How do I get unlimited boost?

MyEclipse5 · 07-21-2007, 12:28 AM

I can't boost over 5psi with my boost controller, and I've done many leak tests with no results. To check to see if its just me being stupid and not doing the test right, or my MBC/actuator/hardware failure I was wondering if there is a way to hook it up so that it SHOULD just boost unlimted.

I have an aftermarket boost controller, so as soon as it builds over 7psi I'll shut her down cause I enver get that high as it is.

Is there a way to do this?

dsmpokolm · 07-21-2007, 12:32 AM

Why the hell would you want unlimited boost. Good way to blow shit up. What turbo are you running? You probably just have the MBC hooked up wrong, When you turn up the boost on the MBC it doesnt do anything? Maybe your MBC is broken. What kind of MBC do you have? If you have a ball a spring get one, or electronic.

MyEclipse5 · 07-21-2007, 12:36 AM

Quote:

Originally Posted by dsmpokolm

Why the hell would you want unlimited boost. Good way to blow shit up. What turbo are you running? You probably just have the MBC hooked up wrong, When you turn up the boost on the MBC it doesnt do anything? Maybe your MBC is broken. What kind of MBC do you have? If you have a ball a spring get one, or electronic.

I don't want to RUN unlimted boost, I just want to see if itll go over 5psi. Maybe im wrong in assuming that a turbo spools, which means its not going ot hit 20psi in .02 seconds. It takes time, and as soon as I see it jump im going ot let off.

14B
I can turn the screw in all teh way and out all the way and it still boosts to around 5psi.

I'm T'd into the BOV, but I KNOW it wouldn't cause this much trouble. I know tis not "wise" but this is not a discussion on that, so don't even mention it, please.

And its the voodoo MBC.

I have hooked my boost controller up both ways, and when it was hooked up the other way it definitly ran like crap. I would go run outside and check to get you details, but its night time and I don't have a flashlight (just moved into a new place, long story).

Once again, its not like I'm going to floor it and just wait till shit blows up. I'd take it easy, but I wanna see if I can build ANYTHING over 7psi.

djmixerx · 07-21-2007, 02:57 AM

take off the vacuum line off the WG. plug up the vacuum line though

ilikespeeding · 07-21-2007, 03:23 AM

Your turbo might be oil caked. You can run atleast 12 psi all day long. Take off the inlet pipe and try to rotate the blades by hand. If it doesnt rotate pretty easily, then you're going to want to clean your turbo out. It's pretty easy.

calan · 07-21-2007, 04:31 AM

Run a line from the boost source directly to the wastegate. You won't get unlimited boost (which could be uncontrollable and hard to predict), but you should get 9-11 psi, or whatever the spring pressure is on your WG actuator.

This will take the MBC and everything out of the loop for troubleshooting, but still provide a measure of safety. If your boost jumps up to the 9-11psi, you know there is an issue in your MBC or related plumbing. If it stays at 5psi, there is most likely a turbo or WG actuator issue.

And you said not to mention it, but I will anyway

. If you know that tapping off the BOV is not the proper way to get a boost source and you are troubleshooting a boost issue... how about doing things the correct way first and then go from there

Just my .02 .... good luck!

Talesin · 07-21-2007, 05:44 AM

I do hope you have an aftermarket boost gauge, and aren't assuming 5 based on the in-dash unit... which is just the ECU guessing at what boost you're running.
I especially hope you didn't install a boost controller without an actual boost gauge first!

And yes, taking the vac line off the wastegate actuator will make it pretty much never open (aside from leaking) but is a great way to blow your engine to bits, potentially literally. A vac line directly from the compressor outlet elbow vacuum fitting to the wastegate actuator should get you a good, reliable ~10psi.

MyEclipse5 · 07-21-2007, 10:58 AM

(~UPDATE~ I just went to my MBC, unscrewed the thing all teh way, and all that was in there (that I could see) was a ball. Maybe the spring is be hind it? Couldn't take the ball out to test, but would a springless MBC cause these problems?)

Reliable is better than uncontrollable, just didn't know it was an issue.

Yes, I have aboost gauge, I've had 3 DSM's, this is just my first with bigger mods on it, and I'm not that dumb, lol.

Stock gauge reads over 14, so if I'm going by that im doing good, but my aftermarket reads about 5, so no good there.

I have a FMIC with bigger J-pipe and there is no nipple, I also just moved and don't have anything to tap into it with, so for now the BOV line is going to have to work. Can I eliminate the MBC and go straigt from the T in my BOV line?

Quote:

Originally Posted by ilikespeeding

Your turbo might be oil caked. You can run atleast 12 psi all day long. Take off the inlet pipe and try to rotate the blades by hand. If it doesnt rotate pretty easily, then you're going to want to clean your turbo out. It's pretty easy.

Spins freely btw.

MyEclipse5 · 07-21-2007, 11:14 AM

Another update:

Went from manifold and T's at BOV one end goes to BOV other went to wastegate, and no change. Still have a hard tiem hitting boost almost at all.

I'm thinking I have to have a MAJOR boost leak somewhere. I'll guess I'll wait till I can get my buddy to look at it, since I must be doing something wrong when I test it.

turbosax2 · 07-21-2007, 11:45 AM

Quote:

Originally Posted by MyEclipse5

I'm thinking I have to have a MAJOR boost leak somewhere. I'll guess I'll wait till I can get my buddy to look at it, since I must be doing something wrong when I test it.

Describe for us how you do a boost leak test.

MyEclipse5 · 07-21-2007, 11:56 AM

Quote:

Originally Posted by turbosax2

Describe for us how you do a boost leak test.

well see the problem is that I have a tank I fill with air, and not a compressor.

I put my boost leak testor on the turbo, hook up the tank, and I hear the air but it never pressurizes the system. which is why I think im doing it wrong, or my boost leak testor is crappy.

turbosax2 · 07-21-2007, 12:00 PM

Quote:

Originally Posted by MyEclipse5

well see the problem is that I have a tank I fill with air, and not a compressor.

I put my boost leak testor on the turbo, hook up the tank, and I hear the air but it never pressurizes the system. which is why I think im doing it wrong, or my boost leak testor is crappy.

How did you make your boost leak tester? Can you feel air escaping between it and the turbo? It sounds like you have a major boost leak probably near one of the couplers for your ic. If you have a leak you should be able to feel and hear the air coming out. For smaller leaks, spray soapy water everywhere air can escape and if air is escaping bubbles will form.

1stGenRocks · 07-21-2007, 12:01 PM

i think you have a massive boost leak and i think you need to try getting rid of the mbc tapped into the bov since we know that will leak. straight wastegate boost is more then 5 psi. just cap the t in your bov line and drive it around the block with no boost controller hooked up.

MyEclipse5 · 07-21-2007, 12:01 PM

Quote:

Originally Posted by turbosax2

How did you make your boost leak tester? Can you feel air escaping between it and the turbo? It sounds like you have a major boost leak probably near one of the couplers for your ic. If you have a leak you should be able to feel and hear the air coming out. For smaller leaks, spray soapy water everywhere air can escape and if air is escaping bubbles will form.

I'm by myself and I have to hold the tanks line on the boost leak tester so I can't go around feeling for leaks.

I know i know get another person to help, but I work A TON and on my days off most of my friends work.

turbosax2 · 07-21-2007, 12:13 PM

Quote:

Originally Posted by MyEclipse5

I'm by myself and I have to hold the tanks line on the boost leak tester so I can't go around feeling for leaks.

I know i know get another person to help, but I work A TON and on my days off most of my friends work.

Next time you do a boost leak test, listen for where it sounds like air is leaking out. Spray soapy water there and then boost leak test again. Since you're by yourself, maybe you'll be able to see the bubbles form where leaks are at while your holding the line to the tester. That, or go make some bum friends who never work

tkelly27 · 07-21-2007, 12:19 PM

Up, up, down, down, left, right, left, right, B, A, start get's you unlimited boost!!1!

If you have a boost leak, stay out of the boost! Your turbo will free spin and that is BAD. I reccomend you go out under your hood and take the actuator arm off of the flapper right this second and leave it off until you are 100% sure you have 0 leaks in your intake tract.

Get a friend, also, you can use a spray bottle with some soapy water. The soap will bubble when squirted on a boost leak. Or you could take it to a shop that has a steam machine, those things are rad as hell.

While a boost leak is the most likely cause, if that turns out not to be the case you need to start looking into the wastegate. A MBC without a spring will still get you to about 10psi on a correctly setup 14b, mine got up to 13psi after my mufflerectomy. Make sure everything is properly attatched, moves freely, moves to where it's supposed to be freely. It could be a bunch of things up in there, but they are all pretty easy to diagnose visually.

Much luck.

MyEclipse5 · 07-21-2007, 01:09 PM

Quote:

Originally Posted by tkelly27

Up, up, down, down, left, right, left, right, B, A, start get's you unlimited boost!!1!

If you have a boost leak, stay out of the boost! Your turbo will free spin and that is BAD. I reccomend you go out under your hood and take the actuator arm off of the flapper right this second and leave it off until you are 100% sure you have 0 leaks in your intake tract.

Get a friend, also, you can use a spray bottle with some soapy water. The soap will bubble when squirted on a boost leak. Or you could take it to a shop that has a steam machine, those things are rad as hell.

While a boost leak is the most likely cause, if that turns out not to be the case you need to start looking into the wastegate. A MBC without a spring will still get you to about 10psi on a correctly setup 14b, mine got up to 13psi after my mufflerectomy. Make sure everything is properly attatched, moves freely, moves to where it's supposed to be freely. It could be a bunch of things up in there, but they are all pretty easy to diagnose visually.

Much luck.

If I take the actuator arm off of the flapper, won't it stay closed all the time? Wouldn't that be bad?

1stGenRocks · 07-21-2007, 01:19 PM

Quote:

Originally Posted by MyEclipse5

If I take the actuator arm off of the flapper, won't it stay closed all the time? Wouldn't that be bad?

no you you unhook the actuator rod from the flapper arm then the exhaust will just blow it open and you wont boost at all

Rob10_99 · 07-21-2007, 01:30 PM

Quote:

Originally Posted by tkelly27

Up, up, down, down, left, right, left, right, B, A, start get's you unlimited boost!!1!

You beat me to it.

romeen · 07-21-2007, 01:35 PM

Quote:

Originally Posted by MyEclipse5

If I take the actuator arm off of the flapper, won't it stay closed all the time? Wouldn't that be bad?

The exact opposite. There will be no resistance holding the flapper shut against the pressure in the turbine housing so you will not be able to boost hardly at all. He is recommending this as a safety precaution until you fix the problem.

Also, if the leak is big then the soapy water will not work. The rushing air simply blows it all out of there. For big leaks llike that you should listen carefully and use your hand to feel for the escaping air. It could definitely be the boost leak tester not making a good seal at the compressor inlet. If you don't have a helper get creative. Tape one end of a strip of paper over each joint (leave the other end hanging loosely) so that you can look for it moving from any escaping air. Again, use common sense and get creative on how you might go about this.

I would recommend starting your leak test from the TB elbow, fix any leaks then move back one section at a time (IC, LICP, etc) fixing the leaks as you go. That way you won't have to deal with as many potential leak areas at one time.

One other thing is to tap either your compressor housing or j-pipe for a nipple to use as your boost source. Whether you stick with a mbc or decide on an EBC you will end up needing this. Let me know if you need instructions on how to go about doing this.