I need something simple and cheap. I just want to be able to set a boost level, have the wastegate 100% closed until it reaches that level, and then have it flutter the wastegate open and closed (or whatever they do) to maintain that boost level. I don't need anything more than that (e.g. no warning lights, ricer scramble mode, etc).

If you have something used that would be great too, or if you know of one that is pretty cheap new.


Thanks!

 

I got this PM from a fellow board member and have not done this mod but I think its what you are looking for.

The setup I discussed completely blocks the signal from the wastegate until a set pressure. Once this pressure is obtained the wastegate opens. This is fastest spool you can get. Normally a wastegate begin to open long before the wastegate set point. So you get a progressive boost increase. Most commercial boost controllers bleed the boost signal to atmosphere which means you get a higher boost setting than stock but slower boost response.

The disadvantage of my setup is that if the relief valve fails shut you will get uncontrolled boost. This is really not a problem with a good working boost gauge.

The parts I used were the following from www.swagelok.com:

B-4CP2-1/3
Brass 1-Piece Check Valve, 1/4 in. Male NPT, 1/3 PSIG Spring $12.00 each - this is a fixed pressure check valve

B-4CPA2-3
Brass 1-Piece Adjustable Check Valve, 1/4 in. MNPT, 3-50 PSIG (this can be used a a relief vave) $17 each. this is adjustable with a allen wrench from 3-50 psig set point which can be adjusted with the use of a mighty vac

Then you need what ever fittings you want to hook it up to your car.

This setup was specifically designed for the single port internal wastegates but would work for a dual port actuator as well.

 

just a simple manual regulator you can put together for dollars works ALLLMOST as good as the highest dollar controllers.. I would just pick up one of those... however it will not hold the wg 100% closed until peak boost.. and honestly neither does my turbosmart.. it has an independent wastegate pressure setting that you dail in for optimum spool with minimum overshoot.

 

Those parts sound like exactly what I need! If I can do this mechanically I'd prefer, as I want the simplest solution possible. Maybe you guys can help me figure this out? I'm pretty new to check valves and such.

I connect my boost reference (vacuum line) to the valve (B-4CPA2-3), so no boost will go through until it reaches the set point. At that point the wastegate (which will be set well below the valve boost rate) will then open quickly, lowering the engines boost until
the check valve closes. The boost will build up again and the process will repeat, probably several times a second?

With this type of a setup, will the boost effectively regulate or will I see it continually bounce above and below the set amount?

Also I don't quite understand what I'd do with the valve (B-4CP2-1/3).

Thanks in advance!!!

 

It sounds like you are describing a PWM scheme for your boost control. I suppose such a control method is possible but, most wastegates are somewhat linear in nature. There is some spring, diaphram/piston assembly thingy in the wastegate that uses the intake boost pressure to control how much exhaust gets bypassed, no need to modulate. The electronic boost controller described above will convert the linear nature of the wastegate to a step function.

 

This is from my setup. It was designed for the Incon kit, which has only one actuation line instead of two. The actuation line pulls a vacuum and supplies boost to the actuator. The relief valve inlet (adjustable check valve) is placed toward the engine. The check valve outlet is placed toward the engine. When you have vacuum (no boost) the relief valve is closed and the check valve (.3 psi crack pressure) is open. You go boost, check valve shuts.

Ideally the relief valve cracking (opening) pressure will be about 3%-5% lower than the desired controlling. This type of relief valve does not crack open until the point you set it and the wastegate is completely shut. This relief valve is considered a pop-safety valve in that you get no leakage until the crack pressure. The crack pressure is setup by adjusting a set screw. You get boost control because the check valve valve opens with at .3 psi delta pressure and the fact that it has the same flow rate as the relief valve. This way maximum boost will be less than 1 psi from the set point but more likely within a .5 psi. I have never tried the is setup on a two line actuator but should work as both valve were placed on one of the lines. You could not just use the relief valve by itself since you would have huge pressure swings.

A manual regulator just slows the boost signal from getting to the actuator until the set point is reached. A lot the manual controllers use these. Its somewhere in between a bleeder setup and boost block for turbo spool. All of the electronic setups I have seen use a bleeder solenoid.

However, be careful with this setup it going to make low end traction even worse, say anthing less than the middle of 3rd gear . Anyway hope that helps. If anybody need more information let me know. I don't mind giving out this information. Gives me something fun to do instead of the usual aerospace part testing.

Gary

 

Hey Gary, I shot you an email for a little more help..

Thanks!
Terry

 

Gary, thanks for coming in. I dont give out member names without asking so Im glad you saw this. I smoked my rings before i could try this setup.

 

No email, just pm me. My email and webserver at work are pretty picky. I can't even get this webpage at work due to all the bad traffic from this site (port scanning etc). Anyway boost is probably jumping around a little. I have a digital boost gauge so its going to miss some of the quick spikes. Since the the two valves are matched boost spikes and repeated boost changes should not be to bad.

This setup is not adjustable from within the car, I would rather not do that. Although I have a design for a setup that could be adjusted in the car. It just replaces the adjustable check valve (set screw) with a **** adjustable back pressure regulator (relief valve) but I have not tried it. I have test the back pressure regulator by itself its very precise two rotations of the **** is 1 psi. I can provide the part number if someone wants it.

Gary