All MWR 2ZR-FE built short blocks include:
– ARP main studs
– Wiseco forged pistons
– MWR main and rod bearings
– Expert machine work, inspection and assembly
1. Compression ratio
Choose 9.0:1 compression for turbo, supercharged or extreme nitrous applications. Choose 12.0:1 for naturally aspirated performance with the ability to run a small shot of nitrous.
2. Connecting rods
Select stock connecting rods for naturally aspirated engine combinations. For turbocharged, supercharged or nitrous applications we recommend upgrading to MWR or Crower billet connecting rods for additional safety and strength.
3. Core charge
Like most engine builders we sell these engines, heads and blocks on an exchange basis. That means that we require you to send us a rebuildable “core” similar to the engine, head or block that we are sending to you. If we’re going to send the rebuilt unit to you first then we charge you a core charge, which is a deposit that we hold on to until your core is returned to us and is then refunded to you. For a full refund of your core charge the core must be returned within 30 days and must be rebuildable- this means no holes or cracks in the block, no significant damage to cylinder heads, and no missing bits such as cam caps. We don’t care about pistons or rods. Valves may be bent, crankshafts may be scuffed.
If you choose the Lightened and Knife Edged option the crankshaft is precisely machined to remove approximately 10% of its weight, then the counterweights are contoured and the crankshaft is rebalanced. Advantages include quicker throttle response, horsepower increase thanks to less drag through crank case oil, and corresponding reduction in oil foaming. Great for high rpm and racing applications.