InlineTwin
Member
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- Mazdaspeed6
So, you did not install a boost cut killer initially?
3076R Install
- Thread starter chriscecc914
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So, you did not install a boost cut killer initially?
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- MP5T / 944
So... Just like the MSP
"Mazda Turbo, The Perfect Tuning Cars If You Leave Them STOCK"
"Mazda Turbo, The Perfect Tuning Cars If You Leave Them STOCK"
forrestang
Member
Nope.....didn't have fuel cut either with the stock airbox on there. I did install one eventually cause I was trying to run an open filter element which caused fuel cut.
leakslikasieve
Member
wow man that sucks. sorry to hear. i don't want to down you, just some constructive criticism. why did you install a turbo 2 times the size of stock without a boost gauge at minimum? again sorry for the temporary loss. was it a rod or a rod bolt that caused the failure.
InlineTwin
Member
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- Mazdaspeed6
The air box is a different issue. Not having the fuel cut mod allows the ECU to keep everything working order. It would not matter what your WGA was set to (within reason).
I get the impression that more than a well determined decision to install the mods in the order you did you were fortunate to have done so in that order.
Without a boost controller set properly the elimination of the ECU boost control the engine will continue to let the actual boost rise. The fuel cut killer lies to the ECU by allowing pressurized air to escape near the map sensor. This creates a localized pressure of 15.5 psi. The ECU will not know what the actual pressure is and will assume the WGA does not need to be opened. It does not matter what the WGA is set to, you will over boost and blow the engine.
Not to get on a soap box, but this is fairly introductory stuff. If you are not sure, do more research or pay a shop you trust to do the work. (hand)
forrestang
Member
I think you're wrong here on many accounts. Many people have had fuel cut on a stock speed, with nothing but a CAI. I think the reason is that the MAF housing and transitions are throwing off people's fuel trims.
Fuel cut is caused by more than boost. If it were simply a matter of boost....that fuel cut killer would have solved everyone's problems, but it didn't. Fuel cut is not simply a matter of boost pressure in the manifold.
I can almost guarantee that no matter what you do to you car, if you keep the stock airbox on there....95% of the time you will not have fuel cut, no matter what you boost to.
If this guy did install his turbo in the recommended order, the factory BC was not in the loop. The way you control boost, if you do not have a BC of some sort after you install the Garret, is by hooking a pressure source directly to a WGA. I think you are confusing some things here?
The engine has nothing to do with the developement of boost pressure. The fuel cut killer has nothing to do with developement of boost pressure that the turbo produces. If you plumb your WGA direct to pressure source, whenever your turbo outputs the refference psi to the WGA, the wastegate will open. It's that simple. I know this because I've done it this way.
I think your forgetting what a WGA does? Think about it very simply. The WGA is nothing but a valve that opens when it sees a certain psi, that's it, nothing more. The WG on the turbo opens, bleeds off exhaust gases from the turbine, and the turbo slows down.
It doesn't have anything to do with a BC, or the engine, or anything. They are all calibrated for a certain psi. A BC, electronic or manual simply bleeds some of the reference psi off, so that the WGA does not see the reference until you want it to. That's all. If you don't have a BC, and have the Garret, if you plumb it the way I mentioned it above, when the turbo produces the reference(15psi from ATP), it opens, and does this over and over to maintain the boost reference.
If you need to?
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InlineTwin
Member
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- Mazdaspeed6
You (I do mean YOU this time, see below) really don't know how this engine works...Period. Dont' confuse one issue with another and you will figure it out, I'm sure.
Don't take the previous post personally I meant 'You' in the general sense of anyone affected by such incompetence...
Its not that he doesn't know how an engine works, its just that you don't know enough about the MS6 and related problems we have been having with it. For some reason this car and its ECU/DISI seems to be a lot more involved than everyone thought it would be. Every thing that Forrest has stated is true about the Speed6, I wish you would tell us what part of his statement you do not think is right, Twin.
forrestang
Member
Nothing wrong with someone disagreeing with me. But, please tell me which part of my previous post was incorrect?
I'm not above learning somehting new!
InlineTwin
Member
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- Mazdaspeed6
I personally like to by righteous and lazy than right and informative. I am not willing to write a 10 page white paper on the vacuum system and its interaction with the ECU in relationship to the throttle position, MAF, MAP, and timing. (although that is a great title for such a paper)
The fuel cut killer (really boost cut) is a bleed valve that controls the local pressure around the MAP sensor to 15.5 psi. So no matter what was actually being pumped in to the engine the ecu would think it was 15.5 psi and do its normal thing for that pressure, which does include interactions with the timing, MAF, knock, throttle position etc. Lying to the ecu about just the boost pressure is not a good idea if you do not supplement it with a boost controller that is set to a boost range the ecu can compensate for and continue to control all the other factors.
Fuel cut killer does not actually control fuel. You are completely correct, but you are arguing against a different matter entirely. Don't get lost in what you know... and stay focused on the discussion.
???
In the case the WGA is directly tied to MAP, yes the WGA will respond accordingly. IF this is how he plumbed it then it would seem an experiment is required. Test articles: Regulated air compressor and his WGA. Plumb it up and see how much pressure it takes to crack the WGA and also to open the WGA about 30%. This would give a good idea of where the WGA was set and how much boost he was pushing before the failure.
Think about my prevous post very simply and try not to get ahead of yourself.
Understand this: if you plumb your big bad ass turbo into the stock vacuum lines the ECU has control of your WGA. The ecu will only pulse enough pressure in to the line to control the boost at stock levels. If you bypass or trick the sensor that the ECU gets it's pressure info from, like installing said fuel cut killer, you will inevitably have an completely uncontrolled boost condition since the ECU thinks everything is fine, 15.5 psi in the manifold! It will not pulse enough pressurized air to the WGA to open it and let the ridiculous 30 psi actually in the manifold decrease.
Now the BOV comes into effect here as well. I can't state how this impacts his actual boost since I don't know if he has the stocker or not.
The fuel cut killer (really boost cut) is a bleed valve that controls the local pressure around the MAP sensor to 15.5 psi. So no matter what was actually being pumped in to the engine the ecu would think it was 15.5 psi and do its normal thing for that pressure, which does include interactions with the timing, MAF, knock, throttle position etc. Lying to the ecu about just the boost pressure is not a good idea if you do not supplement it with a boost controller that is set to a boost range the ecu can compensate for and continue to control all the other factors.
Fuel cut killer does not actually control fuel. You are completely correct, but you are arguing against a different matter entirely. Don't get lost in what you know... and stay focused on the discussion.
???
I am supposing he tied the WGA back into the vacuum lines exactly as the stock turbo was plumbed. This would put the WGA completely under the ECU's control. Since the boost pressure will never exceed 15.5 psi as the ECU sees it, it would not have reason to open the WGA if the driver is commanding a 75% throttle position at 4000 RPM. The ECU may try to pull timing and throttle position when it detects knock; I don't know if it would have tried to dump boost. My estimation is that it would, but would be unable to open the WGA enough to let all the excess boost off that it did not know was present.
In the case the WGA is directly tied to MAP, yes the WGA will respond accordingly. IF this is how he plumbed it then it would seem an experiment is required. Test articles: Regulated air compressor and his WGA. Plumb it up and see how much pressure it takes to crack the WGA and also to open the WGA about 30%. This would give a good idea of where the WGA was set and how much boost he was pushing before the failure.
(jaw slightly ajar, quietly drooling on myself...)
Think about my prevous post very simply and try not to get ahead of yourself.
That is an assumption about the supplier set WGA. I would not trust such a claim of a pre-set WGA; that is for nubes who blow up thier engines. (calibrated...phsst)
Understand this: if you plumb your big bad ass turbo into the stock vacuum lines the ECU has control of your WGA. The ecu will only pulse enough pressure in to the line to control the boost at stock levels. If you bypass or trick the sensor that the ECU gets it's pressure info from, like installing said fuel cut killer, you will inevitably have an completely uncontrolled boost condition since the ECU thinks everything is fine, 15.5 psi in the manifold! It will not pulse enough pressurized air to the WGA to open it and let the ridiculous 30 psi actually in the manifold decrease.
Now the BOV comes into effect here as well. I can't state how this impacts his actual boost since I don't know if he has the stocker or not.
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forrestang
Member
So.....as JB said prior, I don't think you know how this kit is installed?
I never said it did control fuel. I have ATP's FCD, I actually checked it with a hand pump before I installed it. I know what it does. My point about the airbox was that fuel cut is not simply a function of boost in the manifold.
If this were the case, ATPs fuel cut killer would have resolved all fuel cut issues, but it didn't. As there were people with this FCD isntalled that still had fuel cut problems.
So I was correct in my previous statement, that the ECU, throttle plate, HAS NOTHING TO DO WITH THE BOOST PRESSURE THE TURBO WAS PRODUCING. He did not have his vacuum plumbed that way. They were completely out of the loop.
And this is what i've been saying this entire thread. You guys are talking about the turbo kit, but don't even know how its connected.
As JB said previously....."its just that you don't know enough about the MS6 and related problems we have been having with it. "
I don't mean that in an insulting manner, as you obviously understand a bit about the car in general, but we are talking specifically about the turbo upgrade, as we've all pretty much hooked it up the same way.
Admittedly, it won't take into account timing, IAT temp, knock, or any other safety factors, but it will self regulate its boost pressure.
I know the two things you need to do to the factory system to get the factory BC to control your boost with the upgraded turbo, as I've done it already, and know I do it with my laptop by dialing it in. It was a bit of trial and error with logging, but it works well.
Sure, no disagreements there.
???
I never said it did control fuel. I have ATP's FCD, I actually checked it with a hand pump before I installed it. I know what it does. My point about the airbox was that fuel cut is not simply a function of boost in the manifold.
If this were the case, ATPs fuel cut killer would have resolved all fuel cut issues, but it didn't. As there were people with this FCD isntalled that still had fuel cut problems.
As I said before numerous times, HE HAD THE PRESSURE SOURCE CONNECTED DIRECTLY TO THE WGA!!!!!
So I was correct in my previous statement, that the ECU, throttle plate, HAS NOTHING TO DO WITH THE BOOST PRESSURE THE TURBO WAS PRODUCING. He did not have his vacuum plumbed that way. They were completely out of the loop.
And this is what i've been saying this entire thread. You guys are talking about the turbo kit, but don't even know how its connected.
As JB said previously....."its just that you don't know enough about the MS6 and related problems we have been having with it. "
I don't mean that in an insulting manner, as you obviously understand a bit about the car in general, but we are talking specifically about the turbo upgrade, as we've all pretty much hooked it up the same way.
This is not how he plumbed it.
I'm sure I don't need to say it again, but the system wasn't hooked up that way. The ECU is not controlling boost. While this isn't necessarily the safest/smartest thing to do....you can have the turbo and WGA self regulate itself by hooking the pressure source to the WGA on the Garret.
Admittedly, it won't take into account timing, IAT temp, knock, or any other safety factors, but it will self regulate its boost pressure.
I know the two things you need to do to the factory system to get the factory BC to control your boost with the upgraded turbo, as I've done it already, and know I do it with my laptop by dialing it in. It was a bit of trial and error with logging, but it works well.
Wanna bet? Its called to much timing and not enough fuel! Lean condiition. Lightnings do it all day long with bad tunes and those rods exit hard left out of a cast iron block!
What he needs to do is pull the plugs for us. I want to see what they look like. I think he ran out of fuel myself... A rod doesnt snap unless there is some serious detonation going on.. Enough to make that rod shake like jello.
These cars are so new, people have going to have ugly experiences. Instead of sitting here and taunting this guy, this is the time for learning. The last thing i want to hear are people telling each other its ok to slap on a massive turbo without a tune. Thats nuts and completely asinine advice.. IF youre going down this route with the ATP, what is $75 for 3 pulls on the dyno to assure your afr is ok? Every car is different, period.
I betcha, throw in stronger forged rods, leave everything alone and he snaps a rod again. Its the tune people and if you want to sit there and deny it, so be it, but a rod doesnt snap because its weak... Detonation causes rod failure. Low oil causes rod bearing failure , which causes the engine to cease. 2 totally different conditions.
forrestang
Member
You are correct in you statement as to what can cause a rod failure.
Every car is different sure. And it's wise to at least monitor your engine after modding. But anyone that has actually installed an aftermarket turbo on this car, and monitored A/F, this car is no where near lean. The A/F on this car with stock tune dips down in the mid to high 9s. At least it was on my car and every other Speed I've seen on the dyno with a stock tune.
This car is not running lean. And I believe the car will run out of fuel eventually as seen on my injector logs in my other post......but it ain't happening at 4000rpm as the original poster's motor let loose.
it can happen at 4k if hes running too much boost. but theres no way to tell what he was running since he didnt have the gauge. so this whole thread is really just speculation and no one will ever know what happened cause there was no way to monitor it.
its funny how our msps are tuned the exact same way. well its not really funny. its dumb but what can u do.
its funny how our msps are tuned the exact same way. well its not really funny. its dumb but what can u do.
forrestang
Member
I concur.
Unfortunately, none of us were there to help install so nobody knows if it was isntalled correctly?
gerasimatos
Member
Wow, some people need to go back to school. Boost pressure should be measured at the manifold and regardless of the turbo size, 18psi = 18psi.... You should read Corky Bell's book Maximum Boost. Here is a link for some good reading
http://www.stealth316.com/2-turboguide.htm
There is a difference when you look at PSI versus CFM... 18 PSI is 18 PSI, HOWEVER, 18 PSI at 800CFM is much different than 18 PSI at 2000 CFM... I believe this is what he is trying to tell you.
InlineTwin
Member
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- Mazdaspeed6
Correct and both of those are out of this little 2.3L engines' capability under most circumstances.
It is a preference, but I like lb/min. It is easier to work with mass air flow IMHO.
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