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.
Sources
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