997.1 Carrera S 3.8 to 4.1L rebuild - from windowed case to 406.6 HP
Here’s a 997.1 Carrera S engine project we recently wrapped up at Slakker.
This one started as a 3.8L M97.01 that came in after a track day failure. When this engine arrived, we knew something had gone wrong, but we did not know how bad it was going to be.
From the outside, we could see the case had damage and inside was no different.
Windowed case, spun bearings, carrier damage, and the oil pan had plenty of metal in it. Definitely one of the gnarliest disassembles we have seen in a while.
From here, we save what could be saved, replace what could not be reused, and built it back better.
The engine was rebuilt as a 4.1L setup. Some of the parts and upgrades included:
- Pauter rods
- Hartech racing sump
- 82mm plenum
- UAOS setup
- 8k valve spring package
- Replacement case/components where needed
- Full case work, sleeve prep, assembly, and dyno testing
The owner wanted something that would feel great on the street, handle a few track days, and still chase that 400 HP mark.
From the engine assembly, off it went to the dyno.
The cool part was that the owner flew in from Houston to be here for the dyno session. He got to see and hear the engine come to life in person, watch the tuning process, and be there when the final number came in.
Final result:
406.6 HP / 347.6 TQ
After everything this engine went through, seeing it come back together and hit the goal was a pretty satisfying way to close the loop.
From track day failure, to teardown carnage, to case work, to 4.1L rebuild, to dyno day, this one is now boxed up and heading back home to Houston.
Houston, we did not have a problem.
