Mark P

this post (and the graphs) are entirely about pump gas runs

Funkweasel

Maybe. I'd just do the O2 temp blocks. You'll see they're probably 850 or so.

Mark P

yeah, I'll check to see what ECUx has that corresponds to that

Funkweasel

increased timing, decreased iats, etc you still hit 5500rpm and it runs smack into a limit. We(AvantS4, Caltech, Moss) have been suggesting for a while that there is a restriction for power production. And since that occurs identically in race gas or pump gas, and now water injected it strongly suggests that it isn't exactly an "air flow" thing. It leads me to believe that the turbine inlet pressure is getting very high(ie restrictive turbine(and perhaps wastegate) and significant charge contamination is occuring. So the detonation resistance is very small(proportionally speaking for a given working octane value).

The results aren't exactly what I expected, but those are the best kind! I bet you could run quite a bit more timing though. 3degrees isn't very much. What are your FATS runs like for w/i versus non? Also you might consider just running water since you remove the variable of richening the mixture that way.

Mark P

And I have since added water instead of washer fluid. I may get a siphon and try switching fluids at Drag Day to analyze results - we'll see.

Funkweasel

a certain rpm then it tanks. Its pretty abrupt and looks like an airflow limit is reached. *However* since it seems to occur at different (higher as octane goes up generally speaking) rpms its certainly not a specific airflow limit right? ie if you couldn't move more air the rpm at which this occured wouldn't move. Yes you'd produce more power on race gas, ie timing/leaner/etc, but the actual rpm that it occured at would be the same. But since it moves up(it does right, I think I need to download your spreadsheet to check) I'm thinking it could be reversion doing it. If however its 5500rpm where the table to linear drop occurs everytime its a clear airflow limitation. Probably the turbine in either case is the problem.

Funkweasel

So Ari's K04 car->Note the 5500rpm point on the torque plot.
<img src="http://pictureposter.audiworld.com/15175/ari_race_dirtymxxxr.jpg">

The ITS big turbo car-&gt;Note the ~5900rpm point on the torque plot. These are the rs6 wheel turbos, unknown turbine side mods.
<img src="http://pictureposter.audiworld.com/15175/ktr_its_rsk04.jpg">

AND ohiok04s4's plots using iirc rs6 wheel turbos-&gt; Note that point is the same for race AND pump fuel.
<img src="http://pictureposter.audiworld.com/36999/race_vs_pump.jpg">


Very interesting no? Looks like it actually could be somewhat related to the compressor side?