Simple way of looking at it.... how many cylinders does the rs4 have..... and the engine size..... then calculate the rough max flow you need for the bhp that engine produces..... you'll find that the flow rate is much lower than what would be required for that of a 2.0 4 cylinder turbo.

Additionally I believe conclusion testing has been performed on the physical injectors proving the above mentioned.

Or do I have the wrong end of the stick?

From all of the real world results the RS4 injectors can simply flow more fuel. There are no test around that prove otherwise. People have done tests but did them wrong.

Once the injectors are tuned correctly like i now have them they work great. No black smoke, good burn and good results.

You lost it mate, you lost it.... You are 101% wrong
RS4s are quite bigger than S3

The point is WHY VAG decided to install that big injectors in a low power cylinder 55hp/cyl instead of 62hp/cyl S3 2.0TFSi

The answer is because they spray for a shorter time. If you know where to look in RS4 .bin then you can see injection starting and closing angles.


Now installing the RS4 in a 2.0TFSi isn't an easy job. For proper fixing you need to recalibrate more than 20maps and of course the injection angles.
Why smokes like a diesel?
Why is lean in lambda and my tail pipe smokes like hell?

All these WHYs are solved with the proper tune of the RS4s

I have spend over 1 week to make them work perfect and what I can say is that they are excellent injectors for the 2.0TFSi for turbo upgrade with no any issues if you know what to do.


Where starts the problem and when the tuners looses all the game with these injectors is because they have no idea what a Direct Injection system is and how it works. Also they don't know how the Direct Injectors react and how they lag.


I am tired saying all the time, buy the Blue Bosch book and read first and then work with MED9


Some extra info
RS4 and power output
480hp @ 130bar
520hp @ 140bar
560hp @ 150bar
600hp @ 160bar
630+hp @ 170bar

I am working with special fuel pump and special PRV at 175bar with RS4s and we got 625hp @ 2.5bar ct boost with an PTE 6262

Thanks for the information.  They do say that you learn something new every day

correct

The RS4 spray angle is designed for RS4 engine's pistons surface and the different injectors seat position
Of course this angle is wrong for the 2.0TFSi engine but with the forged flat pistons it works fine.

A little black smoke from the exhaust but almost undetectable, in WOT condition, is acceptable.
You can also avoid this but you will miss a lot of effective injection time which means less capable hp

After a lot of testing and weeks of R&D I decided that this is the best injection angle profile!

Great response and info once again from RaraK & hammersword. Thanks guys.

Once warm up injection angle is tweaked you get pretty good cold starts. Then the other injection angle tables  help reduce the black smoke to near nothing. Small amount on WOT.

I should mention i have flat top forged pistons. Previously with OEM pistons and RS4 injectors the car looked like a diesel truck from 1964.

I've got to say I am incredibly impressed with the knowledge on this forum. I just started attempting to tune using Eurodyne Maestro and I have not found so much good info as this thread has. I am also running rs4 injectors but I am far behind you guys, still researching what most of you say to get a full grasp.

Another issue with Eurodyne is that the maps are very limited. I had asked Eurodyne to add the injector angle map for my ECU to Maestro, but no such luck yet...Does anyone know if he is on here, or better yet does anyone here have significant pull with him?

Thanks guys

Martin