve is closed?

Any inside pictures of the 35is backboxes would be great too, I can't seem to find much online.

 

[mcbutler]

You could mod the flap to permanently open for starters see if you like the sound, makes a nice difference.

Crawl under the car, pull the vaccum pipe off the valve actuator, get a suitable stick to open the valve with then place a rubber cap on the actuator so it stays open. You can buy caps for pennies from pipe/hose manufacturers
Then put another cap on the end of the vaccum pipe the other end of the little 'S' shaped hose was fitted to.

 

[clarker63]

makes a nice difference.

It does, but I've put mine back to stock. it just annoys the neighbours when I start it, and I dont really like the "wide boy" label I appear to be getting in my 50's!

 

[Seb]

Exactly the same as clarker63. I have installed a remote to control the vacuum flap, closed for the neighbours, then open when out on the country roads. I would just like to add some more volume to it without having to fork out for a valved system!

 

[Scoobycue]

Seb have you any details on how you did this please?