JDL turbo kit owners thread

[Amputechture]

Originally Posted by djwishbone

Is the top position the best spot to mount the turbo? It seems popular but others have placed it in different areas. I can see how they all have their benefits and detriments, but I'm curious why you guys chose that area?

9 out of 10 turbo kits for this platform place the snail there for a reason...quicker transient response. If you compare JDL's charge piping to let's say, PTuning or AVO...there is much less real estate that the compressed air has to travel across and not as much drop in pressure. Some may argue that the difference is negligible but I disagree...I was worried that running a journal bearing would ruin that quick snappy feeling you get when you engine brake and that I would experience rev hang/hesitation all over but that is not the case.

[Jonathanlim]

I'm having some over boosting issues. Just wondering if anyone knows. I hit 22pi on a data log, and my tune was set for 7. I found a 25psi spring installed in the wastegate and had to install a 7psi spring. For some reason I'm still overboosting. Not sure if I routed the vaccum line right or the wastegate is defective.

[Amputechture]

Originally Posted by Jonathanlim

I'm having some over boosting issues. Just wondering if anyone knows. I hit 22pi on a data log, and my tune was set for 7. I found a 25psi spring installed in the wastegate and had to install a 7psi spring. For some reason I'm still overboosting. Not sure if I routed the vaccum line right or the wastegate is defective.

What is your setup, wastegate pressure only? Can you share a picture of how you have your vac lines routed?

[Jonathanlim]

I used the yellow spring which is 7psi. I have a automatic and Not sure if it matters or not. I read something about a brake booster, and a check valve. The pic circled red is my line directly to my BOV. I have a ecbs and I routed mine like this.

[Amputechture]

Sent you a run-down text Jonathan. The only thing that should tap into the brake booster line is BOV if you opt to use that for your vacuum source. Question about your red circled port for BOV vac source....if you are looking at your intake manifold standing in front of your car w/ the hood popped are you using the port that is on the left (PCV Valve to intake manifold connection in OEM form) or right side port?

[djwishbone]

If you pipe the turbo only to the wastegate you shouldn't make any more than spring pressure. Would be a way to test the wastegate. I'd say it's your ebcs if I were to guess. Who tuned your ebcs?

[Amputechture]

Originally Posted by djwishbone

If you pipe the turbo only to the wastegate you shouldn't make any more than spring pressure. Would be a way to test the wastegate. I'd say it's your ebcs if I were to guess. Who tuned your ebcs?

I'm confused as to how he overboosted with the way his wastegate was routed. Both vac hoses are being sent to the top air ports which would allow him to make boost until he hits the spring pressure of 7 and it should shut at that point. I know this because my dumbass set it up this way at first.

[Jonathanlim]

Maybe my wategate is Defective

[Lee@JDLAutoDesign]

Originally Posted by Jonathanlim

If this is how you currently have the wastegate hooked up, assuming you don't have any additional lines that aren't visible in the picture, then the wastegate is working more or less exactly like it should be.

Pressure applied to the bottom ports on the wastegate (beneath the diaphragm) OPENs the wastegate, resulting in less boost.

Pressure applied to the top ports on the wastegate (above the diaphragm) CLOSES the wastegate, resulting in more boost.

As a rough rule of thumb, derived with a few assumptions:

- If you run with pressure applied to the bottom port and you leave the top ports open to ambient, you will make ~1x spring pressure. This is more or less the standard configuration without a boost controller.

- If you run with no connections to the wastegate (which is the same as running equal pressure on the top and bottom ports), you will make ~2x spring pressure.

- If you run with pressure applied to the top port and you leave the bottom ports open to ambient, you will make ~3x spring pressure. Based on the picture above, I believe this is more or less what you are doing.

If you would like me to elaborate on how/why this happens, just let me know...

My suggestion to you and anyone else is to get the car up and running with a boost signal straight to the bottom port on the wastegate, leave the top port open to ambient and verify everything makes ~spring pressure or close to it before adding the boost controller in.

Good luck!

[Amputechture]

- If you run with pressure applied to the top port and you leave the bottom ports open to ambient, you will make ~3x spring pressure. Based on the picture above, I believe this is more or less what you are doing.


Unless he has an air port without a fitting threaded in that is not pictured in the photo, he is basically running with turbo source going to both top air ports and all lower air ports are blocked off. Meaning that it would allow the WG to open up and allow flow to the turbo until he reaches the 7 PSI target...and then it shuts completely. I am asking because this is what happened to me, my BOV would vent and it felt like someone jabbed at the brakes. I am trying to understand if what I just described was actually happening and it caused the car to go into vacuum suddenly, or if I was actually making that much boost and boost cut kicked in.

[Lee@JDLAutoDesign]

Originally Posted by Amputechture

Unless he has an air port without a fitting threaded in that is not pictured in the photo, he is basically running with turbo source going to both top air ports and all lower air ports are blocked off. Meaning that it would allow the WG to open up and allow flow to the turbo until he reaches the 7 PSI target...and then it shuts completely. .

*** This is just generic advice that has worked for me in the past. You should consult with your EBC vendor for specific advice. ***

I think you are misunderstanding the purpose of the top port vs. the bottom port on the wastegate. Applying pressure to the top port pushes down on the wastegate, which closes the valve and increases boost. You will NEVER make target spring pressure when you are sending ANY pressure to the top port on the wastegate. Even some EBC instruction manuals will make mention that once you install a solenoid and start feeding the top port on the wastegate you should expect some increase in your minimum boost level beyond spring pressure, even when the EBC "gain" is set to zero.

The rated spring pressure will ONLY be reached when you run a direct boost source to the bottom port on the wastegate and leave the top ports open to atmospheric pressure.

Turbosmart has a pretty good manual showing several different ways of setting up an EBC and external wastegate with 3 and 4 port solenoids.

http://www.turbosmartusa.com/wp-cont...19-MAY-121.pdf

Look at pages 8 and on. You'll see that there are three basic concepts. First concept is regulate/restrict the air going in to the bottom port and leave the top port open to atmosphere (pages 8 and 9). By reducing the pressure reaching the bottom port you delay the opening of the valve and make more boost. The second concept is to send full pressure to the bottom port and regulate the pressure send to the top port (pages 10 and 11). By applying some pressure (beyond ambient) to the top of the valve, you push down on the valve and hold it closed longer. The third is to regulate pressure to both the upper and lower port (pages 11 and on). This allows you to control pressure on both sides of the valve and gives you the ability to make the maximum amount of boost. There are pros and cons to each method, but you'll notice that all methods require air going to the bottom port and the top port is only used when the user wants to make more than spring pressure.

I don't recall all of the details of your recent issues, but to me it sounds like the BOV venting is a symptom of your issue, not a cause. My first impression/guess was that you were hitting a boost cut, which caused the car to cut out, which pulls a vacuum and opens the BOV.

Hope this helps!
Lee

[Spartarus]

Originally Posted by Jonathanlim

Maybe my wategate is Defective

You're using the wrong ports on the wastegate.

You've hooked up both lines to the 2 top ports.

I'll send you a diagram and edit your pics to illustrate when i get off of work.

Originally Posted by Amputechture

I'm confused as to how he overboosted with the way his wastegate was routed. Both vac hoses are being sent to the top air ports which would allow him to make boost until he hits the spring pressure of 7 and it should shut at that point. I know this because my dumbass set it up this way at first.

Think of it according to this simplistic explanation.

The wastegate stays closed until you reach (close to) target boost.

With manifold pressure applied to the top port, the wategate is forced shut by the combined spring pressure and boost pressure. No exhaust bypasses the turbine (which is the purpose of the wastegate), it all goes through the turbine. It would be like running with no wastegate at all. Boost climbs with RPM. (until you had enough exhaust energy/pressure to force it open, but that's a discussion about intake and exhaust pressure ratio for another time)

Opening the wastegate allows you to control how much air is bypassed, and limit the amount of energy you use to spin the turbine.

You always need one line on the bottom (opening) port.

Controlling pressure sent to the top port with a solenoid allows you to force the gate closed so that you can raise boost above spring pressure.

[Jonathanlim]

Thanks everyone my problem is fixed. I had to remove the fitting to the bottom where it says air.

[Jonathanlim]

Originally Posted by BRZ68

Can you show me which specific fitting on the bottom port you took out? Im having boost creep as well.

By how much? I was over boosting to 25psi, I'm suppose to be at 8psi. Wategate routing was incorrectly done.