View Full Version : airbox flap
Hi all.My 5s running the standard airbox and cold air feed but has no thermostat or hot air feed from the turbo. Does this meen the flap in the top of the air box is restricting the cold air flow.thanks
Didn't you ask Wizard this?
Yeah but he mentioned the intercooler,not airbox
you might have to re-read his answer.... i think he's changed it in light of him misreading your question?
you might have to re-read his answer.... i think he's changed it in light of him misreading your question?
Thanks:agree:Probably my fault for not explaining it right.
Flight666
13-10-2012, 07:08
I have often wondered how this system worked.Can anyone explain how it exactly works? It looks to me like the flap opens whilst on throttle due to the air pressure pulling it open and sucking through the hot air feed on idle due to the flap being closed,but why would it be pulling the hot air in? Sorry for my crappy explanation just curious as to how the set up worked..I`m sure I remember the the flap being called a "thermostatic flap" when I had a previous 5 many many moons ago.
I thought it worked off somekind of thermostat in the top of the air box.?
I thought it worked off somekind of thermostat in the top of the air box.?
I think your correct mate:agree:
Jimmy_GTT
13-10-2012, 13:16
There is a bi-metal at the bottom and it controlls tha flap.
When air is warm it opens only the cold air intake but when it is cold it opens the intake from the turbo.
I was out in the 5 yesterday having a nice drive when a Guy in a Porsche boxter decided it was ok to drive on my rear bumper so I gave it some beans in 3rd and not only shocked him but shocked myself as well,the car felt a touch quicker than normal,I then noticed my afrs were low 13s so I backed off(normally high 11s)for some reason the spring had come off the airbox flap,put it back on and afrs were back to normal? :confused:
Could be due to the fact its colder outside now and the spring falling off the airbox flap let more air enter the engine than normal causing the afrs to lean off a bit.
Best off glueing the flap or fitting a zip tie if running more power than standard matey.
Best off glueing the flap or fitting a zip tie if running more power than standard matey.
Thanks.I thought the flap worked on vacum pressure?after yesterday I may be wrong or mine wasn't opening properly?zip tie it is,then turn boost down.
Remove all the thermostat gubbins and route an extra cold air feed to what was the hot side.
Thanks for the replies everyone,for now I have blocked the warm air feed,tied the flap up and turned the boost right down,fingers crossed:( no damage was done.
I doubt a quick blast will have hurt it. Just rejet the carb to suit?
With the flap in place it was jetted for 16psi and was plenty quick enough for me,the increased air flow took me by surprise a bit,as well as the boxter dr:burnrubber:iver.lol
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