[mike the snake]

I'm wondering if the pistons on my 08 135 are forged as well?

I do know that visually, you can usually tell cast pistons by the raised numbers and casting seam lines, and usually forged pistons have stamped numbers, and they do look quite different on the undersides. I've built a few engines with forged pistons (coming from cast) so I know how to identify forged pistons by their appearances.

Pics would be great.

[Mike@VAC]

Ooh, nice thread. Aug 06 N54. Forged cracked cap rod, cast piston.

[ASBSECU E93]

my rod is forged

[135i]

Originally Posted by Mike@VAC

Ooh, nice thread. Aug 06 N54. Forged cracked cap rod, cast piston.

So cast pistons for all..

hmmm sucks if true. N54 is no 2JZE GTE then lol

[Mike@VAC]

[cn555ic]

Pic from E92Fan's engine rebuild
Is the pistons forged or cast?? Can you tell from pics?

[Mike@VAC]

Would like to see the inside.

I'm going to try and figure this out once and for all. We are a MAHLE dealer and even we got mixed answers.

Pistons:
Up to 7/07 - 11257561698
8/07 – 11/09 – 11257577581

I think there were at least 2 mfgrs who supplied BMW. When I worked at a large mfgr, we would sometimes change suppliers and not change the part number.

I can say, CP pistons and Carrillo rods are better than any stock components, forged or not Stronger + lighter = win.

We have sold quite a few sets of pistons and connecting rods already. Some badass N54s should be popping up soon

[MuchMoore]

Originally Posted by Mike@VAC

Would like to see the inside.

I'm going to try and figure this out once and for all. We are a MAHLE dealer and even we got mixed answers.

Pistons:
Up to 7/07 - 11257561698
8/07 – 11/09 – 11257577581

I think there were at least 2 mfgrs who supplied BMW. When I worked at a large mfgr, we would sometimes change suppliers and not change the part number.

I can't wait to hear what you find out, one way or the other.

[mithiral67]

Originally Posted by Mike@VAC

Would like to see the inside.

I'm going to try and figure this out once and for all. We are a MAHLE dealer and even we got mixed answers.

Pistons:
Up to 7/07 - 11257561698
8/07 – 11/09 – 11257577581

I think there were at least 2 mfgrs who supplied BMW. When I worked at a large mfgr, we would sometimes change suppliers and not change the part number.

I can say, CP pistons and Carrillo rods are better than any stock components, forged or not Stronger + lighter = win.

We have sold quite a few sets of pistons and connecting rods already. Some badass N54s should be popping up soon

I like this guy

[Q4P]

So a little confused here... forged rods for all and forged pistons for some; yet cast pistons for others with forged rods? That would be really odd

[Mike@VAC]

At this point I can only speak to the Aug 06 stock internals that are sitting on my desk. We are tearing another N54 down soon, need to check the date. I *think* its an 06 also

[cn555ic]

The pic of the 06 build...these are the parts that you got for the build right? They are brand new and the supplier gave you forged rods and cast piston? Hopefully you can figure this out on the other engine rebuild you guys are doing.

[Mike@VAC]

They are stock parts from an untouched Aug 06 engine that we disassembled.

[cn555ic]

Originally Posted by Mike@VAC

They are stock parts from an untouched Aug 06 engine that we disassembled.

Wow if that the case I guess there was alot of false info from the other engine rebuilds that claimed forged rods and pistons I dont know what to believe but from E92fan's pic would you be able to tell from his pics of his piston?

[TheStig]

N54 Rods Crank = Forged Pistons = Cast.

[Q4P]

Originally Posted by TheStig

N54 Rods Crank = Forged Pistons = Cast.

Aren't the pistons the most important lol? The rods look pretty damn beefy either way if u ask me and the crank is the last thing i'd be worried on an Inline 6 motor.

[TheStig]

Originally Posted by Questforpower

Aren't the pistons the most important lol? The rods look pretty damn beefy either way if u ask me and the crank is the last thing i'd be worried on an Inline 6 motor.

Lol That's what i said but hay this bitch has been eating 14/18psi here whole life and never complained. lol

[Elie335]

Originally Posted by Mike@VAC

Would like to see the inside.

I'm going to try and figure this out once and for all. We are a MAHLE dealer and even we got mixed answers.

Pistons:
Up to 7/07 - 11257561698
8/07 – 11/09 – 11257577581

I think there were at least 2 mfgrs who supplied BMW. When I worked at a large mfgr, we would sometimes change suppliers and not change the part number.

I can say, CP pistons and Carrillo rods are better than any stock components, forged or not Stronger + lighter = win.

We have sold quite a few sets of pistons and connecting rods already. Some badass N54s should be popping up soon

Thanks for sharing man! would like to know more as soon as you guys have more information

[Sigma 3]

Originally Posted by M335i Oreo Package

So the reason they changed from forged to cast in the middle of production was to keep people from running insane boost, which they knew was possible with forged pistons. Now cast pistons are now put into all of the motors (1m 335is & 335i)so that if you run excessive amounts of boost your warranty will be voided.

Sincerely,
Hanz Gruber
Director of tune detection

Originally Posted by Questforpower

Aren't the pistons the most important lol? The rods look pretty damn beefy either way if u ask me and the crank is the last thing i'd be worried on an Inline 6 motor.

Not really If I had to choose between the two I would take a forged rod. Look at how and where the forged rod cracked. One thing that has to bee considered it tune. I have seen well tuned cast component cars run amazing amount of power. Conversely I have seen forged internals fail at relatively low boost. If the timing and fueling are not where they need to be that broken rod is not uncommon.

[enrita]

This sucks big time. means my new pistons are cast now..... Should have gone for CP pistons...
Considering however how many people have run high boost for a very long period of time without issues it seems even the cast hold pretty well.

[tscdennab]

I told you from the very first post of this thread that the N54 pistons are cast. Yet everyone was so blinded by the forged piston possibility that they chose not to believe Mahle (the manufacturer) itself and they chose to hang on by the fact that there are 2 part numbers for the N54 pistons, which means nothing.

All in all, I am glad that the crank and the connecting rods are forged, it's very important to have forged rods in high torque applications. If there is no detonation due to bad tunes, the pistons should be ok and the rods should be the ones that take up all the abuse. This explains why there are N54s with close to 500whp and still going strong.

[enrita]

Originally Posted by tscdennab

I told you from the very first post of this thread that the N54 pistons are cast. Yet everyone was so blinded by the forged piston possibility that they chose not to believe Mahle (the manufacturer) itself and they chose to hang on by the fact that there are 2 part numbers for the N54 pistons, which means nothing.

All in all, I am glad that the crank and the connecting rods are forged, it's very important to have forged rods in high torque applications. If there is no detonation due to bad tunes, the pistons should be ok and the rods should be the ones that take up all the abuse. This explains why there are N54s with close to 500whp and still going strong.

well i have NO CLUE myself how to tell the difference from a cast/forged piston. My shop was definetely wrong than which made me do the WRONG decision when rebuilding the engine....