Technical Cons of Forged Pistons in N54??

[JonEQuest]

I am rebuilding my engine and plan to do some upgrades. I was about to order some forged rod and pistons but I have read that forged pistons expand more to heat and would cause piston slap and increased wear when the engine is cold. So basically every day when I start up. I am staying at or below 650hp so not sure now if I should do the forged pistons or not. Anyone have experience with going to forged pistons and any drawbacks? I daily this car and make a lot of small trips throughout my day so easy drive ability is a must.

 

[ShocknAwe]

If it's a DD and you're staying in the 600whp ballpark keep the bottom end as stock as possible.

Just my opinion. I'm sure others will come in.

 

[desmo11]

No cons to good pistons. I'd run Mahles.

 

[JohnDaviz]

I have read that forged pistons expand more to heat and would cause piston slap and increased wear when the engine is cold. So basically every day when I start up.

Yes. Due to the material properties 4032/2618 you need adjusted piston wall clearances.

From JE:
A 2618 piston will expand 15 percent more than a 4032 version. This, as we've mentioned, is the reason a 2618 piston requires more clearance and as a result will be slightly noisier when cold as opposed to a comparable 4032 forging.

BUT the heating of the pistons doesn´t take as long as you might think. It is not like warming up your oil.

 

[JonEQuest]

Yes. Due to the material properties 4032/2618 you need adjusted piston wall clearances.

From JE:
A 2618 piston will expand 15 percent more than a 4032 version. This, as we've mentioned, is the reason a 2618 piston requires more clearance and as a result will be slightly noisier when cold as opposed to a comparable 4032 forging.

BUT the heating of the pistons doesn´t take as long as you might think. It is not like warming up your oil.

I might just go with the 4032 piston. The 2618 JE are out of my budget anyway.

 

[JohnDaviz]

I am running the Mahle Forged 2618 pistons and as Mahle is the OEM supplier for the stock pistons this is the way to go in my opinion. You may want to check them out.

 

[ShocknAwe]

Mahle if you must. Agree with the above.