parts to upgrade 2.5L to 3.0L

[quadrophiend]

Hey,

I was wondering if anyone knew what specific parts I would need to purchase to 'transform' my e46 325 to the rough equivalent of a 330?

I know the bore is the same, but stroke is diff.. also the cam is forged...

any and all help is appreciated... I am probably going to do this conversion soon, but would rather purchase individual parts since my basic engine is perfectly fine, than purchase a whole new engine...

TIA

-Tre

[Jared at Pelican Parts]

Are you looking to build your 325 motor for more power?

[quadrophiend]

Yes. I am looking to, essentially, turn it into a 3.0L. I know it will never have as much power as a stock 330 with just some 3.0L M54 parts, but I should be able to crank out enough horsies to be close - at least in theory, since only a few things differ between the 3.0L and 2.5L M54..

I just don't know what all internals I need to get..

[Jeron]

You're not going to be able to buy 3L parts, put them on your 2.5L and get 3L performance.

You could try adding aftermarket parts to bump the hp but that will be expensive and wont increase the value of your car. Why spend a bunch of money to upgrade when you know you wont get and return on your investment?

I would trade in your 325 for a 330.

[quadrophiend]

Is it not true that only a few things differ between the 2.5L and 3.0L M54 engine?

I know the cam is forged vice cast, the stroke is bigger, and the basic bottom end of the engine is different, but besides that (maybe the MAF? and some ECU variations) it's essentially the same, no?

I am not worried about reselling sometime down the line, as I have already modified to the point that it would be difficult to sell. I love my car, I just want more power. I have been considering going forced induction with the ASA Sk1 kit, but I was just considering this 3.0L tuning as another option.

If you guys say it's not worth-while, then I won't consider it any longer. I was just hoping for a cheaper route to gain some real rwhp - plus, I just generally enjoy playing around with my car with additions and modifications...

[Jeron]

The engines are almost the same but the differences are so intrinsic that modifying the engine to make it a 3.0 would be harder and maybe more expensive than just buying a 3.0 and sticking it in. But the easiest would be just to buy a new car.

Basically, I don't think you can cost effectively buy 3.0 OEM parts and put them on your engine and get any gains.

Your cheapest and most effective solution is to buy aftermarket parts made for the 2.5.

In order:
Cat back Exhaust
Intake
Header

Follow it all up with a chip tuned to the mods you have made.

If you decide to go forced induction decide now because I beleive they come with an intake and chip so you dont want to buy those and then decide later to do the forced induction.