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MAF readings and HP estimates.

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OllieVRS:

--- Quote from: Pudding on August 11, 2023, 10:01:49 pm ---ROH ECT has a K04 conversion, but your 240ish hp is about right for a stage 1 K03 tune.

Your VE curves don't look wildly different to be fair, although if your MAF is peaking out at redline, it's making the power from revs rather than flow.  Any number of reasons for that, including turbo size differences. K04s pull harder up top as they're less restrictive than K03s.  ROH's VE curve is very typical. It should reduce approaching redline as the engine simply runs out of flow.  The cam profiles, valve sizing, head flow and throttle body can't get any more air in. Plus the turbo's turbine wheel and housing size become the mother of all exhaust restrictions at that point also.

4th is the right gear to do it in as it's 1:1, so takes gearing out of the equation. Shorter gears increase torque at the wheels, taller gears reduce it, but that only becomes a factor on the coast down fudging on a rolling road.  But on the highway, there's more load in 4th, so works the turbo harder and there's also enough legs to max it out without doing crazy speeds :happy2:

The MAF divide by 0.8 or times by 1.25 often comes under criticism as a rubbish metric, but it's actually not far off, since MAF and fuel injection timing are directly proportional to each other. Every time I've used that method for road tuning, it was only 5% off on a rolling road.

--- End quote ---

Great insight, thanks!

MAF points to max power at nearly 7000RPM, Torque spec points to max power at ~6200RPM.

Also the '238hp' I posted earlier definitely comes up under 'rubbish metric'. I dynod at 232hp on a proper dyno, running enough octane booster to make my 95 octane equivalent to 99. But you're right, less than 5% off.

I hope to get my tune updated on the dyno in a couple weeks, but only on 95 as it would be dangerous to map for 99 in a country that doesn't sell anything it. My HP on 95 is 220-225, so hoping for 235 at least. Irish 95 is pretty depressing after all though, so can't have my hopes too high up. Allegedly Irish 95 is actually worse for mapping than Great British 95, according to online rumours.



EDIT: Forgot to include, finally learnt how to use Excel, here's a couple neat graphs from logging on just 95:





And some timing pull, to do with the lower octane or is does higher octane get this too? Haven't had a chance to retest with booster yet.

pudding:
Oh dear, maybe move to England  :grin:

Yeah I was just looking at the timing pull and anything over 6 isn't great to be honest, but not critical. Even standard ones usually pull -4 to -5, they run pretty close to detonation from the factory.  -7.5 certainly isn't disastrous, so don't worry about that too much. If you see figures of -10+, you need better fuel or a remap of those load areas.

From memory, those aren't the actual degrees of ignition retard. It's a weird Bosch way of doing things. It retards in steps of 0.75 degrees, so it would 7.5 x 0.75 = 5.6 actual degrees of retard, which at 1700rpm isn't anything to lose hair over.

The stock TFSI timing map is pretty gnarly. At some load points there is 0 degrees advance, sometimes minus degrees. They're just all over the place, but it all works hand in hand with the VVT and other parameters, but anyway, I've not seen anything in any of your charts that rings alarm bells  :happy2:  You have very low timing pull from 3600 upwards, which is the danger zone.  At those rpms, excessive detonation is game over as you don't have time to back off, and you can't hear it happening.  I think the ECU's retard limit is -25KW (18 degrees), so you're well within the limit.

Obviously you want as close to zero pull as possible for power consistency and engine life span, but even with 99 RON in England I was seeing -6 on my ED30 with Stage 1.

Also bear in mind, a heat soaked intercooler will raise intake temps, which will also cause the timing pull.  45 degrees C intake temp is when the ECU starts pulling it.

OllieVRS:
Finally, got mapped. Unfortunately no dyno as the dyno my tuner normally borrows was too busy, so just a road map for now. He says we'll get the map fine tuned when the dyno is free, but who knows when that is :grin:

Also, I've figured out that the HP conversion formula I was using was for BHP, not 'PS', or the version of HP I like. God damn you imperialists, making me think I have 3 less HP. So all numbers presented below (and previously) are all in imperial horsepower, not metric.  :doh:

Anyway. The numbers. There's some weird anomalies like high HP near redline so I've included timing pull again and intake air temp.


95 Octane



Horsepower ≈ 250BHP*


95 Octane + NF Sport Octane Booster



Horsepower ≈ 259BHP*


*To be taken with a grain of salt, as this is just VCDS logging and anomalies occur in the data. Only a dyno will reveal a more accurate number. I also just threw in the octane booster right before the second run without filling up, so may not have been mixed perfectly.


I'd like to know what you think of the timing pull, @Pudding . Tuner said he changed the timing slightly to squeeze out more power. She's hitting as much as -9KW timing pull on 95 in the peak power RPM range.

Cheers!

pudding:
-9 is a tad high but not excessive. Personally I wouldn't want to see any more than -6, but the octane booster appears to reduce it  :happy2:

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