Ignition timing and compressor maps.

[spen]

Dummi, it is an extrapolation. I'm pulling 364 g/s by 5700 rpm. If I plot all my g/s readings vs rpm and watch the tailoff it should be around 380 g/s by 6800 rpm. 380 g/s is also in agreement with the very crude g/s / 0.8 = bhp = 475 bhp which is in agreement with Doug's guess of 470 bhp. ie it can't be a million miles away from the truth.

[S2tuner]

S4 RS4'd and Undefined Tuner Map

[spen]

S2tuner. Dunno about that. I guess kies4 didn't want to name drop??

*MUCH* more interesting from my perspective is any comment on my reasoning in the posts above. I know you need to keep a lot back as it's your living, but can you enhance my understanding? Have I got it right, nearly right, or way off the mark?

And, if I may ask, what turbos do you have on that '1998 LHD S4, RS4 engine, PSS9s, dual 2.75" exhaust with no cats, FMIC, 531BHP/515ft-lb, 19" BBS CH, B7 RS4 brakes'?

[s4woody]

K04's ported and polished hotside's i believe..but im probably gonna be proved wrong..

[S2tuner]

Standard K04s. My car being an experimental project, I'm running 2.0 Bar peak dropping to 1.6 at redline. Yes, that's 28-29psi dropping to 24.

[kies4]

Minhea just a dig in sympathy for the old devil.

[spen]

Minhea, what sort of timing do you achieve with 28 pounds of boost? How many miles / track days have the K04s provided whilst running totally off the top of the map?

[saf]

Mihnea, is there a danger of running 2.0 bar as it seems way over what the compressor map says the turbo can take? Or are your turbos just blowing hot air at that level of boost?

You seem to be running the same boost as straight RS6 turbos.

[S2tuner]

Mihnea, is there a danger of running 2.0 bar as it seems way over what the compressor map says the turbo can take? Or are your turbos just blowing hot air at that level of boost?

You seem to be running the same boost as straight RS6 turbos.

One fact is that my engine has the tubular exhaust manifolds, full exhaust and BIG intake pipes. The turbos seem to be taking 2.0 bar without too many problems, of course the compressor efficiency is out the door, but the engine runs really strong!!! On an engine with normal RS4 intake pipes and simply gutted precats and stock manifolds, I wouldn't even think about running 2.0 Bar, no way jose

My timing is around 9-12 degrees midrange and 24-ish top end if memory serves from the last time I logged the car (which is about 2 months ago). RS4 engine with stock compression ratio, it's just a temporary engine whilst the 3.0 is ready to drop in.

[s4woody]

Ported, polished and clearanced K04s with 0.7 Bar actuators
Custom tubular exhaust manifolds ceramic coated
Custom turbo intake pipes in 2.5" diameter, tapering to slide fit on the compressor inlets
Custom compression dropping Headgaskets from (8.2:1 CR)
2001.5 intake manifold (no mods)
APR Bi-pipe
N249 delete
RS4 MAF and Y-pipe
Custom dual 2.75" exhaust from turbos back, no cats and one silencer
Bosch motorsport 044 special 10 Bar fuel pump
728cc/min injectors at 4 Bar rail pressure
FMIC and custom IC piping
Custom MRC Remap
Custom aluminium flywheel and Sachs race sintered metal 4 puck clutch kit.
RS6 EGT Sensors
Result - 515bhp & 505lb/ft !

like he say's standard k04's...

[smurfbus]

history is a funny thing : )

[DavidT]

Woody, that is the S4 engine he had in his S4 before. Now replaced with an RS4 engine I think.

[spen]

Minhea, I like the sound of that combination of boost and timing!

Can you post the spec of the larger K04 intake plumbing you're talking about?

[DavidT]

Moved out to tuning & mods by me so everyone can enjoy it.

[S2tuner]

Ported, polished and clearanced K04s with 0.7 Bar actuators
Custom tubular exhaust manifolds ceramic coated
Custom turbo intake pipes in 2.5" diameter, tapering to slide fit on the compressor inlets
Custom compression dropping Headgaskets from (8.2:1 CR)
2001.5 intake manifold (no mods)
APR Bi-pipe
N249 delete
RS4 MAF and Y-pipe
Custom dual 2.75" exhaust from turbos back, no cats and one silencer
Bosch motorsport 044 special 10 Bar fuel pump
728cc/min injectors at 4 Bar rail pressure
FMIC and custom IC piping
Custom MRC Remap
Custom aluminium flywheel and Sachs race sintered metal 4 puck clutch kit.
RS6 EGT Sensors
Result - 515bhp & 505lb/ft !

like he say's standard k04's...

That engine is now sold and runs happily with H-profile rods and RS6 turbos in a french customer's car. Read my sig woody, it says RS4 engine in there, and my old ported and polished turbos are on another french customer's S4 engine