Fuel Trims during WOT

[xbrandino]

It has been a minute, but I have a log for you if you don't mind checking over it and seeing if there is anything that alarms you or any suggestions.

I have the rev limit set at 6200rpm.

The modifications on the vehicle are as follows:
- Stock Engine, Turbo and Intercooler
- E30 Mix (EU98 + E85)
- Autotech HPFP
- Full custom metal intake
- VTCS Delete + Ported intake manifold

[xbrandino]

The log didn't send, I uploaded it to Google Drive instead.

https://docs.google.com/spreadsheets/d/ ... ue&sd=true

[mituc]

Don't worry about the STFTs at WOT, that's how they look like.
You could definitely give it more timing, the timing values look like for stock fuelling and with such a high ethanol mix there is no way you can benefit from using ethanol other than timing.
Also, increasing the rev limit to 6500rpm or back to factory 6700 should not be a problem, the cooling effect and knock protection you get from the ethanol will make things a lot easier on the engine than when using pump gas (even though at these levels the engine is not stressed at all).

[xbrandino]

Okay, I can give that a try.

How much more ignition are we talking? When I was initially tuning and plotting the data onto Virtual Dyno it claimed I was loosing / not gaining any more power with the ignition changes, or maybe it was wrong.

In terms of load, what do you think I can target and reach throughout the rev range, ideally 3500 - 6500 and maybe below 3500 should I reduce the load to save my rods? It seems as my wastegates still have more headroom.

Another issue I found is I would have an overboost problem every single time I did a pull, if I went flat at 2800rpm it'd spike to 2.4 load at 3200ish and then come down to 2.2-2.3. How can I avoid that from happening, it looked like the car was increasing wastegates for whatever reason which caused the unexpected overboost. Are my load targets too high in that area that it is increasing wastegates by 20%?

Besides all that, I will say the car does drive very solid compared to before.

[mituc]

For ignition you can try small increments, like 0.5 degrees at a time in the relevant areas.

I would not go above load 2.3 (pump gas) on these engines before 3500rpm. At 3500rpm upwards it's fine. Remember that the actual enemy of the rods is the sudden increase in torque, so along with load (which is air flow at a given RPM point) you also have to take into consideration the itnigion timing to get a good point of reference. Load 2.3 at 3500rpm with 3 degrees of timing is less than load 2.25 with 6 degrees of timing.

For the overboost issue... post a log.

[xbrandino]

Interesting about the load, you mean I can increase up to 2.4-2.5 or more as long as torque doesn’t have any unnecessary jumps.

[mituc]

Since you had to scale your MAF curve up for the ethanol content then maybe, yes, but remember timing is also an important factor in all this. Load alone will not tell you the whole story about the cylinder pressure (so torque).
Also, without making any changes to the tune you took the previous log with, do a 4th gear pull to see if all the calibrations still work properly when there's mechanical and thermal stress applied for longer.