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RalliSpec EJ25 Race Spec Series Shortblock
From $6,250.00
To $11,795.00
SKU
RalliSpec EJ25 Race Spec Shortblock
The Race Spec series short blocks are designed and built for the demands of motorsport. The foundation of the Race Spec short block is a new EJ257 block case machined and fitted with closed deck inserts to reinforce the cylinders. We fit either a factory salt bath nitiride hardened crankshaft, OEM Forged crankshaft, or ARROW Billet crankshaft. Connecting rods are 4340 tri-beam, or our 300M alloy tri-beam pro series rods. We use IRP piston with thick-wall heavy duty piston pins. The crankshaft spins in low friction ACL tri-metal bearings while connecting rods are fitted with a Calico-coated ACl for maximum durability at extreme power outputs.
Every block is assembled by our highly experienced engine technician with 20 years of Subaru motorsport engine experience. Assembly is done in our dedicated engine building room. We use highly accurate and calibrated equipment such as Mitutoyo digital micrometers, Sunnen 0.0001" reading dial bore gauges and setting fixtures, Ohaus digital scale with 1/100 of a gram accuracy, and Snap-on digital torque wrenches. Every measurement is logged and a detailed build spec sheet is supplied with each engine for your reference.
| Race Spec | RS Standard - Stage 3 | RS PRO Stage 4 | RS PRO Plus Stage 4+ |
|---|---|---|---|
| Block Case Type | EJ25 Closed Deck | EJ25 Closed Deck | EJ25 Closed Deck |
| Block Hardware | Standard | ARP | ARP |
| Pinned Mains | ✓ | ✓ | |
| Fire Lock Groove | ✓ | ✓ | ✓ |
| Bore Size | 99.75mm | 99.75mm | 99.75mm |
| Crankshaft | 79mm Hardened | OEM Forged | Arrow Billet 79mm |
| Connecting Rods | 4340 Tri-Beam | 4340 Tri-Beam | 300M Tri-Beam |
| Rod Bolts | ARP L19 | ARP 625+ | ARP 625+ |
| Pistons | IRP | IRP | IRP |
| Piston Alloy | Forged 2618 | Forged 2618 | Forged 2618 |
| Piston Pins | 0.250in | 0.250in | 0.250in w/ DLC |
| Main Bearings | Coated ACL | Coated ACL | Coated ACL |
| Rod Bearings | Coated ACL | Coated ACL | Coated ACL |
| Head Stud Threads | 14 x 2.00mm | 14 x 2.00mm | 14 x 2.00mm |
| Balance Tolerance | 1/2g | 1/3g | 1/3g |
| Compression Ratio | 8.2 (8.6) | 8.2 (8.6) | 8.2 (8.6) |
| [NOTE] All shortblocks are built to order. Allow for build and shipping time. | |||
[ Excluded From Shipping Specials ]
[ Excluded From Shipping Specials ]
WARNING: Operating, servicing and maintaining a passenger vehicle or off-road vehicle can expose you to chemicals including engine exhaust, carbon monoxide, phthalates, and lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. To minimize exposure, avoid breathing exhaust, do not idle the engine except as necessary, service your vehicle in a well-ventilated area and wear gloves or wash your hands frequently when servicing your vehicle. For more information go to https://www.P65Warnings.ca.gov/passenger-vehicle.
| SKU | RalliSpec EJ25 Race Spec Shortblock |
|---|---|
| Brand | RalliSpec |
