Turbos: to boost or not to boost...that is the question.

[MarkB]

Email me the spreadsheet and I'll see what I can do...

[S4TAN]

YGM...

[SimonS4MTM]

Here are mine.

1920 1210 1220
2000 1250 1270
2080 2160 1310
2200 1980 1400
2280 1980 1540
2400 1960 1720
2520 1960 1860
2680 1980 1980
2880 2000 2090
3000 2020 2080
3160 2030 2030
3320 2030 2010
3480 2040 2040
3640 2100 2070
3800 2100 2060
3920 2090 2050
4120 2060 2080
4280 2030 2070
4440 1990 2040
4600 1960 1980
4760 1930 1950
4920 1900 1920
5040 1880 1880
5200 1880 1850
5360 1880 1840
5480 1880 1840
5640 1880 1850
5760 1880 1850
5880 1850 1820
6000 1820 1820
6120 1800 1780
6200 1790 1770
6320 1780 1770
6440 1760 1750
6560 1760 1730
6640 1770 1740
6640 1010 1750

[SimonS4MTM]

and graph

[S4TAN]

That looks good Simon - your car seems to spec. peak boost at ~2Krpm but you don't get actual peak boost until ~3Krpm - do you notice any turbo-lag when driving? Also, was this a 3rd gear FATS run? If so what was the time?

Judging from this the MTM map is similar to the DNA map and requests boost a lot earlier in the rev range than the MRC map...

[SimonS4MTM]

I think it was my FATS run. The time was 5.1 sec i think.

Do you think that the time it takes to reach spec boost is a problem, should it build faster?

[S4TAN]

Do you think that the time it takes to reach spec boost is a problem, should it build faster?

TBH I don't know - maybe that's the way the MTM map on the ECU works in conjunction with the N75 - i.e. doesn't let the boost build in-line with the specified level, but rather vents it via the wastegate until later in the rev range...........but i could be talking total arse; needs an expert to chime in here.......

[SimonS4MTM]

Experts, where are you.

Be good to see another graph with spec and actual.

[oliew]

2120 990 990
2080 990 990
2080 1250 980
2200 1670 1070
2280 2260 1180
2440 2260 1330
2600 2260 1490
2760 2260 1620
3000 2250 1820
3200 2240 1980
3400 2230 2070
3640 2220 2130
3880 2200 2160
4120 2160 2180
4400 2100 2120
4640 2060 2060
4880 2020 2010
5080 1990 1950
5280 1990 1910
5480 1980 1870
5640 1970 1850
5840 1950 1820

here is a graph of mine ive tried to find you a log from low down revs to see boost building looks like a WOT from 2080 (not sure what gear)but would be a flat road. requests decent boost very low down, it actually meets the boost properly at 3800, looks like a hot day as it was requesting quite alot. normally i dont see more than 1.2bar.
ignore the boost fall off, it actually works in my favour and allows more timing top end so i get nice fats times still.
Oli

[SimonS4MTM]

Cool, thanks

[S4TAN]

Here's a couple of graphs of my spec and actual boost plotted against rpm - my actual boost stays quite in-line with the specified boost (no hysteresis or lag) but seems to come in later in the rev range than the DNA and MTM maps...

[SimonS4MTM]

Your car seems to run backwards as well!

[S4TAN]

Well it's got a reverse gear so i should certainly hope so! Seriously though - i know what you mean; the first graph looks a bit odd - may have been the way i was using the throttle: it was a busy road that i was trying to do the FATS runs on and i kept trying to drop back from the cars in front to give myself a decent run....but caught up with them pretty damn quick (sometimes too quick to get to 6500rpm - i think that first graph is a case of that and therefore misrepresentational - just ignore it and look at the 2nd graph)!

[SimonS4MTM]

Its just that the first graph appears to have the rpm running from right to left, not left to right

[S4TAN]

It may have been the flux-capacitor kicking in too early and sending me backwards in time...