side by side m52 alum. vs. iron block weight

[charlie2309]

Had these sitting side by side on my shelf, so thought I'd weigh them just to see definitively what the real weight difference is between the aluminum bblock and iron block m52. I know there has been plenty of weights posted all over for these engines fully dressed, but I always wanted to see two stripped blocks weighed on the same scale, same day, for my own eyes.

For the record, the iron block is an m52b28 pulled from an e39, the aluminum block is also an m52b28 pulled from a 97 z3. Neither have any rotating assembly, are stripped bare.

-First the scale by itself
-Then the scale with some 2x4 blocks arranged to support the
blocks while weighing
-Iron block on the left, aluminum on right
-Aluminum first
-Iron block finishes it up

So, this is a cheap scale, it could be off by a couple pounds. But to me the important thing is not what each block weighs, but the difference between the two, which should be pretty accurate based on same scale, same method.
The figure I've been hearing tossed around for weight savings of the aluminum over iron block has been 60lbs. Based on this side by side comparo it looks to be more like 52 lbs. I apologise if the weights are difficult to read in the pics. In person I read 106 on the iron block, 54 on the aluminum. Adjusted for my platform this would be 103, and 51 lbs.

[Beej '86 325es]

Nice. I always wondered what the weight difference actually was. Thanks for posting this.

[charlie2309]

Yeah, thank you. I've wondered about this a lot.

[Bimmian89]

Nice, that's a pretty big difference didn't think it was that much. Good stuff man

[nando]

damn, big difference! I have an S52 block in the garage for mockup, that thing is a heavy bastard to move around..

[2mAn]

this makes me very excited! I cant wait to see what my car weighs after the aluminum block swap. It was at 2400lbs with the M20, full tank, full interior

[charlie2309]

this makes me very excited! I cant wait to see what my car weighs after the aluminum block swap. It was at 2400lbs with the M20, full tank, full interior

I've been following your build, you are doing the exact setup that I had been planning until I elected to go m60. Hoveringuy swears by the aluminum block setup for chassis balance. Well done 2man! 2400 with full interior is awesome, should be very similar with the alum. m52.
I am working on a diet plan for my m60 arrangement.

[2mAn]

I drove hoveringuy's car and its amazing. I was torn between alu M52 and a M54, but since I knew I would end up back in CA a M54 wouldnt fly so I had to pass. Im still happy with my decision.

Glad you're following the build, seems like the only people following are the ones bitching about random things! haha

[Gleb]

Does everything else weigh pretty much the same on alum M52 vs S52?