Hello,
I've got this golf mk4 with the alh engine that I've been trying to tune using vagedcsuite, flashing with mpps13.
Everything is stock, except an egr delete, a straight pipe and 0.216 nozzles, so stock 10mm pump and vnt15 turbo.
After searching and flashing countless times, i've finally settled on a good pump voltage map for my setup (.0216+10mm pump) that I've found somewhere on this forum, can't remember where(thanks :angel: ). I know that for a good tune with modified nozzles, it is necesarry to start with a strong, calibrated n146(pump voltage map), alongside with a good SOI map, removing limiters in the SOI limiter map to take into account my advanced soi. Those two go hand in hand, by my understanding. After testing, I had great results with the calibrated n146 and soi maps, so I started adding fuel at 85 and 100% throttle in the driver's wish map.Then came the smoke limiter map. I've raised the smoke limiter map axis for 1000 and 1150mg MAF readings after removing MAF limits, since stock MAF only goes up to 1000mg on the map axis.
Next was the Torque limiter map, which should be the lowest of the 3 fuel limiting maps ( Drivers Wish-Smoke Limiter-Torque limiter).
In the TL map I haven't adeed much fuel before 2000rpm, due to too much torque for the stock clutch, gearbox and axles, gradually increasing fueling, maxing out at 57mg from 3333rpm to 4000ish, then slowly backing down to 49 at 5000rmp, where fuel is instantly cut (VP rev limiter-ish). So far so good.
Next on my list was boost map. Running the little VNT15 with this level of fueling isn't ideal, i know, but I'm planning on upgrading in the near future. The stock ALH turbo can do about 18psi sustained(1.25bar), or 2.25bar in the Target Boost Map. Also, a very important thing to note: increasing fueling causes the turbo to speed up faster. Researching, I've found that trying to achieve a lot of boost at low rpm when the turbo can't supply, the PID tries to increase boost by closing the vanes inside the vnt mechanism, resulting in massive, maybe destructive, boost spikes for the small vnt15. Fixing that meant lowering fueling and boosting at low engine speeds. That seemed to work quite well, I still need to tweak the N75 map. Also, I removed boost up to 2000rpm and 20mg and opened vanes in the n75 map, together with advanced SOI, in order to achieve better mpgs (which worked quite well for me). I've done this because the engine can burn up to 25mg of fuel without boost.
Logging in vcds in group 11, I'm almost meeting actual vs requested, so I think I'm on the right path.
After that, I've changed the boost limit map to 2.32bar absolute (+50mbar above requested) and the SVBL (single value boost limiter) to 2.35 bar, to take advantage of the actual requested boost. I'm still working on smoothing out the boost limit map to account for high altitudes driving, knowing that vw didn't make a very good job when creating this map..
N75 map is modified after logging group 11 in vcds. Higher numbers in the map means vanes open more ( less boost ), lower numbers meaning more boost. The 100% values in the n75 map match the values in the boost request map, where I'm asking for no boost.
Everything else is driving, logging, modifying and repeat, to get req. boost to meet actual.
Altough the EGR is blocked off mechanicaly, I've also deleted it via the map.
Going in depth about my 1.5 stage tune, I understand that the 10mm pump with 0.216 nozzles can deliver 57-58mg of fuel, so I've removed the 51 IQ limit that the edc15 has, pumped it up to 57mg of fuel. Also removing the diagnostig limit of 51mg that vcds displays ( now showing 57mg in group 01). All my modified maps go up to 57mg on the fuel axis. Removing the 51 IQ limit in vagedcsuite was done this way:
There are 2 maps with 5000mg limit. I've chaned the 5000 value to 5700 in both maps.


There are a couple of 51 values in the hex file. To modify them, go to actions, view file in hex, click find, hex values, and search for 27 33. 33 in decimal is 51. Replace the 33 hex value into the value you want ( for me 39, being 57 in decimal). Keep clicking on search next until you've modified all of the 33 numbers into the value you want. I used winols demo to see what 57 in hex is, since I don't have a winols license... :(
For MAF to be able to use more than 1000mg of air, I've changed 2 maps. Both had 10000 max, changed them to 15000. Change the left side axis to 15000 aswell. This should let you use more than 1000mg of air in your smoke limiter map.


Also, I've added 'launch control' to my tune and dynamic idle for better warm up times ( that helped ). Adding launch control means going to actions, click on 'activate launch control' and tune that map. To make dynamic idle work, I had to modify the 2 Idle RPM maps, mine idles to 1200 rpm up to 17C, then settles to 1000 until 90C.
Now, for the real experience. Numbers and values matter, but more important is how the car feels and drives. And how much smoke you puke behind lol. Smoke is bad( usually meaning unburned fuel, high exhaust temps, which are bad for the turbo), so I've adjusted things in a way that I got almost no smoke at WOT from 1500rpm up to 5000. Given that the clutch is stock, the IC ( intercooler ) and piping is stock aswell, I'm amazed with how well the car puts the power down. No clutch slipping is happening, a very small haze at WOT, and the car pulls like a train until 5000, while getting an average fuel consumption of around 5l/100km in normal driving conditions (cruising at 120kmh at 2500rpm). It's really something, this old tractor.. :lol:
Couldn't have been more satisfied with the result. Now, yes, I'm sure there are mistakes, and that the pros can pinpoint (that's the whole reason for this post) them, but overall, I'm very happy with the outcome.
As previously mentioned, I'm planning to get a bigger turbo, probably a 17/22, rebuilding my 10mm pump and upgrade it to a 11mm one, IC, upgraded clutch and even rebuilding the engine in the near future, but hey. I'm only a begginer.
Any advice is well received, aswell as eager critisim. What y'all think? :silent:

Here is the original file:


And the stage 1.5 :D :

why this changes??

the changes in N75 look like he wants to gain some efficiency in low load conditions

Indeed, the changes to the n75 map in that area were to increase efficiency in low load conditions. I've disabled the turbo request map in those areas, so I've disabled the turbo via the n75 map also ( 100% means vanes are open, so no boost is created, at least that is what I've come to understand after a bit of reading ). Doing this creates a lil bit more lag when I floor it from ~1500rmp, but after ~2000rmp the turbo spools up and it keeps pulling til 5000. Acceleration feels very responsive nontheless and it feels like I have to press the pedal less at same engine loads/rpms.
As for the other 3 maps, I didn't modify them at all, in my file they have the same values as stock, haven't touched them.

ph33r wrote:the changes in N75 look like he wants to gain some efficiency in low load conditions

how he gonna gain efficiency if the values are for all open N75

xaparrix wrote:

ph33r wrote:the changes in N75 look like he wants to gain some efficiency in low load conditions

how he gonna gain efficiency if the values are for all open N75

They aren't open for all of the values, only up to 20mg of fuel, and in low load conditions up to ~2000rmp, as I've stated earlier. I've done this because, in theory, the engine should be able to burn 20mg of fuel cleanly, without additional boost. Exhaust gases spin the spinny boy to make boost, which creates drag on the engine, so by telling the turbo to not make boost in those low conditions, together with earlier SOI, should make it more efficient in those low rmp and low load scenarios. I know this is what worked for me and my little wagon. But it's a fact that my car easily beats an Audi A4 sedan with the 1.9 131hp engine (asz) in a straight line.

Since then I've made some modifications to my maps, including another pump voltage map, will upload and discuss them soon, but I'm rebuilding the turbo rn. It hasn't failed (yet), but I've decided to take it out because it started making a weird pooooof sound when lifting my foot off of the accelerator pedal. And sure enough, there was a lot of back and forth play in the turbo shaft, and the compressor wheel had some damage to it aswell. It was a second hand unit ( I can tell because there are paint markings on it which indicates that ), so I'm glad I took it out to refresh it. I got the car just a few months ago, and there are still things to do on it.

Gvr wrote:

xaparrix wrote:

ph33r wrote:the changes in N75 look like he wants to gain some efficiency in low load conditions

how he gonna gain efficiency if the values are for all open N75

They aren't open for all of the values, only up to 20mg of fuel, and in low load conditions up to ~2000rmp, as I've stated earlier. I've done this because, in theory, the engine should be able to burn 20mg of fuel cleanly, without additional boost. Exhaust gases spin the spinny boy to make boost, which creates drag on the engine, so by telling the turbo to not make boost in those low conditions, together with earlier SOI, should make it more efficient in those low rmp and low load scenarios. I know this is what worked for me and my little wagon. But it's a fact that my car easily beats an Audi A4 sedan with the 1.9 131hp engine (asz) in a straight line.

Since then I've made some modifications to my maps, including another pump voltage map, will upload and discuss them soon, but I'm rebuilding the turbo rn. It hasn't failed (yet), but I've decided to take it out because it started making a weird pooooof sound when lifting my foot off of the accelerator pedal. And sure enough, there was a lot of back and forth play in the turbo shaft, and the compressor wheel had some damage to it aswell. It was a second hand unit ( I can tell because there are paint markings on it which indicates that ), so I'm glad I took it out to refresh it. I got the car just a few months ago, and there are still things to do on it.

even a PD150 is beated by an VP110 whit a good tune..

True that :D
Today I cleaned the vnt mechanism inside the turbo, still waiting for the core and actuator to arrive, can't wait to test it.