Project: RS2 ABY

[A80Avant]

in danger of initiating yet another flamboyant post from the known suspects, i have to say, i have never experienced this issue after my motronic was switched off.

mac valve and aftermarket ECU has never EVER had issues on this aspect. And im pretty sure its not a mechanical issue, otherwise Brian Tonks will be looking to be fully booked for 2013.!!

Hope you get it sorted soon Andy!

[Rocco]

in danger of initiating yet another flamboyant post from the known suspects, i have to say, i have never experienced this issue after my motronic was switched off.

mac valve and aftermarket ECU has never EVER had issues on this aspect. And im pretty sure its not a mechanical issue, otherwise Brian Tonks will be looking to be fully booked for 2013.!!

Hope you get it sorted soon Andy!

Vas, i have to test without DV... and see what happens.

the car holds alll the boost perfectly in any gear but the problem appears when you shift hard in the top revs.


i have the same issue now with the race engine,it seems to be happen with 3 to 4 gears or higher.

but it happened to me the same when i had the old 3B engine with other wastegate and other DV with the k26/27.


my friend Simons is having the same issue with his k26/27 and 007P DV

and Sonic also..... this is why i wanted to ask him about...to try solving the problem
because it looks the same

[prj]

Andy, if you remember, your boost is limited until a certain RPM to about 1-1.5 bar due to the surging issue.
When you are changing gear, are you sure you are changing into the area that is not limited to prevent surge?

You are one of the few who has this issue, as I've never had this problem on cars that are much more powerful than yours.
I'll be over in the UK this year. I can take a look at it from the ECU side if you like, but I am pretty sure that I will find the N75 duty cycle at 100% after the gear change...

Vas, i have to test without DV... and see what happens.

the car holds alll the boost perfectly in any gear but the problem appears when you shift hard in the top revs.


i have the same issue now with the race engine,it seems to be happen with 3 to 4 gears or higher.

but it happened to me the same when i had the old 3B engine with other wastegate and other DV with the k26/27.


my friend Simons is having the same issue with his k26/27 and 007P DV

and Sonic also..... this is why i wanted to ask him about...to try solving the problem
because it looks the same

Your "race" engine has been lifted from one car to the other, where there was absolutely no problem with this, and now the problem appeared, so I am 100% sure in your case this has nothing to do with the ECU management.

I believe you sat next to me, when I drove the crap out of that car after being done with mapping it, through the gears, and there was no such issues. I even remember you screaming "what are you doing, this is dangerous". Do you remember?

As for Simons car - no idea about that one, but it is not even tuned yet.

[A80Avant]

im using APR R1 DVs but dont know if its a DV problem

[A80Avant]

Andy, if you remember, your boost is limited until a certain RPM to about 1-1.5 bar due to the surging issue.
When you are changing gear, are you sure you are changing into the area that is not limited to prevent surge?

You are one of the few who has this issue, as I've never had this problem on cars that are much more powerful than yours.
I'll be over in the UK this year. I can take a look at it from the ECU side if you like, but I am pretty sure that I will find the N75 duty cycle at 100% after the gear change...

now that is a perfectly plausible reason why it could be doing what is doing!

how come the K26/27 are surging? i thought this was a garrett problem mainly!

[prj]

now that is a perfectly plausible reason why it could be doing what is doing!

how come the K26/27 are surging? i thought this was a garrett problem mainly!

Sonic has no K26/K27 I have ever seen. That turbo runs about the same boost like a 0.82 A/R GT30R.
And it does surge. I think maybe the turbine housing A/R is quite small.

So until 4000 RPM the boost is limited like this:
2500 1.3
3000 1.4
3500 1.65
4000 2.25

And the base duty cycle as well:
2500 98%
3000 25%
3500 34%
4000 50%

The gap at 3000 and 3500 is there to prevent surge.
So if you shift right into that area, the turbo won't make much boost for a moment, else it would surge, and as the revs increase it comes on boost again.

[Rocco]

Andy, if you remember, your boost is limited until a certain RPM to about 1-1.5 bar due to the surging issue.
When you are changing gear, are you sure you are changing into the area that is not limited to prevent surge?

You are one of the few who has this issue, as I've never had this problem on cars that are much more powerful than yours.
I'll be over in the UK this year. I can take a look at it from the ECU side if you like, but I am pretty sure that I will find the N75 duty cycle at 100% after the gear change...



Your "race" engine has been lifted from one car to the other, where there was absolutely no problem with this, and now the problem appeared, so I am 100% sure in your case this has nothing to do with the ECU management.

I believe you sat next to me, when I drove the crap out of that car after being done with mapping it, through the gears, and there was no such issues. I even remember you screaming "what are you doing, this is dangerous". Do you remember?

As for Simons car - no idea about that one, but it is not even tuned yet.

Yeah,true, this is why I want to know what happens with my DV,wastegate or any other thing.
I'm fixing it few to few

You always drive too fast...

[Sonic]

Andy, if you remember, your boost is limited until a certain RPM to about 1-1.5 bar due to the surging issue.
When you are changing gear, are you sure you are changing into the area that is not limited to prevent surge?

Certain.

It only seems to happen when you shift near redline, like 6500rpm+, which wouldn't drop you anywhere near boost-restricted rev-range in the gear below.

Also, even if it were dropping <4krpm it would still be producing >1bar, whereas it seems to sit at 1bar before jumping to target boost.

It feels much like i'd expect a DV piston sticking to feel like or similar, also it is intermittent.

Just knocked this together to hopefully demonstrate the problem, take a good look at the rev counter and boost gauge (uploaded in 1080p so visible full screen), you'll see/hear it sticking at 1bar for a second just after the gear change.

[Sonic]

now that is a perfectly plausible reason why it could be doing what is doing!

how come the K26/27 are surging? i thought this was a garrett problem mainly!

I'm running a kx500 with 2.2bar from 4krpm.

[Rocco]

Andy,do you have a recent picture of your engine bay with the new coils?

What kind of spark plugs are you using now?

[Sonic]

You can kind of see them in a photo somebody took at ADI



The rocker-cover slots back on in 30 seconds if needs be which is nice.

Pretty certain spark plugs are your usual bosch F5DPOR.

[prj]

The fact that it is intermittent is already telling me it can not have anything to do with the ECU.

The ECU is a pretty simple animal. If you do the exact same thing multiple times in a row and can reproduce the issue exactly, yep it's the ECU.
If however you can't every time, then the ECU can not be the issue.

I am not saying this is not electrical. Have you checked all the wiring to the N75?
Is the N75 okay? From the mechanical POV - could the wastegate be sticking?

There are two things that happen:
a) The whole drivetrain rocks as you go off the power and back on the power, so if there is a bad electrical connection it is likely to be disturbed during this time.
b) The EGT's rise, and that heats up the wastegate. So if it has too close tolerances, then it might be seizing.

Try also disconnecting the MFTS temporarily, maybe a bad contact is causing that to go off and send a signal to the ECU to reduce the boost?
Just a few ideas

[Sonic]

DV, N75, WG... all things Will'll be looking into

I dont think it's ECU related either.

[driftin jo]

Mine used to do this and it was the DV sticking open,
I took it apart cleaned it and put some moly grease
thinned down with some WD40 in it and it has been fine ever
since.

[Sonic]

Yeah that's exactly the kind of thing i'm expecting and hoping it is.