Just for my bored information, I was just over on the APR website looking perhaps at a mild map towards the end of the year, and noticed something interesting.
For a MK7 GTI it gives a stock BHP Figure from the factory (in my case 230HP) and an APR dyno'd stock figure or 235HP (using 98 ron fuel). So a 5hp increase over factory (possible just due to 95 ron vs 98 ron)
However they also have the figures for the models with the new OPF/GPF which it states that their stock run only yielded 224hp.
Does the new GPF really account for an 11hp (5%) reduction in HP ? I'm pretty sure my May 2018 230PS GTI doesn't have a GPF so I don't think it affects me, but pretty astounded if that's true that it causes that much or a difference ?
That GPF really chokes up the car. Comparing my 2018 Polo GTI+ with no GPF to the wife's 2019 model with GPF (but otherwise identical):-
No GPF versions typically running 370Nm and 208ps (officially 320Nm and 200ps).
GPF versions typically running 340Nm and 210ps. So marginally more power but noticeably less torque.
I can say this is something very noticeable when I go from my car to hers - mine is much more eager mid-range than hers. Mine is 5% better on fuel economy too. Hers does seem a little more eager at very low throttle inputs, but mid to high, mine is more eager.
For the before and after remap dynos I've seen for the Polo GTI, The power and torque curves are significantly different between the GPF and non-GPF versions.
Someone did a GPF and non-GPF drag race and rolling race - both drag and rolling saw the non-GPF romp away early doors but the GPF one clawing back some of that deficit later. You have to wring the neck of the GPF'd one to get the most out of it because it develops its power later in the rev range, with less torque.
For your first point, taking a stock figure of 230ps and comparing it with a dyno reading of 235ps that just so happens to be running RON98 doesn't demonstrate that using RON98 on a car optimised for RON95 gave it 5ps extra. I'm surprised it was only making 5ps over stock (2.2%) if it can be considered 100% accurate - most performance VWs over perform stock by 4 or 5% from the before remap dynos you see kicking about, but how accurate is a particular dyno? You can only really compare the difference a remap makes (before and after dynos) - take 1 car and run it on 3 different dynos and you might get 3 different readings.
The car underperforming might've had a particularly crap run in, so many variables to consider. Who knows?
