Strange Behaviour

[parso_rex]

DP diameter is not going to cause that issue and 2.5" is more than adequate for the stock turbo but yes a 3" tapering to 2.5" (or 2.25" is ideal). If you have no leaks and everything else is mechanically sound then it would appear that the set duty cycle is too low for the turbo to produce enough boost reach the specified target but there's so many other things that need to be modified in the file that could cause the same thing.
Do your logs in 4th gear 3K rpm to redline and post it up that's all you need to do (apart from find a nice bit of M4/M5 )

Mark

[parso_rex]

not a nice colour for an exhaust to be either, looks like its been very hot under there .........

[pinkgti]

DP diameter is not going to cause that issue and 2.5" is more than adequate for the stock turbo but yes a 3" tapering to 2.5" (or 2.25" is ideal). If you have no leaks and everything else is mechanically sound then it would appear that the set duty cycle is too low for the turbo to produce enough boost reach the specified target but there's so many other things that need to be modified in the file that could cause the same thing.
Do your logs in 4th gear 3K rpm to redline and post it up that's all you need to do (apart from find a nice bit of M4/M5 )

Mark

Thanks Mark,

I'll start with matching tune file and DP to eliminate this first. It's meant to have 3" going to 2.5" to match the stock muffler.

Sounds like the guys bolting the hardware on weren't talking to the software guys or something. Anyway I'll get this sorted first and then go from there.

Anyone have a favoured section of road? I'm guessing flat and do a few runs plus leave a good few minutes between each to let temps get back to "normal"?

[h100vw]

Thanks Mark,

Anyone have a favoured section of road? I'm guessing flat and do a few runs plus leave a good few minutes between each to let temps get back to "normal"?

After a bit of a coast down and by the time you have changed the blocks on the laptop, it'll have recovered.

Gavin

[pinkgti]

After a bit of a coast down and by the time you have changed the blocks on the laptop, it'll have recovered.

Gavin

So which blocks do you usually log? There's quite a few to choose from and often parameters are repeated between blocks.

I imagine you recommend only do 1 block (4 parameters) at a time on turbo so you get the greatest resolution?

Sorry this info is probably on other threads - should do some more trawling....

[pinkgti]

not a nice colour for an exhaust to be either, looks like its been very hot under there .........

What's "normal" then?

Should the section after the cat be nice and shiny silver still?

[h100vw]

So which blocks do you usually log? There's quite a few to choose from and often parameters are repeated between blocks.

I imagine you recommend only do 1 block (4 parameters) at a time on turbo so you get the greatest resolution?

Sorry this info is probably on other threads - should do some more trawling....

Finding the right blocks in that ECU is painful. Only done a couple, a useful set below. See if you can find a couple of other ones that mention rail pressure, I think it is deviation?

rpm - requested boost - actual boost - absolute engine load - wastegate duty cycle
rpm - ignition angle - throttle valve position - retarding cyl 1 - retarding cyl 2 - retarding cyl 3 - retarding cyl 4
rpm - injection time - air mass - absolute engine load - actual lambda - desired lambda - lambda correction
rpm- the rail pressure ones

Gavin

[AdamD]

This page may be of some help in terms of deciding what to log:

APR - High Performance Development for Audi, VW and Porsche Vehicles.

[pinkgti]

This page may be of some help in terms of deciding what to log:

APR - High Performance Development for Audi, VW and Porsche Vehicles.

Thanks forth link Adam. When I get the new exhaust on I'll try these out.

I'm hoping the change from 2.5" to 3" exhaust (to match the tune) fixes 90% of the issues.

[Lucas_R]

What's "normal" then?

Should the section after the cat be nice and shiny silver still?

In the first 20-30cm of the dump pipe (where its hottest straight out of the turbo) its quite normal to have some purple colour amongst the deep copper/gold colour of the pipe.

Over the next 50-70cm of pipe, very deep golden / copper colour is normal where its still quite hot. From here onwards, a lighter golden/copper colour usually carries on for the rest of the downpipe as the gasses aren't as hot by now.

Given yours is quite blue/purple in colour and this is even further down the exhaust near the catalic convertor etc, id say its been extremely hot. i don't think the change from 2.5inch to 3 inch on the dump pipe will make much of a difference to the issues you are reporting, as i think there is something up with the engine/tuning which is causing the issues you are describing - although i'd be happy to be proven wrong.

Have you logged your Lambda values? Because if the engine is running excessively lean (too much air and not enough fuel) then this can make the engine and exhaust very hot (not good).

PS - is the tuner local within Australia, or are you dealing with someone overseas? Who is the tuner?

[parso_rex]

What's "normal" then?

Should the section after the cat be nice and shiny silver still?

Not shiny just tarnished. The weird thing is the dump looks OK. It could be one of those thin walled deliberately coloured systems that you can get from China. The welds and that look pretty average but are probably OK. Watch the clearance with the shift cables especially when you upsize to a 3" system
Log measuring blocks
20
31
115
together to improve your sample rate and also it will give you most of the info you need initially.

[pinkgti]

OK DP photo I posted before was an older photo I had taken soon after installation. Here's a current shot of the DP:



Certainly a lot more blue now.

[parso_rex]

Get it checked before you kill it. It may be perfectly fine but just going off the above info which is very hard to do from a couple of posts on the internet something seems 'very odd' - note that I'm in a very kind frame of mind atm
If those boost plots are accurate I would not have let the car leave our workshop it needs alot more work

[pinkgti]

Get it checked before you kill it. It may be perfectly fine but just going off the above info which is very hard to do from a couple of posts on the internet something seems 'very odd' - note that I'm in a very kind frame of mind atm
If those boost plots are accurate I would not have let the car leave our workshop it needs a lot more work

Right so hot engine + hot turbo = short life (....and no more pink GTI)

Is that what you're trying to tell me? Will definitely get it checked but just wondering how much more I should drive it in current condition (I'm guessing as little as possible).

[Transporter]

Just don't push it at all and get it sorted ASAP.