Topping off our bottom end will be a JE ProSeal cut-ring head gasket. We opted to run the stock thickness (.070) due to the increase in compression ratio from the Mahle pistons.
Here you can see the cut-rings laid out next to the gasket. The benefit of cut-rings is their impressive sealing ability. You lay the gasket down as normal and then place the triple groove cut rings on the block. When you tighten down the head the cut-rings will cut into the head creating a much tighter seal. This is especially beneficial to engines that will see forced induction. No, I’m not foreshadowing anything- this engine will stay naturally-aspirated.
We decided to get new timing chains to replace the factory chains we have that have reached almost 200K miles. It’s a great security blanket for just a few extra bucks spent at Pelican Parts.
Along with the timing chains we also picked up a new EMP-Stewart High-Performance Water pump from Pelican Parts. We’ll go more into the benefits of this water pump over the OE pump in a future “Cooling Upgrade” article.
Now that we have our shopping list done it’s time to take everything over to Pure Performance in Laguna Hills, CA to start the assembly process.
If you’ve been a reader of MotoIQ for some time then you know we’ve gone to Pure Performance for a few of our BMW upgrades, including Project E39 M5’s brake upgrade. Along with helping out with some of our BMW projects Pure Performance also builds and runs race cars in a few NASA classes and the 25 Hours of Thunderhill. With a resume like that we knew they could handle the simple task of putting our S52 together.
Once our new block was back from the machine shop sporting it’s new 86.6mm bore it was time to start the assembly. First things first as with any engine build, make it pretty!