Waste gate and blow off valve not working together

[Poweystroke96]

Hey guys, i am in need of some help, I am looking at buying a 2008 f350 that has had some work done. I took it for a ride today and from what I could tell the waste gate and blow off valve are not working right or in tune. if you are in between easy and full throttle you can hear one of the two letting off pressure but if your into it neither activates till letting off. If i get into it like half throttle it would buck like it would get into the power then dump so lose power right on a shift and you get the idea. But if i was easy on it or laid into it, the thing felt great through and through, power and shifting wise. So I am unsure of how to tackle this problem if I buy the truck. I figured the blow off valve was overkill so I would shut it down and try and tune the waste gate in and see how it does there. Any input or thoughts on this would be much appreciate.

List of mods include:
egr delete with wastegate setup and manual pressure regulator
bd turbo guard blow off valve on intake side of intercooler
arp's
spartan dashdaq running 310 tune i think it is
4in dp to 5 in exhaust
cfm elbow
cai

[jesilvas]

The WG should only work once a certain high level of boost is attained . . . correct?

[08stroker250]

If the wastegate is dumping to the exhaust, you shouldn't hear it. If the wastegate is tuned properly, it shouldn't open until a certain back pressure psi and it should dump all excessive back pressure off. The blow off valve is the only thing you'll hear. It should make a noise when you chop the throttle. It's blow off excessive compressor surge to keep your turbo's alive.

[Poweystroke96]

The wastegate is dumping to its own down pipe, i understand the basics of each device just that its hard to tell which is going off when, it sounds more like the blow off valve is set too low then as it activates at medium throttle but not all throttle. I am not even sure the waste gate was activating. Does this problem with the way its acting sound like a matter of tuning between the two?

[jesilvas]

The BOV sounds like it's wrong completely. It should only activate once you let off the throttle and you have excess boost not being used. Do you know which brand is on it?
You can only tell if the WG is working if you can see it. You say you don't know when it's working but then think it's not at all. You won't hear it.
How is the WG dumping into it's own DP? The truck has two?

[08stroker250]

Blow off valves are a waste in my opinion. I'm kinda confused on what you're talking about with the wastegate dumping into it's own downpipe....

[jesilvas]

This? If so, it's an aftermarket one right?
Cause I would think the OEM one is similar to this

[Poweystroke96]

There is a pipe going off the wastegate that goes down the back side of the motor, its like a one inch piece of steel pipe.

Its hard to describe as I don't know which one is activating. The blow off valve seems overkill to me too unless your running 1000hp and really do need the extra release of boost from the system. its a tial blow off valve.

The waste gate is aftermarket, it appears that it is from one of those kits that people like EDE sell with their egr delete as many say that blocking the egr requires a wastegate to prevent too much backpressure(i believe, please correct me if im wrong)

[08stroker250]

Yes, it has an aftermarket external wastegate. Most wastegate kits will dump back into the downpipe somewhere. They don't typically dump to atmosphere. 6.4's don't have a wastegate setup from the factory. The EGR valve kinda acts like a wastegate on a stock truck.

You're having issues with the blow off valve it sounds like and I would eliminate it or set it differently so that it isn't as sensitive.

[Poweystroke96]

Originally Posted by 08stroker250

The EGR valve kinda acts like a wastegate on a stock truck.

This is what I was referring too, thats what I was thinking, either take it out completely or try shutting it off and testing the wastegate through and through to make that it is working properly, i was kinda surprised to see the wastegate have its own downpipe