Aluminium M52 Z3 Casting

[BenGerman]

Morning Gents,

A quick question in regards of the 98-98 Z3 Aluminium Block with Steel liners.

Can anybody confirm for me if the casting number (intake side centered) on these blocks is 1 432 219?


Thanks in advance!

[mjweimer]

Morning Gents,

A quick question in regards of the 98-98 Z3 Aluminium Block with Steel liners.

Can anybody confirm for me if the casting number (intake side centered) on these blocks is 1 432 219?


Thanks in advance!

I can look at my pic archive later today to see if I have a shot of the block or see if it is visible in the car....someone else might chime in meanwhile.

[2mAn]

Looks like it

[BenGerman]

Perfect, thanks so much.

https://www.r3vlimited.com/board/forum/e30-technical-forums/24v-engine-swaps/m50-52-s50-52/340737-m52-aluminium-blocks

Confirms the thoughts from in here.

Seems like early euro E36 blocks use the same casting. Plenty of them around. Guess there is only one way to find out if the M52B20 uses the same size liners as the M52B28 - making some chips.
Did you overbore yours to 84.25-84.5mm or just get a fresh hone?

[Chilezen]

If I remember correctly, some euro blocks have Alusil (or something like that) liners instead of steel; avoid those blocks. Easiest way to tell is with a magnet.

I had my alloy block rebuilt, and the builder recommended I don't bore it, just hone it. That's fine because he said it was in good condition, and I wouldn't have to buy new pistons.
But I know you can bore it, I know a builder does build and sell a performance kit and it's worked well in his cars. Look up Metric Mechanic if you're interested.

[mjweimer]

I left the bottom end alone on my build (114k engine). It still showed an excellent cross-hatch pattern on the sleeves and a leakdown + compression test only showed issues with a couple of intake valves. Went through the head; very light skim + 5 angle valve & seat and rebuild the lifters. Just a simple NA motor so it was great for my plans.

Pics from disassembly, this is how it looked after pulling the head....the deck and the light carbon at the top of the bores cleaned up easily






I'd just hone it if doing new rings, can't comment on the ability to bore or how far you can go before compromising the sleeves. Looks like Simon had some work done to his...

[BenGerman]

If I remember correctly, some euro blocks have Alusil (or something like that) liners instead of steel; avoid those blocks. Easiest way to tell is with a magnet.

I had my alloy block rebuilt, and the builder recommended I don't bore it, just hone it. That's fine because he said it was in good condition, and I wouldn't have to buy new pistons.
But I know you can bore it, I know a builder does build and sell a performance kit and it's worked well in his cars. Look up Metric Mechanic if you're interested.

The Alusil blocks are Casting number 1 748 450. Most of the European M52s use that block. The idea to look for the casting numbers came from the video in the thread I posted above.

I have found a bunch of 1 432 219 Blocks, but they are all M52B20. I will take a shot and grab a couple to put in my next touring, as they are cheap to get.

My thought process is that it’s highly unlikely that BMW had two different castings for M52B20 and B28, especially since the casting numbers themselves match. Most likely they were just bored to 80mm for B20 and 84mm for B28.
Buying a dirt cheap B20 block and having it bored / honed to 84mm is still a lot cheaper than trying to find an Aluminium M52B28 in the US these days, especially since I won’t need the Crank, rods or pistons.

Here is a picture of a M52B20 E36 block I bought.

[Chilezen]

I can confirm that my M52B28 block is 1 432 219.

I've never heard of an aluminum M52B20 block in the US. Are you in the US?

I agree that the B28 blocks are hard to find, being only in 1 car for two years. But there is a Z3 with that engine at my local junkyard (here in California). So that's a little exciting if anyone wants one.

[BenGerman]

I’m in the US, but have a Touring coming from Germany.

[pazi88]

The Alusil blocks are Casting number 1 748 450. Most of the European M52s use that block. The idea to look for the casting numbers came from the video in the thread I posted above.

I have found a bunch of 1 432 219 Blocks, but they are all M52B20. I will take a shot and grab a couple to put in my next touring, as they are cheap to get.

-450 is nikasil. Not alusil. Alusil was used in m62. The -450 nikasil blocks don't need to be avoided, because in most of the cases those show up no real wear at all and if you can use the block as it is (the point of the nikasil is that it's really wear resistant). Those handle boosting etc. just fine. But if you want to overbore the block etc. then you need sleeved -219 block.