[TDIwyse]

Didn't think I was having overboost issues either, until iaknown showed me that what I thought was measured "actual boost" was not... Verifying what was actually happening with the analog boost gauge and TestO was eye opening... To be fair, Ecotune had warned that running an open exhaust would do this, and that the system was designed to work with some back pressure. Was able to put restriction back in the exhaust to test this, and sure enough it would limit the amount of overboost I measured with the stock internal wastegate. I believe iaknown also did this same type of test (please correct me if I'm wrong on that) and saw similar results.

[35d]

Originally Posted by TDIwyse

Didn't think I was having overboost issues either, until iaknown showed me that what I thought was measured "actual boost" was not... Verifying what was actually happening with the analog boost gauge and TestO was eye opening... To be fair, Ecotune had warned that running an open exhaust would do this, and that the system was designed to work with some back pressure. Was able to put restriction back in the exhaust to test this, and sure enough it would limit the amount of overboost I measured with the stock internal wastegate. I believe iaknown also did this same type of test (please correct me if I'm wrong on that) and saw similar results.

So are you saying that with ecotune dpf off pipe and standard exhaust pipe and muffler you have no overboost?

[35d]

Originally Posted by ajs_335d

I don't seem to have overboost I'm running ecotune remap and dpf delete.

I tune petrols on standalone, of course wg is limiting factor but you can adjust boost tables to effect spool and thus overboost ie manipulating spool, with a 2/3 port boost solenoid you can alter wg duty cycle and error table, however it's a bit of a battle between vicious target boost met or no over spool or sluggish spool, I suspect tables like this exist in the 335d tables.

So are you saying that were the turbo would start to over spool for me higher rpm the ecotune map lowers the requested boost so say for example 1.6 bar and then 0.4 bar is added via the extra overspool due to the extra gasses so keeping the turbo running 2 bar? Or does it not work like that

[TDIwyse]

Originally Posted by 35d

So are you saying that with ecotune dpf off pipe and standard exhaust pipe and muffler you have no overboost?

So, our exhaust system has a urea catalyst for NOx after the downpipe, and between the downpipe and the SCR there's a "mixer" (a fixed bladed fan like thing to spin the air to better "mix" the urea before hitting the SCR). So even after utilizing the ecotune downpipe, there's still extra restriction.

I never accurately measured the real boost with just the remap and downpipe and the normal system in place. The way I had been measuring boost has been proven to be inaccurate. With a fully open exhaust system (downpipe, no "mixer", no SCR, no muffler) the boost, as measured with an anolog boost gauge, was showing ~38psig (~3600 mBar absolute) at the ~2800 rpm point where the big turbo is coming online. Adding a restriction (like putting the "mixer" back in or a blocking plate with a smaller diameter hole) between the downpipe and the rest of the open exhaust, lowered the peak and sustained boost numbers.

Going to an external wastegate allowed me to fully open the exhaust backup without overboosting the turbo.

[Mik325tds]

TDIwyse : Would you recommend leaving the mixer plate in place with a straight downpipe and Jarek's tune?
Or should I take the mixer plate out and drill out the waste gate opening like iaknown?

[35d]

I see I don't know what the mixture system is and what is scr?

We have turbo- catalyst- dpf - exhaust & muffler
The catalyst and dpf is in one box, I left the catalyst in the box and smashed the dpf out

What tool is used to drill the wastegate. I spoke to shops here that make hybrid turbo for these cars for 400hp they said even with those larger turbo they do not port the wastegate. They said you must tune car on dyno and said ecotune does there tune

[iaknown]

Originally Posted by 35d

I see I don't know what the mixture system is and what is scr?

We have turbo- catalyst- dpf - exhaust & muffler
The catalyst and dpf is in one box, I left the catalyst in the box and smashed the dpf out

What tool is used to drill the wastegate. I spoke to shops here that make hybrid turbo for these cars for 400hp they said even with those larger turbo they do not port the wastegate. They said you must tune car on dyno and said ecotune does there tune

To back up what tdi said, Ecotune did state their map wasn't designed for open exhaust. But if the limiters and codes are removed you'd never know if you were overboosting anyway. Sounds like something on your tune is still in place to warn you so that's good.

You mentioned a "serial map" earlier. You mean the stock map? Regardless, 1st off you need to put the wastegate actuator directly to vacuum. Hook a hose to the vacuum line going to it and T into your vacuum source line. Go for a ride and see if you get the code.

You can't compare your car with stock turbos to one with hybrids because the internals are different. Most likely they have clipped/modded wheels that lower drive pressure and lessen overboost.

Best way to open up the wastegate port is using reamers in increments, but its not quite that simple. Especially if you're not familiar with such a mod....

[TDIwyse]

Originally Posted by 35d

I see I don't know what the mixture system is and what is scr?

We have turbo- catalyst- dpf - exhaust & muffler
The catalyst and dpf is in one box, I left the catalyst in the box and smashed the dpf out

What tool is used to drill the wastegate. I spoke to shops here that make hybrid turbo for these cars for 400hp they said even with those larger turbo they do not port the wastegate. They said you must tune car on dyno and said ecotune does there tune

http://www.realoem.com/bmw/showparts...15&hg=18&fg=10

The big section #1 is pointing at is the SCR (NOx catalyst), part #3 is the mixer. We have the same DOC/DPF combination section directly after the turbo as you have.

[35d]

Ok so your issue of overboost is now sorted? Which map do you have

so your solution was an external wastage. Would you say for me it's would be easier to port the oem wastegate?

[35d]

Hi yes serial I was referring to stock map
We're is the wastage actuator on the 286hp engine? On the 272 m57 the actuator you can see but I'm sure the 286hp is on the other side towards engine block so you can't even see it

I do see a vacum line coming from it so that line I should connect were? Somewhere where there is constant vacum so it stays open all the time? Is this the test I need to do. Staying open all the time will that mean no boost is being lost?

Thanks

Originally Posted by iaknown

To back up what tdi said, Ecotune did state their map wasn't designed for open exhaust. But if the limiters and codes are removed you'd never know if you were overboosting anyway. Sounds like something on your tune is still in place to warn you so that's good.

You mentioned a "serial map" earlier. You mean the stock map? Regardless, 1st off you need to put the wastegate actuator directly to vacuum. Hook a hose to the vacuum line going to it and T into your vacuum source line. Go for a ride and see if you get the code.

You can't compare your car with stock turbos to one with hybrids because the internals are different. Most likely they have clipped/modded wheels that lower drive pressure and lessen overboost.

Best way to open up the wastegate port is using reamers in increments, but its not quite that simple. Especially if you're not familiar with such a mod....

[iaknown]

Originally Posted by 35d

Hi yes serial I was referring to stock map
We're is the wastage actuator on the 286hp engine? On the 272 m57 the actuator you can see but I'm sure the 286hp is on the other side towards engine block so you can't even see it

I do see a vacum line coming from it so that line I should connect were? Somewhere where there is constant vacum so it stays open all the time? Is this the test I need to do. Staying open all the time will that mean no boost is being lost?

Thanks

You can't see the actuator on our cars either. Sounds like the same vacuum line. You may need to get under the car to confirm....Connect to constant vacuum which means the wastegate is always open. This will kill your boost down low but will tell you whether your wastegate can get rid of the boost on the topend.

[35d]

Ok I will try that. Do you know where I can get constant boost from? Which hose
Do I have to put a t joint in or can I remove the existing vacum hose from wastegate ?

[9mmkungfu]

Originally Posted by 35d

I see I don't know what the mixture system is and what is scr?

We have turbo- catalyst- dpf - exhaust & muffler
The catalyst and dpf is in one box, I left the catalyst in the box and smashed the dpf out

I don't think the Euro cars had the SCR system w/ mixer.

[35d]

Yes uk cars have no mixer we have turbo then a tin with catalyst and dpf

[iaknown]

Originally Posted by 35d

Ok I will try that. Do you know where I can get constant boost from? Which hose
Do I have to put a t joint in or can I remove the existing vacum hose from wastegate ?

Constant vacuum not boost.....Look for the vacuum distribution under the intake manifold, you will see a few lines from there which feed to all of your turbo controls. You need to tee into one of these lines.

May be better to open up a new thread with your specific issue so we can put this one back on track....

[Yozh]

Originally Posted by iaknown

Constant vacuum not boost.....Look for the vacuum distribution under the intake manifold, you will see a few lines from there which feed to all of your turbo controls. You need to tee into one of these lines.

May be better to open up a new thread with your specific issue so we can put this one back on track....

35d, I have posted in your UK Technical Forum thread.

[35d]

Has anyone got any logs with wastgate constant vacum/open?

Here mine but the car drove no diffrent then when wastgate was not constantly open. Or maybe I didn't feel any diffeence. The graphs do show some under boost low down

This with not direct vacum to wastgate



This 2 logs with constant vacum to wastegate




Anyone got issue is you can't see wastgate actuator but if I give direct vacum it holds pressure but when release back you can't hear the valve click back. If I could see it moving it would be better

[iaknown]

Originally Posted by 35d

Anyone got issue is you can't see wastgate actuator but if I give direct vacum it holds pressure but when release back you can't hear the valve click back. If I could see it moving it would be better

Graphs are too close together to see anything. Can you regraph with the readings spread out?

Purchase a cheap usb camera with built-in light, get under the car and attach it to point at the actuator. Around the steering rack works good. Go for a drive and record it so you don't drive off the road At idle you will only see the actuator move a little so you cannot verify that way. Under full load, higher rpm will make more vacuum and turbine pressure will also help open the actuator. Do this first instead of wasting too much time on logging.

[Yozh]

Did you check your vacuum pump. You had mentioned to me that all your actuators were dead.

[DWR]

I'm seeing differences between the sets of graphs. That first one is interesting because you are over the targeted boost at both high and low boost pressures. That graph also records the highest max of the set. Then you apply direct vacuum and you don't hit that highest level again, even though there is more data. And at low boost pressures you seem to follow the target better. My first guess would be a vacuum leak somewhere.

[35d]

How can I plot the graph weigh readings more apart?
I think testo logs in less then 1 sec intervals

Yozh my loss of vacum to both turbos was fixed with a new pressure converter.

[pheno]

Megalogviewer free version shows nicely Testo's .csv log files. You could try that