Turbo lag

beermonster said:
a vent to asmosphre dump valve is basically for show, usually the air has been measured by the MAF and the ecu injects the corrosponding amount of fuel to air, but this air is vented to atmos so the rich mixture also causes flaming/popping etc, the best way is to have a recirc dumpvalve
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What?

It completely depends on the car, the way the ECU takes its air flow readings, and the scenario in which its used. :/

A recirc diverter valve is needed on a 1.8T BECAUSE of the MAF, that isn't to say that for other cars, the "best" way is a recirc, because it isn't always the case.
 
I didn't think they did. You can hear the diverter valves "whoosh" if you listen carefully.

You certainly can on mine anyway.
 
Aye, mine does that, but its nowhere near as pronounced as a vent to atmosphere valve.

You hear a whooshing of air when the throttle is released, but its enclosed.
 
[TW]Fox;11926173 said:
The Golf GTI I drove had a very, very quiet dump valve, presumably as standard.
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I am pretty sure on mine there's a "diverter valve" (same sort of function as a dump valve I presume?) which is standard. They must have done the same sort of thing for the mk5s?
 
Begbie said:
I thought dump valves can't be put on diesels anyway?
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You can buy kits to fit a dump valve to your TDi if you are considerably lacking in mental capacity. For the truly retarded you can even buy a box and horn speaker that plays a digitized dump valve noise...
 
how do these dump valve kits work on diesels? I always thought they don't have a throttle. However I was stood next to the 320d when the MOT tester did the smoke test and it deffo made a quite loud dumping noise when he lifted off from max rpm.
 
Right, from this point onwards, a turbo may not be referred to as a mechanical system.

Instead, the turbo and all the little devices supporting it will now be known as witchcraft, this change will drastically improve the accuracy of turbo threads.
 
I was overtaken by a VX220 turbo yesterday (which I followed to a set of traffic lights gawping and dribbling). When he pulled away and changed to second then let off for the next set of lights, there was a distinct "Tsscchhh" which actually sounded cool. I would never consider sticking a sound box or kit on a car that didn't actually require it.
 
dump valves/blow-off valves/diverter valves are all different solutions to the same problem - preventing compressor surge by venting boost.

I like hearing the sound if it's subtle, but I hate cars with really loud blow-off valves fitted, sounds too fast and the furious.

Having a 1.8T, I've gone for the best option - a forge 007p diverter valve.

the 2.0T's, like the golfs, have the crappy plastic standard diverter valve like 1.8T's had, forge have recently made an upgraded one for them too but they are on back order. The standard ones are really quiet, the forge ones give you a slight increase in noise but not much. The best way to increase noise is to get a remap - more boost = more venting noise as there's more boost to vent.

As for the OP's question, if you are getting increasing lag stick it in the garage as somethings obviously wrong

or fit an anti lag system :D
 
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