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Russ_C70_Cab
Tuesday 8th August 2006, 21:12
I was on the Kalmar Union volvo specialist website and saw this

"Bleed valve: Adjustable, in turned aluminium to control operation of turbo wastegate. Will give good horsepower/torque increase with carefull adjustment."

Is this a statement true or total bull?

Thanks Russ

Wobbly Dave
Wednesday 9th August 2006, 17:00
A bleed valve is a preset air leak. Essentially you are by-passing the ECU's ability to reign in the boost - by fooling it into thinking there is less boost so it holds the wastegate shut for longer. Very crude way of tuning. It doesnt takes into account intake temps and you are bypassing the safety feature of the ECU to not bend rods (too high boost at low rpm)

If you set the bleed to high you can damage your engine. Seriously would not buy one. If you must then fit an MBC (manual boost controller) (but even these are risky IMO). Cheap form of power but the temptation to increase may cost you more than you bargained for. Like the ad says you need careful adjustment.

Much better to save for a remap IMHO

volvotuning
Wednesday 9th August 2006, 17:08
And if your car is 1999 or later model, then don't bother fitting one at all. You will get an engine light very quickly.

Adam.

gtiteen
Wednesday 9th August 2006, 17:13
I had a bleed valve on my 854 T5 and ripped it off straight away, not matter what i did it would overboost. Dangerous game fitting them.
Dave

Russ_C70_Cab
Wednesday 9th August 2006, 18:36
Cheers Lads wont be getting one of those