Assembling the Block and Heads

Update by Alan Cesar to the Subaru Impreza WRX project car
Jun 26, 2013

Our used replacement heads will seal well with the Cometic multi-layer steel head gaskets. We got a complete Cometic gasket set to keep all our fluids separated.
The pistons are installed after the rotating assembly is in place, but before the heads go on. The piston pins go in through service ports in the side of the block.
To complement our ARP case bolts, we got the head studs too. These will allow us to put much more torque on the heads, which will help keep the boost inside.
After machining and cleaning, our used replacement heads look fantastic with Supertech valves installed.
Finally, it's time seal it all up. We can close off the case with our baffled, deep-sump oil pan from Moroso.

With the rotating assembly put together and the ARP hardware installed, our engine was ready for heads. Throughout this process we’ve been using the Cometic gasket set, but now we get to the pièce de résistance of their kit: their multi-layer steel head gaskets. These are stronger than the stock gaskets, so it’ll handle high temperatures and boost more readily.

We want reliability in this build, because we never want to open this engine back up again. That’s also why we installed Supertech‘s valves when we had the head work done. The stainless steel valves on the intake and inconel on the exhaust will better stand up to higher combustion temperatures. We also used Supertech’s valve guides.

Finally, we know we had oil starvation issues. To battle that, we got a baffled, deep-sump oil pan from Moroso along with their beefed-up oil pickup tube. This should keep our bearings happy during those high-G maneuvers.

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