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Old 05-10-2013, 04:13 AM   #21
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Something is fucked up. Its not keeping closed at lower rpm but its not opening enough at high rpm.

Are you using ecu controlled wastegate or is it the standard internal wastegate?
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Old 05-10-2013, 08:10 AM   #22
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Internal wastegate. I'm going to lengthen the arm today and try again.
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Old 05-10-2013, 08:25 AM   #23
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Why are you messing with the boost control in megasquirt then?
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Old 05-10-2013, 09:11 AM   #24
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Quote:
Originally Posted by triple88a View Post
Why are you messing with the boost control in megasquirt then?
Yeah, now I know. I have been extremely confused as to why people keep telling me to tune the boost control even after I mention I do not have EBC. But several high ranking members over the last year kept insisting that is what I needed to do. I'm still learning.... obviously.

And about the chart I made. I don't think you can really draw a lot from them. They were in different conditions, different roads, and possibly different gears and maybe not all at WOT. Maybe if I put all of my long pulls together I could determine more from them.
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Old 05-10-2013, 09:25 AM   #25
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You should set the wastegate this way and dont **** with it.

I'm very much against using the adjustment arm to increase or lower boost. Its not made for that. Its strictly made for preload and preload only. To increase or lower the boost you'll need another wastegate for the boost you want. In your case you should check the line going from the intercooler to the wastegate, It either has a hole in it or the wastegate it self is fucked.

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Old 05-10-2013, 02:58 PM   #26
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Thanks for the video. I do have a question though about adjusting the arm. The actuator is advertised as being adjustable from 7 - 11 PSI. Assuming everything was working as expected, isn't that how I would adjust when wastegate starts to open. I'm just asking because I am not 100% sure.
Thanks!
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Old 05-10-2013, 03:27 PM   #27
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You see they can advertise them as much as they want.. Theoretically you can adjust it from 0ish psi to all of it. Here is the problem with that theory. There is a set psi spring in the wastegate. Its suppose to open when it reaches the configured psi.

So to make this easier, let me give you an example. Say the wastegate is set for 10psi. Theres 3 scenarios.

Scenario 1. The preload is set correctly, the wastegate opens at 10psi and stays open to keep the turbo at 10psi and everything is correct. 10psi all across the rpm range.

Scenario 2. You want to run less pressure (say 8psi) so you adjust the wastegate looser to lose pressure. In this case the wastegate will actually be halfway open because its too loose. Theres no preload to keep it shut therefore you will lose a lot of middle rpm boost since the flapper is open. So in this case you get low pressure in the middle rpm that slowly increases to 8psi by redline.

Scenario 3. You want to run more pressure (say 12psi) so you adjust the wastegate tighter. Now theres too much preload so spool up is normal however when it reaches 10psi, the wastegate starts opening and as the exhaust flow increases the smaller tighter opening limits the maximum flow so you get up to 12psi. In this case you get 10psi in the middle rpms and then slowly increase to 12psi from there.

Last edited by triple88a; 05-10-2013 at 03:39 PM.
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Old 05-10-2013, 03:34 PM   #28
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triple88a,
That makes sense. I will check the signal line.
The wastegate does open and close. I could move it freely with the actuator arm disconnected or connected.

I can try and move the signal line back to the original location on the throttle just to compare.
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Old 05-10-2013, 03:51 PM   #29
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Take off the line and check it. Bend it in all directions inch by inch to ensure its not cracked.
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Old 05-10-2013, 03:58 PM   #30
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Quote:
Originally Posted by travisb View Post
I can try and move the signal line back to the original location on the throttle just to compare.
That won't make any difference.

You could try a test with the signal line connected to the compressor outlet nipple. What you are looking for is the disappearance of the spike. If it doesn't disappear, then the can is bad (not reacting fast enough/leaks). If it does disappear, then the signal line has a problem (clogged or has a leak).

Note that the disadvantage of connecting to the compressor outlet nipple full time is boost sag at high RPM (not compensating for IC pressure loss). But that won't make any difference for this particular test.
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Old 05-10-2013, 05:10 PM   #31
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Ok. So I did a test before I read the latest replies from triple88a and hornetball.

First, I adjusted the arm as shown in the video above. I shortened it 3 full turns from where it just fits easily.

Then I moved the line back to the throttle. I did a 4th gear pull and a 1-4 pull. I maxed at 161 kpa.

Then I moved it back to the IC pipe. I did a 1-4 pull, 4th gear pull, and another 1-4 and 4th. I maxed at 157 kpa and the MAP graph looks ok (to me ).

The logs are attached below.

So, what was the cause? The signal line was tight on the IC pipe connection. The actuator arm did not change until I started playing with it yesterday. Currently it is a couple rotations tighter than it used to be.

So I'm not sure what the issue really was. Do you think the issue is resolved? It seems ok to me now.

Thanks everyone for your help!
Attached Files
File Type: msl on_throttle_intake_2013-05-10_14.48.38.msl (159.1 KB, 42 views)
File Type: msl on_IC_pipe_2013-05-10_14.58.26.msl (360.0 KB, 81 views)
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Old 05-10-2013, 06:23 PM   #32
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My guess is that your wastegate actuator is sticking when fully relaxed. By adding the preload, you moved its resting position to an area that's free.

Guess, mind you. I've never heard of this happening before, but I can't explain it any other way. So, you're looking good. Keep an eye on it.
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Old 05-10-2013, 08:07 PM   #33
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Thank you. So in continuing my education, I have another question.
Is it possible to increase boost beyond my current level without installing an MBC or EBC? I'm guessing the answer is no. And I have the EBC from the previous owner that I could install ( EBC Electronic Boost Control Solenoid Kit DIYAutoTune.com ). However, it looks like I need this boost control mod kit too: PCBv3 and v2.2 -- Boost Control Mod-Kit DIYAutoTune.com
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Old 05-10-2013, 08:22 PM   #34
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Ways to increase boost:

1. Tighten the actuator arm . . . add preload. Will only go so far and subject to the issues mentioned by Atanas in Post 27.

2. Add external helper spring (search -- several examples on the site).

3. Change wastegate actuator to a unit with a stiffer spring (will be rated for a higher PSI).

4. Add MBC.

5. Add EBC. The solenoid you have is all that you need. The MSPNP already has the EBC circuitry inside of it. Reference the MSPNP documentation here: MegaSquirtPNP by DIYAutoTune.com.
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Old 05-10-2013, 10:15 PM   #35
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Add a MBC from ebay and move on.
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Old 05-17-2013, 05:26 PM   #36
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I was looking forward to start installing the EBC today, but on the way home from work I had a problem. While accelerating I hit over boost at around 12 PSI. It happened one more time after that when I was just checking to see if it would happen again.

The actuator is still set like last week. It is tightened 3 full turns from fitting comfortably on the wastegate arm.

I can pull the actuator arm and move the wastegate. I disconnected the actuator and moved the wastegate around. It does hang a little bit when it is completely open.

I have four pictures below.
1 and 2 are how the actuator is currently connected to the wastegate.
3 is the wastegate hanging closed
4 is the wastegate stuck open as wide as possible

The wastegate moves smoothly up and down except for when it reaches full open. It is not difficult to close though. If the actuator pushed it that far, and I am not sure it even can, then it should easily close it too.
Attached Thumbnails
new boost spike-20130517_154655.jpg   new boost spike-20130517_154805.jpg   new boost spike-20130517_154338.jpg   new boost spike-20130517_154349.jpg  
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Old 05-17-2013, 05:53 PM   #37
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Picture 1... why is it crooked? Is the rod all crooked going in the wastegate too?
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Old 05-17-2013, 06:08 PM   #38
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Quote:
Originally Posted by triple88a View Post
Picture 1... why is it crooked? Is the rod all crooked going in the wastegate too?
Are you referring to the area highlighted in the attached image? If so, I don't know why it sits like that. Maybe I can turn it...
Or the actuator arm itself?
This is the actuator I have: 7 psi Turbo Actuator, 48009-9 BEGi
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new boost spike-20130517_154655-copy.jpg  
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Old 05-17-2013, 06:20 PM   #39
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Yes take a pic of the arm entering the wastegate too pls. Look at begis image, even though the arm is crooked the part of the rod entering the wastegate is straight. Thats what you want. If the arm entering the wastegate is on a large angle it will not function properly.
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Old 05-17-2013, 06:29 PM   #40
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Here are some more pictures.
Attached Thumbnails
new boost spike-20130517_171402.jpg   new boost spike-20130517_171417.jpg   new boost spike-20130517_171503.jpg   new boost spike-20130517_171617.jpg   new boost spike-20130517_171631.jpg  

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