STEEL CYLINDER WALLS FOR YOUR ALUSIL BLOCK: 928 Motorsports has developed a successful process for sleeving the water-cooled Porsche blocks, and has the track and race record to prove it.

UNIQUE DIFFERENCES: Although higher in initial cost than the Nikasil repair/coating of engines (which we also offer here: ), high-ductile iron cylinder sleeves offer two unique differences over a plated aluminum block:

1. Sleeving the engine to a 4" or 4 1/8" bore permits the use of standard forged pistons, with a reduction in piston cost of often over 200% from custom (metric) piston sizes.
2. Sleeving with high-ductile, high strength iron is ideal for high-boost applications (15 psi and up) where an unsupported aluminum wall will stretch under pressure and fail.
3. An inexpensive way to add displacement. Imagine taking your 100mm bore Porsche 928 5.0L motor, and by sleeving to 4.125", you now have a 5.4 liter motor, without changing your crankshaft!

Can also be used to repair deeply scratched cylinder walls and will completely renew the block.

ADDS SERVICABILITY: when an aluminum bore becomes scratched, the repair process either includes boring all cylinders to the next oversize dimension and buying all new pistons, or welding up the scratch, boring it down, and replacing the piston. Both expensive. Should a steel sleeve become scratched, the sleeve can be pulled out and a new one installed. Much less expensive!

O-RINGING and HEAD GASKETS: The custom T-top on the 928 Motorsports engine sleeves provides the ideal location for a stainless steel or copper o-ring that will provided a positive seal on the head gasket fire ring against any amount of boost. The heads do not need to be modified with this design.

OUR BLOCK SLEEVING SERVICE:

• Ship your bare block to us at 928 Motorsports, LLC. Prepare your block by removing all the steel from the piston decks, like locating pins and head studs. Send just the bare block, no crank or rods installed. If there are steel parts in the block deck that you cannot remove, they will be removed for you but you will be charged extra for this service. The block does not have to be clean.
• Let us know what your plan for Pistons is. We can build your engine for stock 100mm bore, 104mm bore, 4.0" bore, or 4 1/8" bore. The pistons should be shipped to us with the block so we can match-fit.
• The price in this listing covers the standard 6-part process:
  
1. Bore the block to hold the sleeves.
2. The whole block is heated in to an oven and then the sleeves are pressed into place.
3. The cylinder walls are honed to match the pistons.
4. The decks are planed for flatness
5. The o-ring grooves are cut into the top of the sleeves.
6. The finished block is tanked for cleansing before it is shipped. The cylinder walls will be lightly oiled to prevent surface rust and the block will be closed in a heavy engine bag for shipping.