My 20v 2.5 stroker track day ur quattro

[AndyP]

@Damo

How have you confirmed that the engine really is 7.6:1?

[prj]

If it can run 19 deg in the middle at 1.7 bar, it's certainly low CR.
But it also means it should love boost...

There is either a flow choke issue, or whoever mapped it pulled too much timing out or added too much fuel.
But I can't comment on that without logs.

[DamoM]

While water meth is good, with a 7.6 CR there's deffo something else going on...

Also, if you use meth injection without a failsafe, you can not map specifically for it, only use it in small amounts...

Because if something happens to your meth kit you are gonna melt your engine otherwise. That's the main thing why I use Aquamist on everything.
Don't get me wrong, any meth injection system is going to result in massively lower IAT's, better cylinder filling and more power. But I think in this case it won't do much...

My car runs aquamist but I think you suffer from the same issue with the water running out or the pump failing? (I've had 2 fail).

[DamoM]

@Damo

How have you confirmed that the engine really is 7.6:1?

We measured it with fluid and pipets! pretty sure it's about right.

[DamoM]

Andy, I doubt you have 10:1 CR...
Stock is around 9.

Regardless - this is all speculation here without proper logs.
Shouldn't be that hard to make with a standalone ECU

My reply was prompted by "I don't see how people make more than xxx power" - and the answer is, they run more boost. For 1.7 bar your results are as expected. If you're running it flat though, then you're missing out as this is not a top end turbo.

I'm pretty sure we have the logs. The ecu is set to record constantly so you always have an amount of data going back in case of problems.

I appreciate your reply but have yet to see any plots. The car on your link is on a different level engine-wise to mine so hard to make a comparison.

What do you mean by running it flat?

I chose this turbo as the car is a track car so I compromised between lag and power.

[DamoM]

It's never been on a dyno, but according to Vas's Racelogic performance box, it's got around 320whp.

I have a performance box. It said my RS4 had 760+ bhp when I knew it had less than 600 bhp at the time. I love them for track and acceleration timing but noi for bhp estimates.

[DamoM]

Well, I just posted a dyno plot of someone making way more power and torque than you at 38 psi on a higher compression ratio than you on a 2.5 stroker.
According to your logic his engine should be in pieces and running anything more than 25 psi is impossible.
Sorry, but what you write does not line up with the 100 odd I5's I've mapped, that's all.

No. What I am saying is that my engine was detonating at higher boost. I'm not intending to apply my logic on anyone else's engines, simply relaying what happened to my engine when we dialled in more boost....big difference.

[DamoM]

If it can run 19 deg in the middle at 1.7 bar, it's certainly low CR.
But it also means it should love boost...

There is either a flow choke issue, or whoever mapped it pulled too much timing out or added too much fuel.
But I can't comment on that without logs.

Out of those options I guess flow choke is the most likely. I need to work out how to measure this..

[A80Avant]

I have a performance box. It said my RS4 had 760+ bhp when I knew it had less than 600 bhp at the time. I love them for track and acceleration timing but noi for bhp estimates.

We are not using the performance box actual estimation for bhp. I have 2 different excel spreadsheets I use from.its data and they are very accurate to the point where the dunk dynamics operator was amazed

[DamoM]

We are not using the performance box actual estimation for bhp. I have 2 different excel spreadsheets I use from.its data and they are very accurate to the point where the dunk dynamics operator was amazed

That's very interesting. What gear do you measure in?

[A80Avant]

Usually 3d or 4th. But with a simple method I can measure 5th if we are on a track

[DamoM]

Usually 3d or 4th. But with a simple method I can measure 5th if we are on a track

I want that spreadsheet!! Ha ha

[prj]

My car runs aquamist but I think you suffer from the same issue with the water running out or the pump failing? (I've had 2 fail).

You have water/meth as well? Then your numbers are deffo too low.
HFS-3 has a failsafe with a flow sensor. When properly installed this is wired into the ECU, so the ECU switches maps if there are any issues with the flow.

I don't see how the car I posted is "on a different level engine wise". It is a diesel block stroker and it's compression ratio is higher than yours. So it's break-even point boost wise is lower.

But it's okay, I'll just drop it.

[DamoM]

You have water/meth as well? Then your numbers are deffo too low.
HFS-3 has a failsafe with a flow sensor. When properly installed this is wired into the ECU, so the ECU switches maps if there are any issues with the flow.

I don't see how the car I posted is "on a different level engine wise". It is a diesel block stroker and it's compression ratio is higher than yours. So it's break-even point boost wise is lower.

But it's okay, I'll just drop it.

My aquamist is a basic water only one. Can't remember the model.

[DamoM]

Andy, I doubt you have 10:1 CR...
Stock is around 9.

Regardless - this is all speculation here without proper logs.
Shouldn't be that hard to make with a standalone ECU

My reply was prompted by "I don't see how people make more than xxx power" - and the answer is, they run more boost. For 1.7 bar your results are as expected. If you're running it flat though, then you're missing out as this is not a top end turbo.

Dmitri. what are you looking for from a log that you can't see on a plot? It does have logging but I'm not sure what to record!