ZSR engines

-Our first step is every new block is gone through before any machining starts. Everything has to be checked because even though they are technically "new" blocks, they are still a rough casting that can commonly have flaws. 

-Once the block is deemed usable, it is fully de-burred by hand including all the core plug holes, deck, pan rails, bottoms of cylinders, etc. Then we have taps with marked depths so all of our galley and water plugs sit the same depth in the block. Main fastener holes are bottom tapped to get as much thread engagement as possible on our main studs. All oiling modifications are done at this time as well. This is a 1-2 hour process to even get the block ready to machine. 

-The block is then resurfaced on our Berco  machine with a single CBN cutter. We find true 45* with a BHJ fixture and even the new blocks are not a true 45* and also the surface out of the box is nothing like ours. We check every deck surface with a profilometer and our surface is typically 8-18Ra. This finish will work with ANY head gasket on the market. The actual block deck height is also taken to what dimension we determine for your specific application. 

-The block is now taken to our Kwik-Way boring bar and we reference everything off of the new deck 

-Honing in our Sunnen CV616 is next. We use BHJ aluminum torque plates and either ARP studs or bolts (whichever will be used in final assembly). There is a TON of power and longevity in a proper hone finish. We again use a profilometer to check the hone surface and if someone is honing without one, they are guessing at best. The human eye really cannot detect a "good" finish vs a "poor" finish

-After installing ARP main studs, the block is line honed in our Sunnen CH100

-If we are using o-rings or fuel hoops, the block and heads are now machined for them.

​-Time for a final wash and on to assembly!

-For the rotating assembly, we measure the journals and crank stroke before any balancing is done. Same goes for the rods and pistons. Any corrections needed are done BEFORE we start balancing. All balancing is done on our state of the art CWT machine. Then we polish the crankshaft and wash all the rotating assembly parts.

​-On cylinder heads, we set all of them up, use the springs and valves required, correct any issues, bowl blend, etc

ZSR Standard Machining on ALL Engines​