Subaru EJ20 Normally Aspirated
Unusually this customer was converting a Subaru EJ20 turbo engine (similar to the one pictured, © Subaru UK Ltd) to normally aspirated induction.
The compression ratio required was 11.0:1, with a bore size of 93.50. The sample piston supplied was a standard EJ20 low compression piston with a flat bowl and two valve relief slots. The finished piston has a raised intruder between the valve reliefs and has the correct volume to achieve a compression ratio of 11.0:1.
In addition to the sample piston, we needed the following information about the customer engine:
- Bore size
- Deck height /clearance
- Head gasket thickness
- Cylinder head chamber volume.
The SubaruEJ20 OE low compression piston and the finished forged high compression piston
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