Hey guys ive been doing a ton of research and havent come up with a solid answer. i Have a couple questions.
Running a S475 Turbo at 8 PSI. I have a Tial BV 50 Blowoff (one top port) and Turbosmart wastegate with two ports.
I have XFI FAST system controlling the boost with a Fast Boost Controller.
Question One. What should be my spring pressure for the blowoff? Whatever spring keeps closed at idle?
Question Two. What should be the wiring/tubing for the blowoff.
Question Three. What is the spring pressure for the Wastegate? I was told two times the boost. (1.5x-2.5x)
Question Four. What is the wiring tubing for the waste gate?
Question Five. I am getting confused on what valve is getting controlled by the boost solenoid. Are both controlled with the same controller. Does the wastegate just rely on spring pressure?

Please ANYONE. Im am in dire help. Trying to do a TPS vs BOOST

Any help would be grateful. Ive searched the internet but have not found a conclusive answer to the Wastegate.

Video of the corvette i am working. Please Check Out!! Thanks guys!

[video=youtube;6T6-Bt4K_90][/video]
--------------------------> http://tinyurl.com/hxph53k <----------------------- PART 2

 

1) Yes, just ensure it's closed at idle. It will open up while driving when you chop the throttle and engine vacuum is highest.

2) Blow off valve needs a vacuum/boost reference line, meaning it needs to come from the intake manifold (after the throttle body).

3) The wastegate directly controls the MINIMUM boost pressure. Since you have an external controller, you can get a spring that opens at 4-5psi, then use the controller to increase that amount. The controller will never be able to make the gate crack open UNDER the rated spring pressure.

4) Your boost controller manual should show you a diagram for the hose routing. I'm not sure whether your solenoid is 3 port or 4 port so I wont discuss an answer until that is established.

5) The boost solenoid only controls the wastegate. The blow off valve is plumbed independently from the gate/control system and literally only needs the one hose from the manifold.

 

I think you have a few things confused between bov and wastegate. Also looks like you have the bov at the angle you would a wastegate not a big deal but bit overkill. Never seen it done quite that way. Normally it just installs at a T perpendicular to the charge piping and optimally pre intercooler/closer to the turbo outlet since the purpose to prevent air from surging back through the turbo. Although they still work where you have it.

1) For bov it needs a vac/boost source ie off the manifold and spring pressure should be about half of your warm idle vacuum. so if you have -20 vac 10lb spring. I prefer to set it up so the bov is just barely closed at warm idle. There is no harm in going a tad lighter on the spring if you have to but avoid being too stiff as it will be slower to open or not fully open if the spring is too stiff for your engines vacuum.

2)Bov just needs a hose plumbed to a vac/boost source like mentioned.

3)Wastegate spring pressure basicly determines your min boost and the controller can let you run more boost than spring pressure roughly double depending on port connection method at the wastegate. Most common is a single side port method. So from the boost controller solenoid you go to the side port on the gate and leave the top port open. This allows the solenoid to cycle and bleed off pressure to the side port allowing you to run more boost than spring pressure would open at. If you want more than double spring pressure or a wide range of boost ie 5-40psi etc. You can use a 2 port method where the second line form the solenoid doesn't vent to atmosphere but instead goes to the top port on the wastgate. The top port receiving pressure keeps the gate closed. This would allow you to get 20psi for example on a 6psi spring. But back to single side port which is most often used. So say you had a 10lb spring in the wastegate, you will make no less than 10psi. Often a little more not using the controller or having it off, duty cycle to zero due to setup and flow/back pressure etc. The controller will allow to run about double that so 20psi by adjusting duty cycle of the solenoid which bleeds pressure reference away from the gat and keeps it closed longer. So spring pressure should be selecting based on desired min boost and range usually. For example. The min boost I run is 12psi and max is 20psi. So I have an 11lb spring in the gate.

4)Wastgate can get plumbed many ways, since your using a controller. Your controller maker will have schematics on how to plumb it. For good generic ones you can check out turbosmarts website. I used a single side port method with my boost controller. The solenoid wires go to the boost controller which allows it cycle the valve in the solenoid to achieve desired boost set by the controller.

5)The bov is solely mechanical and runs off plumbing to its single port from a boost/vac source. It purpose to relive pressure in the charge piping when coming off throttle to prevent compressor surge. The wastgate is what controls boost. It can be run purely mechanicly off spring pressure or a manual controller. Or electronically via a solenoid and an electronic boost controller.

Never messed with a tps based boost controller. I use my controller with preset setting based on max boost I want to run at the time. Hope this helps.

 

Treed

 

Indeed lol

 

It's a 3 port boost controller. Thank you all for your help. I'll be asking more questions when I get back to the car this weekend. Thank you so much!!!

 

for a 3 port solenoid, use this diagram.

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You sir are hero and a gentleman. Thank you

 

FYI that is not the only way to setup with a 3 port, that's just one of many options depending on boost goal. That's off turbosmart website btw like mentioned which has greater detail on which method works best for what. I use the single side port method with my 3 port solenoid.

Here is the diagram for 3 port solenoid with single side port on the gate. This is the simplest way that works great with less hoses and connections. Every dual port method I have done on a car sees a rise in min boost.

http://forums.pelicanparts.com/uploads24/11453033771.jpg


This method would be good for roughly 8-20psi tops if you have a 8lb spring. If you want more boost than double spring pressure go for a dual port method. You may see a rise in min boost though over spring pressure so keep that in mind.

 

I found that my FAST Sportsman does not control the boost. I will have to use a standalone system. In the meantime can i hook up my wastegate like this? I do not understand how this would increase my boost pressure. When this attached to the lower port, it would only decrease the boost . Any explanation would be great. My wastegate is like below, 2 port.
I have a 5 psi spring and trying to achieve ~10psi.
Correct if I'm wrong. Please.

I tried to message 5.0thunder but its tripping.





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A wastegate works by using boost pressure from the turbo to lift the wastegate diaphragm (and valve consequently). This bleeds pressure from the hot side of the turbo system and disables additional pressure creation by keeping the turbine from continually increasing speed. That's why we introduce boost at the lower port (under the diaphragm) FYI, so that it lifts the valve. The spring will be able to resist a certain amount of boost until it is forced open. This is the "rated spring pressure" we've been talking about. When you installed your spring in your gate, it was pre-loaded to where the diaphragm needs to see roughly 5psi before the gate cracks open.

This boost controller effectively restricts the boost signal going to the gate, so it has less lifting power on the diaphragm. This means you need more boost before the controller (at the compressor) in order to make the gate valve lift. This is why you get an increase in boost pressure when you install this controller. The more you "turn the knob" the more it restricts the signal, meaning higher boost in the cold side.

Hope this helps

 

Okay, 5.0 I tried messaging you again but you don't exist. I understood everything. I see some people are using this setup.
This looks like the controller I have, I also noticed that some people do a bleed method. Where they have it on a Tee and use the controller to bleed off. So there's a bleed method and a block method from what i understand..

What would be the best for my setup? The turbosmart single port above? This dual port method below?

Sorry for the stupid questions, I did some searching. It appears there's more than one way to fry an egg.

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For YOUR setup going from a 5psi gate spring to 10psi boost pressure, the method in your post #10 is easiest. The other "teed" method can achieve the same thing but in that case, you're giving full pressure to the bottom of the diaphragm so it always has full lifting power but you're also allowing pressure to the top of the diaphragm that acts against your lifting power, which is how it increases boost pressure. Both work, they just differ in what happens if they fail or clog.

If the controller gets clogged in the first "straight" method, you'll skyrocket your boost until the gate cracks open from exhaust pressure alone, which can cause super high boost pressures (blown motor if not fixed immediately).

If the controller gets clogged in the 2nd "teed" method, the car simply runs on wastegate pressure, which is safe.

If the controller somehow fails fully open in either case, the opposite effect occurs. both can hurt you depending on the failure.

Another difference is that the Teed method I believe has the ability to achieve higher max boost pressure if desired (you don't desire this currently). I want to say this is due to the pressure placed on top of the diaphragm. It's harder to move the diaphragm against that pressure from above, even when there is the same amount of pressure below the diaphragm.

 

@TTF/Ken private messaging not working?

 

Thanks alot.

To me your profile does not exist, therefore I cannot message you.

 

I figured I would add to this post,

So the problem im having is that the S475 is not making any boost. We have a White spring -9.0 psi in my BOV that appears to be closed or nearly closed at idle and does open up if I chop the throttle. I measured my vacuum and found it to be around -17. Now for the wastegate, i have a 5psi spring installed with the configuration shown in post #10. The problem is we are not achieving any boost, on the gauge, and on my computer(MAP). EVEN though i hear the blow off clearly cycling, like a normal boosted application. WHAT IS WRONG!!!

s475 Not making boost, I plugged the line going to the BOV to force it closed, and it still didn't make boost. So I think it has to do with the wastegate? Maybe the s475 takes awhile to spool and my quick burnouts are not making boost??

Even if I go down the street and lay into for a 1/4 mile it's not breaking 100KPA on my MAP which i'm told is more or less atmospheric, or 0psi (>100)
Someone please tell me where i went wrong.

 

Fist thing that comes to mind is a coldside boost leak. Are you hearing the turbo spool? What trans? What type of intercooler? How is pressure routed to the wastegate?

 

What wastegate?
There are some that require a fire ring be installed between the v band flanges. No fire ring and there is a 1/4" gap around the wastegate valve.