Bora w/R32 exhaust - flapper mod?

**Dyldo** · 17-10-2010, 10:28 PM

I've read all through the Vortex and google searches of the flapper mod, and most relate to the stock exhaust for a R32 that will have the famous blue/grey wire they all talk of.

My goal when I get my R32 exhaust fitted to my Bora (this week hopefully) is to have the flapper open. Now, my question (seeing as how this is an exhaust taken from a R32 and fitted to a non-R32) is that if i pull the vac line off the vac actuator nipple and cap it with a screw and/or silicone to seal the line and also cap the actuator nipple, then will this mean the exhaust is in the "open" position?

**type 17** · 18-10-2010, 01:02 AM

Does the standard bora exhaust have a butterfly valve? i.e, do you even have a vacuum line to block? as far as i can tell, if you have a vacuum line for your exhaust that would normally plug into the valve then yes, you only need to jam a screw in it and the flap will stay constantly open.

PS, just started fishing through your emails today mate, looking interesting, sorry ive been a bit flakey but ive been dealing with some issues recently, havent had much time to think bout cars..

**Dyldo** · 18-10-2010, 12:38 PM

nope, the Bora's don't have a flapper or butterfly, so no ECU leads or vacuum lines leading back to the engine bay.

Is there a way the butterfly valve can be actuated from either in the cabin with the exhaust this way? As in because its in a Bora now the flapper (I presume) needs to be either locked open or closed. I am still getting used to the flapper idea tbh, and its not fitted yet.

Or am I missing the way it operates? I am presuming it is like the butterfly on the Varex adjustable muffler?

**Manaz** · 18-10-2010, 02:37 PM

My understanding is that vacuum forces the flapper to close - so if you block the line off (or remove it and plug it up), the flapper stays in the open position.

Just make sure there's a bung in the attachment point - that way you'll keep dirt out of it if you should ever want to use it later (there are kits to enable it with a switch - pretty sure ECSTuning sell something along those lines...).

**type 17** · 18-10-2010, 10:05 PM

yeah if there is no vacuum line at all the flapper should be jammed open all the time, just check and if its not get a clamp on the little lever so it is open... but yeah without the correct vacuum line with computer programming you will not be able to achieve the stock open-close flap arrangement of the .:R32

**Dyldo** · 18-10-2010, 10:18 PM

thats fine man, i'd rather have it as manual. as in, forced closed if the missus/boss/fun police wants to have a whinge, and left open 95% of the rest of the time

actually bugger that, i want that puppy open all the time.

how would i get the exhaust to give me a burble as well as some crackling, popping and farting on over-run?

**type 17** · 18-10-2010, 10:23 PM

well, the r32 makes bubble, popping and fizzing noises from standard if the flap is open, i did the grey/blue wire mod and have the switch sitting in the cabin for easy adjustment, that said i usually drive with it on standard mode, unless i wanna freak someone out, or piss my parents off when i go to visit them...

**Dyldo** · 18-10-2010, 10:26 PM

nice - i'll leave it then. sure the engine pumping gases through the system is a slightly different (smaller) engine in the Bora than the R32, but surely the result will be the same?

and you say keep the centre res in?

**graeme86** · 18-10-2010, 11:14 PM

Actually...it would not be too difficult to get the flapper to work on a Bora with a manual switch.

You would need the vacuum tank and solenoid from R32 (or a vacuum tank and a solenoid - just one of those generic VW green vacuum tanks on some VWs and the solenoid is the same as the variable inlet solenoid on the Bora).

Then you would need a vacuum line from the manifold - the R32 connects at the back where the three pipes are on the manifold.

Then you just wire a fused positive to the solenoid from the 87F terminal on the relay plate to the solenoid. (same as R32...or just use 75X which is ign)

The negative from the solenoid just goes through and on/off switch to earth.

Thats how it operates on the R32 - the earth for the solenoid is actually controlled internally by the ECU, so when it earths the signal, the flap is closed.

Porsche also have a separate plug-in relay (not the ECU) to control their flappers on 996 etc Tequipment package Sports exhaust. but it also connects to GALA speed signal so that it only opertes similar to R32 system - only at "out of town " speeds