All Things Mk5 > Performance Modifications
Has my car been re-mapped?
coldcuppatea:
I've just changed my 2015 Focus ST for a 2008 GTI. As I expected, the Golf doesn't feel as punchy as the Focus and I was considering getting a remap. I thought I'd get an idea of pre-remap data by doing some logging from the OBD2 port this evening. I was surprised to see the boost apparently peaking briefly at up to 25psi and holding 18 to 20 psi. From what I had been reading, I was expecting it to hold around 15psi.
However, I assume that if it's had some sort of "stage 1" map, it should have around 230bhp / 230lbft, which I would expect to feel similar to the Focus, but it really doesn't.
Can anyone shed some light on the boost levels? Does OBD2 report accurate levels?
Thanks!
pudding:
Standard boost is 0.9 bar iirc, so likely mapped.
It may not be a brilliant map and the Golf is a lot older than the Focus, so it's probably not a fair comparison.
Dan_FR:
Do not forget that almost all OBD logging using the MAP sensor provides absolute pressure readings, so you need to subtract approximately 1 BAR of atmospheric pressure to get the true positive 'boost' reading.
Subtracting approximately 14.7PSI from your readings sounds exactly like standard to me, with about 10psi peak settling down to around 6psi by the redline
post the data here if unsure
coldcuppatea:
Thanks chaps. I'm pretty sure that the boost values that are being output are corrected for atmosphere. The logs also include inHg for absolute manifold pressure which, when converted to PSI, were reading 14.4 psi higher than the boost value at the same point in time.
Unfortunately the data logger only seems to write one line of data per second, so the finer points are lost. I've plotted out a run from stand still through 1st, 2nd and 3rd using the launch control. 2nd gear (points 6, 7 and 8 ) are fairly representative of what I was seeing in the instant read out (18.5psi, 19.7 and 17.3).
There is a big spike to 29psi showing, which I'm guessing isn't good.
Sent from my iPhone using Tapatalk
Madone:
--- Quote from: Dan_FR on April 07, 2016, 11:58:52 am ---Do not forget that almost all OBD logging using the MAP sensor provides absolute pressure readings, so you need to subtract approximately 1 BAR of atmospheric pressure to get the true positive 'boost' reading.
Subtracting approximately 14.7PSI from your readings sounds exactly like standard to me, with about 10psi peak settling down to around 6psi by the redline
post the data here if unsure
--- End quote ---
Spot on Dan, fell into the absolute reading myself many moons ago. That sounds like stock levels to me also
Navigation
[0] Message Index
[#] Next page
Go to full version