?s about wastegates and BOVs?

[sonicsaleen]

Im trying to learn as much as possible about turbos due to the recently purcahsing of a TT cobra. So let me get this right The wastegates and BOV have springs in them to adjust the pressure. Im getting rid of the two bovs and getting one to mount on the cold side. So what spring do I need to get in it. Does it need to be the same as the wastegate springs. IM running somewhere between 15-17lbs of boost I cant remember. Someone give me the knowledge I need.

 

[tboothe]

Depends on what BOV you are getting.

 

[sonicsaleen]

Tial 50mm

 

[tboothe]

Im going twin tial 50 mm's on my set up. Bought them with heavy springs, but we are going to cut them a bit.

 

[sonicsaleen]

Nobody knows whats going on or what?

 

[sonicsaleen]

Can I use two tial 50 mm on my twin 57 set up only running 17lbs of boost. What springs would I use.

 

[04SilverSerpent]

All the springs do is set the minimum amount of boost your going to see essentially without a boost controller.

 

[sonicsaleen]

So if Im currently running 17lbs of boost and have two tial 50mm BOVs do the springs both need to be rated at 17lbs or one at 8.5 and the other at 8.5. I dont even think they make springs rated for 8.5lbs of boost

 

[TRBO VNM]

the wastegates are what actually control the amount of boost. if you are using a controller, then the setting on the controller might change based on the wastegates to maintain the same boost level. if your current wastegates have a spring and shims to maintain the 17# and you aren't using a controller, then you will need to shim the new wastegates accordingly to get the same boost level.

my turbonetics gate has a 9# spring. I can shim it to get about 14#, then I need a controller to obtain more boost. that is what comes with it as a standard. I might be able to buy a higher rate spring or something.

 

[smashedheadcat]

It shouldn't matter what springs are in the blow off valve. You don't want them very stiff. The spring should hold them closed and with a little effort, you can push them open. You have a vaccum/boost line that will run to the top of that piston. Vaccum in the manifold will open it and hold it open. In a zero vaccum/boost enviroment, the spring in the BOV will be biased towards closed. When boost pressure is present, the piston in the BOV will see equal pressure from the vaccum line (top of piston) and the charge tubing (bottom of piston). Since pressure will be equal on the top and bottom of the piston in the BOV under boost, it can be easily manipulated via a somewhat weak spring. If you run your BOV without a boost reference, spring rates inside the BOV become important.

 

[sonicsaleen]

So when they open prematurely it just mean that they need to be adjusted. Whether it be the screw type or add washers like my old ones. Im looking toward getting two tial 50mm BOVS. Im not sure if they are the screw type or not havent bought them yet. Do you think that they are two big.. The probem Im having is that one of the bov is staying stuck open or not closing all the way. Plus when Im driving in 4th or 5th gear while in vacuum they start going off one after another continously. I have 5 washers in each one and still not functioning right.

 

[tboothe]

Nobody knows whats going on or what?

I knew exactly what was going on and responded to exactly what you had asked BEFORE you edited the thread lol

 

[sonicsaleen]

Well I like the Tial brand and seen that you were thinking about getting two and I would love to keep two up in the grill so I too was also wondering.

 

[smashedheadcat]

Blow off valves are supposed to be open when in vaccum. That's the only time they should open actually. If they are opening and closing erratically, check the vaccum line that goes to the top port. Blow off valves are pretty simple devices and don't just "shit" themselves usually.

 

[sonicsaleen]

Thanks. I will check that.

 

[Juiced46]

You only need one Tial 50mm BOV for your setup. They are pretty large as well, you may not even be able to fit 2 on top of your IC. Just get 1 its all you need