Author Topic: Waiste gated (Read 5422 times)

Darkness_is_spreading · « **Reply #15 on:** July 24, 2008, 11:20:53 am »

I am considering the options of adding a BOV based on the issues of compressor surge because I have a Hybird turbo that I have built and am worried about surging the compressor vanes.....

I have been doing some reading and yes gas turbo cars need BOV because of throttle plate ( or massive loss in airflow).... Air has no were to go and needs to be vented, isn't this the same case if your running up the gears and hit 22 PSI and then say you need to let off or need to engine break ( were does the excess boost go)......

I am setting my wastegate to open around 22-25 psi, but I am worried that if the exhast impellar is unloaded(wastegate open) and the compressor still having the left over boost is still loaded may surge.

So if I tap into the wastegate line which senses compressor pressure and run a line to the wastgate, they should open simultaneously, allowing the turbo to have a balanced amount of pressure between the compressor and impellar.....

gigaz2 · « **Reply #16 on:** July 24, 2008, 01:01:19 pm »

but... thats how wastegated turbos regulate pressure already...

they surge because of the inertia of the spinning parts, ant the time it takes the wastegate to actually move and let the exhaust gasses out.

they only surge for that brief period of time, but bad things happen quickly

OM617 · « **Reply #17 on:** July 24, 2008, 02:51:41 pm »

Quote from: "Darkness_is_spreading"

if your running up the gears and hit 22 PSI and then say you need to let off or need to engine break ( were does the excess boost go)......

Through the engine, there is no throttle to block airflow.

jtanguay · « **Reply #18 on:** July 24, 2008, 03:05:09 pm »

i would imagine that boost would also leak past the compressor wheel as it spools down... a BOV couldn't hurt anything though... except your wallet :lol:

dillenger1 · « **Reply #19 on:** July 25, 2008, 04:05:10 pm »

I have a k26 from i believe an audi 5000 .it doesnt have a wastegate.At least on the exhaust housing.Would there be problems with running a bov in replace of a waistgate to regulate boost?

OM617 · « **Reply #20 on:** July 27, 2008, 06:22:34 pm »

Quote from: "dillenger1"

Would there be problems with running a bov in replace of a waistgate to regulate boost?

Yes, the compressor wheel would explode when it overspeeds.

dillenger1 · « **Reply #21 on:** July 28, 2008, 06:18:16 am »

Not to thread jack,but does anyone know why these(k26)didnt have a waistegate?Could it have been on the manifold some how.I dont see a pressure line anywhere on the compressor?

MJF · « **Reply #22 on:** July 28, 2008, 06:55:40 am »

5cyl gasser Audis have external wastegate.

Smokey Eddy · « **Reply #23 on:** August 02, 2008, 04:09:54 am »

Well....

i plugged mine with a cork and she FLIES now. especially with more fuel and massive downpipe and no cat or muffler just 3 inch pipe. watch that egt though

foxracer1 · « **Reply #24 on:** August 02, 2008, 09:18:06 am »

It seems the factory setup would sacrafice the turbo to save the engine. ie. headgasket, maybe rods. In the event of a wastgate failure.

OM617 · « **Reply #25 on:** August 02, 2008, 01:40:11 pm »

It looks that way.

Author Topic: Waiste gated (Read 5422 times)

OM617

OM617

OM617