Good evening,
I own a S4 B5 2.7 Biturbo.
After rebuilding it I have Problems with high EGT and after endless discussions I will try to ask in that forum because I think there are some experts around.
Long Story short: The Engine got rebuilt with new Pistons, rods and N/A Heads. New Valves etc.
Setup:
- complete RS4 Intake
- Hybrid Turbos (750) with K06 Exhaust Housing and 55mm inlet
- 3 inch DP
- Bosch 980 Injectors
- E3L Fuel Pump
- Big Exhaust Manifolds
Car runs great!
But if I go WOT the EGT rises extremly fast. At the end of 4th gear I hit easily 1000°C (1800°F) And thats not what i wanted
1. Its not Software related. I got my file checked 3 times and all of them said its fine.
2. There is enough Fuel. I checked with wideband O2 Sensor and everything operates as it should (afr 11,5 - 12,0)
3. I almost hit the MAF limit. So its somewhere around 600hp. Boost is 29 PSI tapering to 21PSI. Should be easy for the turbos.
4. I cant get "good" timing. Even on almost stock Ignition Map it pulls timing. (with 102 Octane Fuel!)
I think that 4) is my problem. On my other Setup before i could easily go with 20 degree BTDC under load. Now I can hardly get 15.
I also noticed, that my boot got sprinkled with black soot (little points all over the Trunklid).
I will pull the engine again to reduce the Compression Ratio. (at the moment 8.5)
Maybe someone has another Idea to look for.
Thanks in advance!