prj tuning

He who stops being better stops being good.

It has been a while since the last update, mostly due to an extremely busy schedule.

The partners list has been significantly expanded.
Particularily, I now have distributors/partners in Russia, East coast US,  Romania and an additional one in Poland.

Additionally the development of the Audi inline five cylinder ECU is now complete.
Some highlights, of the custom developments I and my partners can offer on this ECU:

  • MAFless (speed density) load computation
  • HFM5 big MAF conversions
  • Launch control with antilag
  • Flat shift
  • High-speed simultaneous datalogging of over 30 channels in the ECU, including per-cylinder knock logging

All of this logic is implemented inside the ECU firmware. No need for any boxes or converters!


JNL Racing Audi S6


  • 2.5L stroker engine built by JNL Racing, 8000 RPM rev limit.
  • JNL Racing cylinder head
  • 7A exhaust camshafts on inlet and outlet
  • JNL Racing intake manifold
  • Tubular exhaust manifold
  • HTA3582R with 0.82 A/R hotside
  • Tial wastegate
  • Aftermarket boost control solenoid with AN fittings
  • FMIC
  • Dual Bosch 044 fuel pumps
  • 850cc ASNU injectors with EV14 cores
  • 4 bar Fuel pressure
  • Custom fuel rail
Engine management:
  • Motronic 2.3.2 – fuel, timing, knock and boost
  • Speed density conversion, MAFless
  • Fuel pump control – second fuel pump brought online based on required fuel flow (custom software on stock ECU).
  • Launch control


  • 650 hp and 770 nm on Dyno Dynamics
  • 2.6 bar charge pressure
  • 2 bar @ 4200 rpm in 3rd gear, 2.6 bar @ 4400 rpm.
  • 2.3 sec FATS on a 2 ton car

It is now possible to map the 2.2T Motronic to run off of the MAP sensor instead of the MAF.
The speed-density calculation is fully implemented in custom code in the ECU.

The upsides and downsides of running speed-density are:
+ No need for a MAF, so plumbing is simpler.
+ Atmospheric dump valves and an atmospherically vented N75 can be used further simplifying plumbing.
+ No problems with the MAF maxing out, as MAP sensors are readily available even for 6 bar boost.
+ Little effect of air leaks on cylinder charge calculation.

-  The MAP signal is somewhat slower than the MAF signal.
The air charge calculation relies on an engine efficiency map in the ECU, thus if engine efficiency (flow) changes, it means that the air charge calculation will be wrong and a remap will be required. For example changing the intake or exhaust manifold, camshafts, porting the head and so on.
Difficult to dial in the VE table properly on the road, as every possible pressure and RPM has to be visited, because linearization is RPM and MAP based.

Compared to mass-flow:
+ Directly measures airflow, so changes to engine efficiency do not affect charge air calculation.
+ Somewhat faster signal than a MAP sensor.
+ Very easy to map on the road, as a pull goes through the entire range and linearization is flow based.

All air flow must be re-circulated, no air can leak after it has gone through the MAF, as otherwise the charge calculation will be off, more difficult to plumb
If the MAF maxes out, charge air calculation does too. Meaning that after it does the ECU essentially runs Alpha/N, which is inaccurate.


Hannes’ Audi TT


  • 9.0 CR pistons, overbore to 1.9L
  • Precision 5857BB, 0.63 A/R
  • Forge 007 dump valve
  • 875cc/min Siemens Deka injectors
  • Bosch 044 in-line fuel pump
  • Light flywheel + clutch
  • Stock head, stock cams
  • 2.0 TFSI coilpack conversion


  • ~430 HP and 530 NM – retune after head is upgraded and CR dropped.


Site back to normal

The site is pretty much back to normal, a few pictures with some dyno graphs were lost, but other than that everything should be functional again :)


Lost data

Hostgator managed to lose pretty much all of my data, that I’ve had on my account, accumulated since close to 10 years.

I am slowly restoring everything, but it will take me some time.

I quote:


This is a courtesy notification to let you know that the array of hard disks for /home on gator31 experienced a catastrophic failure earlier today. We are currently attempting to recover what data we can from the disk array. However, a successful recovery of any data is looking increasingly unlikely.

We have opted to restore accounts from our own backup system onto a new gator31 to restore service to as many customers as quickly as we can. However, our backup system does not contain a copy of your account due to the large amount of disk space that your account used. From section 7c of our TOS:

Any shared account using more than 20 gigs of disk space will be removed from our off site weekly backup with the exception of Databases continuing to be backed up.

If you have a current backup of your data, please let us know & upload it to your account as soon as you are able. We will restore that backup to restore service to your sites.

Let us know how you would like to proceed.

Best regards,

Brian L.
Linux Systems Administrator


Angus’ ur-Quattro


  • AAN engine
  • 01E gearbox
  • GTX2867 turbo
  • 630cc Siemens Deka injectors
  • 044 fuel pump
  • JNL Racing ported head
  • 2x SMIC
  • 3″ exhaust system


  • 2.7 sec FATS
  • 2.5 sec 60-90 mph
  • 1.9 sec 60-80 mph



Sergei’s RS4

After countless experiments with my own RS4, it was time to make the next step, and start tuning decently powered ME7 cars.


  • K04 hybrids
  • 2.75″ DP’s
  • MTM exhaust
  • Lightweight flywheel
  • 710N dump valves
  • 044 fuel pump with relay
  • 980cc Bosch Motorsport injectors


  • 2.8 sec FATS
  • Sub 10 sec 100-200 times

LPG – liquid petroleum gas.

Most of us have probably heard about it, let’s see how production cars are converted to it, and what is usually done wrong.

I will talk about the 4th generation LPG system, where extra holes are made in the intake manifold and an injector is added for each cylinder.
Technically the system is pretty simple…

How it works

From a mechanical standpoint we have a high pressure tank, from which the liquid gas goes through an evaporator, that takes it to it’s vaporous form. From the evaporator it is distributed to the injectors via a common rail.
After the injectors are nozzles, which are sized to a certain size, according to calculations. So the same injectors can be used for many different applications and the injected quantity is adjusted by sizing the nozzles.
The evaporator also serves as a pressure regulator for the fuel, and is usually connected to a vacuum line in the inlet manifold.

Electronically most LPG ECU‘s are fairly simple. The cars petrol injectors are re-wired through the LPG unit, and the LPG unit just gets the reading from the main ECU in regards to the injector pulse. After it gets the start of the injector pulse it can correct it to be longer or shorter. It can also switch the gasoline injectors on or off.
The LPG ECU tends to have a gas pressure and temperature sensor and also allows for correction based on LPG temperature, as the density of a vapor fuel is affected quite a bit by temperature.

The way these systems are normally installed, is that they are set up to turn on only after a certain engine temperature is reached (the car only starts on petrol), and then it is calibrated with a narrowband sensor so, that the mixture is roughly stoichiometric in the cruise area. The ignition timing is not touched in most installs, and the car feels down on power. The nozzles are also rarely big enough for the car to work correctly in the entire range.

How it should be done in an ideal world

The best way is to use the additional LPG ECU to only provide correction for fuel temperature and switching settings. The engine management should be done by the already existing ECU by facilitating “map switching” based on whether LPG is used or not. This means that a signal should be taken and fed into the ECU.

A real world example

The car I will talk about is an old Audi V8, with the PT 3.6 liter engine, 2nd generation Motronic management with dual distributors and a 4th generation “Tornado” LPG system.

Read the rest of this entry »


  • Std. ADU engine
  • ADU gearbox
  • 4 bar FPR
  • RS2 fuel pump


  • 3.1 sec FATS