A stock Ej205 engine can handle up to about 8-9 psi of boost before fuel delivery becomes an issue. Beyond that, you're looking at around 12-13 psi with upgraded injectors. 18 psi is achievable, but after that you start running into problems with the ringlands.
Frequently Asked Questions
How much boost can a EJ20 handle?
300 whp: The EJ20/EJ25 engines can handle 300 whp maximum with stock internals with no further modifications other than a proper fuel management tune. 400 whp: We suggest a set of forged AMR pistons and billet rods to safely boost up the engine.
How much HP can a EJ20 block handle?
A safe maximum boost for the EJ20 engine is 400 horsepower.
How much boost can you run on stock internals?
Most people can safely run around 400-500rwhp on stock internals.
Is the EJ205 a good engine?
Yes, it is a reliable engine and will make around 250hp. However, there are few tuning options available on the stock ECU.
How much horsepower does an EJ20 make?
The EJ20 makes 150 horsepower.