Cytrax

Today I went to my nearest Scooby garage and when he took a look inside my engine he saw my bleed valve in there., he kinda made a funny noise like Uh Oh!!! I was like "whats the problem??" He then told me that running a bleed valve is going to probably cause me some engine problems and reduce the life if not kill the engine. So there I went advice in hand and came home and took it off, now I notice a major performance loss, Turbo is not boosting nearly as much as when it was in :S, Should I stick it back in???

Also once its in do I run the air mixture rich or lean ??? Is it right in saying the less air the quicker the car will go

Please correct me if I am wrong

Ste

jb2000

what year of car please

Cytrax

I decided to post a picture of the beed valve that I am using, would someone let me know if its best to have less air being released or more being released?

RICH WILD

A bleed valve is a crude way of raising boost pressure on a turbo car. If used correctly, they aren't inherently dangerous but they aren't the best way of controlling boost and can be inconsistent in the boost pressure they produce.

The danger comes when too much boost pressure is run without the other necessary modifications to fuelling and cooling.

Running more boost is putting more air into the engine, so the more boost you run, the more the car has a tendency to run lean and also the more danger there is that you will start to get detonation which will eventually wreck your engine.

A bleed valve on it's own is ok if set to a sensible boost pressure and providing you can monitor for knock (you need a knocklink really) and you should really have an in car boost gauge to monitor the pressure you are running. I would also get the fuellling checked to make sure the car is not leaning out, especially at high rpm. A permanent AFR gauge is the best option so you know for yourself how the car is fuelling at all times.

Rich

Cytrax

After reading arround scoobynet I have picked up some great tips and info, Number one is dont use a bleed valve unless your motor has some uprated aftermarket parts to cope with the extra strain induced on the engine,

The Scooby stock Boost is 0.5 so I am told, and safe Boost with a bleedvalve and without a knocklink is 0.7 now getting my bleedvale set to that 0.7 mark was not happening and I was going well over into the 1.5 mark, When I told the mechanic this the first thing he said was "CHECK FOR A SUPERCHIP" I did as he said and to my surprise sitting next to the ECU was an external little box with JAP writing on it, I told the mechanic about it and he was surprised that it was a JAP one and not some crud U.K one and that would explain the nice boost levels,

I sat here scrathing my head not liking the fact that the lowest I could set the car to boost with full open on 4th with the bleedvalve on was 1.2bars and that aint good so I took off the bleedvalve and made myself something that was not going to let too much air in but still give me a little more boost seen as there is a chip in the ECU,.

where the origional bleed valve was I took that out and replaced it with a BIRO pen, you know the plastic ones with a tiny hole in it? now that sits in the gap where my monster of a bleed valve was, now to my supprise and glee my motor boosts all the time @ .07 .08 bars and no more and seems to have no exessive pressure release on the dump valve.