It makes no sense to try to wring high performance out of a naturally aspirated 2.5 4 cylinder. It would be cheaper to sell your naturally aspirated car and buy one that comes with a turbo or the 6 cylinder.

Talk to Delicious Tuning about it if you wish. To make serious horsepower out of a naturally aspirated 2.5 you'd need to make it rev to 8000 RPM to get enough air/fuel pumping though it. All of the porting and polishing and tuning in the world can't make a low-rpm low-displacement naturally aspirated engine powerful.

 

Talked with my shop guy about it. What he had to say was.. Price too low, engine probably been beat to death and will probably never run right because it has a tune. Have to take it to a dyno and pay to make sure it's running right, etc.

He suggested JDM.

 

Not going to gain almost anything without turbo or a big compression change.

 

Even with big changes (and I’m talking BIG changes; $5k+ worth of work), the NA EJ engines are really lackluster power producers. I can’t find it now, but I read an article recently with a guy pushing a naturally aspirated EJ25 as far as he could, and he managed a little over 250hp. That was with completely custom cams, I believe he had forged pistons, he did something to the compression and fuel injectors, the list goes on.

As much as we all love these weird little engines, they just suck at making power without boost. You’d get far more bang for your buck by putting a turbo in, or going for an NA EZ30. Those two extra cylinders are the only realistic way to get good results for this kind of build.

 

Now if only an EZ30D was a drop-in on an EJ251.

Seriously eyeing up a low miles EJ201 JDM.

Thought occured to me, "just get an EJ22" people have made it work.. how hard is that?

Also. Does an EJ20 even HAVE a Head Gaskets issue?

Has been suggested the EJ25 is "too big" and "sucks" but an EJ20 or EJ22 is "bulletproof".. so I have some options but yeah what should I do ?

 

 

Given the choice.. Would you all choose the JDM EJ20 (?)
.. or this engine ??

ej251 engine With Built Heads, Refresh, Tuned Ecu | eBay

<p>140k mile shortblock pulled from 01 Legacy GT</p><p>ported/polished SOHC heads</p><p>Delta 2000 cams</p><p>Supertech springs/retainers</p><p>Intake manifold painted red</p><p>Head gaskets, valve cover gaskets, and timing belt+water pump have 5k miles on them </p><br><p>Will come with...

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