NefMoto

Hi!
I am having some problems with low power increases and timing retardation kicking in too early.
It does around 260g/s of airflow with up to 1.6bar boost.
Please find the logs. Do you see anything suspicious that could potentially cause the timing to retard and prevent power output from increasing?

Setup:
1.8t AUQ
630cc Bosch injectors
4bar FPR
3" MAF
Sytec 300l/h fuel pump
K04-064 - TTE480

Logs attached

Fuel not mentioned, compression ratio not mentioned.

How do you think anyone is going to be able to tell you anything?

Thanks for pointing this out.

CR was only affected by using BAM pistons.
Fuel is 98-octane E5.

Let me know if anything else needs to be clarified.

BAM pistons are not for a small port head...
So who knows what compression ratio you are actually running.

From the looks of it, way too high. You're done.
You need to run the car on ethanol or build the engine with a reasonable compression ratio for your power target. 9.5:1 or 10:1 is not it.

8:1 pistons are more like it on small port head... 8.5:1 on a big port head.

BAM is small port head.

BAM pistons are 9:1 in the BAM engine.

IMO 9:1 is high for 1.6bar+ if you wanna get decent timing out of it on pump fuel..

Yes you are right of course, I have no idea what I was thinking when writing the post.
But anyway CR is too high for power target. And if you want to run over 1.5 bar boost you need forged rods as well, stock stuff turns into bananas after that...

in this log you are doing ~240g/s with 1,3 bar of boost and timing goes from 6 to 14 degree during spool

tbh, you can lower boost and add more timing, will result in lower egt, less stress on turbo and same airflow, you'd be in better point of compressor map

Also can set more sane lambda, at around 0.8-0.81, that will make more power too.
This will make around 290-300hp.

"But it's a TTE480" - well if you want to make more power you need engine with correct compression ratio for the fuel and turbo that you chose.
Also intercooler could use an upgrade.

http://nefariousmotorsports.com/forum/index.php?topic=22084.msg161742#msg161742

Check out this post and change your lamfa during spoolup. This made a big difference for me with a similar turbo size.

I have checked the boost presure supposing that  intercooler might be the main reason.
The pressure was 2bar before the intercooler, and 1.6bar after.
What do you Think about it? The delta pressure seems to high and may potentially cause some backpressure.

Bar and Plate or Fin and Tube?
Which Car and which intercooler is this?

Are you running some kind of 5120hack or just bigger sensor because your boost is /2 ?

Your current boost and maf is more like a stock k04-064.

If your boost drop over the intercooler is too high you are pushing the turbo out of its compressor map but you will see only small boost @ the mapsensor.
In your case i dont see a big problem at the moment because your boost is reasonable compared to the low wgdc.

Bar and plate. One sided (this makes me wonder if there is enough flow)
Yes, I am running the 5120 hack with bigger sensor.

So what do you think about the pressure drop values over the intercooler?
Isnt it too high?

With one sided you mean its a fmic but with inlet and outlet on the same side?
this is shit

Sounds completely normal to me. Remember that the air gets cooled down in the intercooler.

20% delta is completely normal, when you get closer to 35% then you have a problem.

Your problem is high compression ratio and then intercooler will make problems later when you increase boost.
Not flow wise, just it does not seem to cool that well.

But this is like 1% of the problem right now and not worth talking about. The high CR is the main issue.
Either rebuild the engine, fit CR lowering headgasket (not ideal) or fit WMI, or convert to E85. No other way around it.
If your rods are stock, then you are gonna have to rebuild it anyway.

Update: I lowered the boost yesterday to 1.5 bar, so it  does  around 310hp/430Nm and  at least puts less stress to the turbo. Nevertheless I will replace the cooler first as I will have to do this sooner or later as the ambient temperatures get higher.

I totally get the idea of reducing the compression ratio too, I will think of what would be the best way to do so. Do you have any idea about the proper head gasket to fit in? Or should I use the spacer?

Ps
I already have forged rods.

Update.
I have replaced the old shitty onesided intercooler with two-side 600x300 one, and placed the new BAM intake manifold.
It has made a slight difference in airflow at higher rpm range but CFs stayed at the same levels.
Please find the new logs attached
I get the idea of reducing the CR, but it seems to be worth the deal when trying to get over 370-380HP, not past 320HP.
I have seen some projects doing more than 360HP with 9.0:1 CR, so I am afraid that there is another problems.
What do you think?

You were already told what the problem is.
If you choose to ignore that and believe in fairytales then that's on you.

Your CR is probably even higher because the head was off the car and most likely was skimmed.
Certainly when building the engine you never measured the actual chamber sizes by filling with liquid, so you have no idea what your real CR is.

You can either keep the boost at 1.5 bar or you can:
a) Drop CR
b) Increase quality of fuel - WMI, race fuel, octane booster, E85 - pick one.

We have seen guys like you on this forum come and go many times, who believe that their engine is magic and they should make 1000 hp with 10 CR because they read something on a forum somewhere.
I call them CR deniers. Welcome to the club.

Take it easy prj, I understand what you mean, thank you for your help with that.
Even though there are 9.0:1 pistons the head was skimmed two times and that may be the cause.
Can you recommend the proper head spacer to fit in

Start by measure your current head gasked.
How thick is it when it was compressed?
Measure your combustion chamber volume with a spark plug in there and measure your piston volume in TDC.
Add the compressed head gasked to your math.
now you have your current CR.

Easiest way is to buy 2 of your last used head gaskets (because you know how thick they will be after everything is torqued down)
and just use 2 or disassemble them and mix until you have the correct CR.

No need to buy expensive laser cut pieces or something.

Best would be to change the pistons for proper 8.0:1 ones.

Alternatives:
https://www.bar-tek.com/de/1.8t-dicke-metall-zylinderkopfdichtung-bar-tek (https://www.bar-tek.com/de/1.8t-dicke-metall-zylinderkopfdichtung-bar-tek)
Of course they don't say how much it drops CR. Height is quoted as 1.92mm.

https://www.turbozentrum.de/Dicke-Zylinderkopfdichtung-VAG-18T-Metallkopfdichtung (https://www.turbozentrum.de/Dicke-Zylinderkopfdichtung-VAG-18T-Metallkopfdichtung)
They say 0.5-1.0 and the price is very good. Height is quoted as 2.35mm.

https://www.034motorsport.com/head-gasket-compression-dropping-multi-layer-steel-20v-1-8t.html (https://www.034motorsport.com/head-gasket-compression-dropping-multi-layer-steel-20v-1-8t.html)
Drops 0.5. Height not quoted.

Here's a website that uses a plate and they let you customize it:
https://www.turbo-concepts.de/motorenbau/audi-vw-seat-skoda/1.8t/rumpfmotor/verdichtungsreduzierung/149/verdichtungsreduzierplatte/spezial-kopfdichtung-1.8t-20v (https://www.turbo-concepts.de/motorenbau/audi-vw-seat-skoda/1.8t/rumpfmotor/verdichtungsreduzierung/149/verdichtungsreduzierplatte/spezial-kopfdichtung-1.8t-20v)
And here is another one, that is cheaper:
https://www.lspeed-racing.de/product_info.php?info=p1603_audi-1-8t-20v-zylinderkopfdichtung-mit-verdichtungsreduzierung.html (https://www.lspeed-racing.de/product_info.php?info=p1603_audi-1-8t-20v-zylinderkopfdichtung-mit-verdichtungsreduzierung.html)

I would just get the thickest one. The only thing the compression ratio is beneficial for on a turbocharged car on pump fuel is fuel economy, at least as long as it is higher than 7 or so.
So maybe you will lose 0.1L/100km, but you will easily and safer make more power. Which is the point I think?!

If your CR is now closer to 9.5 then the thickest variant will drop it around 8-8.2. I recommend using ARP studs with the proper torque too...
Alternative is the Turbozentrum multilayer, but the effect will not be that big. You probably need around 0.1-0.3mm extra thickness just to get back to your original CR. It depends how badly your head was warped when it was skimmed. And the Turbozentrum one gives you about 0.8mm over stock.

Keep in mind that whole timing map will need re-tuning on dyno, not just WOT. If you do not take advantage of the CR then the car will be slower off boost.

Also the 9.0:1 CR is ok for a standard K04, not for a turbo that can give 1.5x the output. The 9.0:1 is already a tradeoff between fuel efficiency and performance/reliability from factory.
You should be aiming below 8.5.
VAG dropped the CR by 0.5 going from 180hp to 225hp, which is only a 25% power increase.

What is the common practice with the timing at low end range with ~8.5 CR ?

iirc ~25-30 btdc at the underboost levels was the best for driveability but impact on the boost buildup is noticeable
stock ~10 deg building boost faster but lacks of response

btw id say 9.0 with k04 is the pretty good choice with proper fueling for a daily use, but at the limit of CR

He has TTE 480, not a K04...

Timing you have to find on dyno, my experience is that torque is always better when you get on the throttle, because with 9.0:1 CR knock limited absolutely everywhere at WOT, even if turbo is not spooled.

You can do tricks with spool, like using lambda 1 for quicker spooling as it creates higher EGT and so on.