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RalliSpec EJ25 Race Spec Series 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, Manley billet crankshaft, or ARROW Billet crankshaft. Connecting rods are 4340 h-beam, 4340 tri-beam, or our 300M alloy tri-beam pro series rods. We use an RCM/Omega 2618 forged 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 or Clevite bearing for maximum durability at extreme power outputs. At minimum we suggest an 11mm ARP 625+ head stud and performance head gaskets but we also offer the 14mm RCM head studs.
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 | Basic | Standard | Pro | Pro Billet |
|---|---|---|---|---|
| Block Case Type | EJ25 Semi-Closed | EJ25 Closed Deck | EJ25 Closed Deck | EJ25 Billet/Sleeved |
| Block Hardware | OEM | OEM | ARP | ARP |
| Pinned Mains | ✓ | ✓ | ||
| Fire Lock Groove | ✓ | ✓ | ✓ | |
| Bore Size | 99.5mm | 99.75mm | 99.75mm | 99.75mm |
| Crankshaft | 79mm Nitrided | 79mm Nitrided | 79mm Manley | 79mm Arrow |
| Connecting Rods | 4340 H-STD | 4340 PRO Tri-Beam | 300M PRO Tri-Beam | 300M PRO Tri-Beam |
| Rod Bolts | ARP200 | ARP L19 | ARP 625+ | ARP 625+ |
| Omega HD Pistons | ✓ | ✓ | ✓ | ✓ |
| Piston Pins | 0.240in | 0.240in | 0.240in w/ DLC | 0.240in w/ DLC |
| Main Bearings | ACL | Coated ACL | Coated ACL | Coated ACL |
| Rod Bearings | Coated ACL | Coated Clevite | Coated Clevite | Coated Clevite |
| Head Stud Threads | 11mm | 14 x 2.00mm | 14 x 2.00mm | 14 x 1.50mm |
| Balance Precision | 1/2g | 1/3g | 1/3g | 1/3g |
| Compression Ratio | 8.2 (8.6) | 8.2 (8.6) | 8.2 (8.6) | 8.2 (8.6) |
| High Compression Option | 9.4 (9.9) | 9.4 (9.9) | 9.4 (9.9) | 9.4 (9.9) |
| [NOTE] All shortblocks are built to order. Allow for build and shipping time. | ||||
[ Excluded From Shipping Specials ]
[ Excluded From Shipping Specials ]
From $4,200.00
To $18,500.00
SKU
RalliSpec EJ25 Race Spec Shortblock
Whether race, rally, or road, RalliSpec Ltd. is dedicated to providing cutting edge solutions to your automotive performance needs. Since our inception in 1999 we have offered an unrivaled level of expertise and support to a growing list of clientele around the world. The technical partnerships we have forged with top level motorsports teams as well as our past in-house racing efforts have provided valuable insight. We pass this knowledge on to you so that the path to achieving your performance goals will be the most direct and cost effective one. While we have maintained a special focus on Subaru performance development, our experience is broad based and we are happy to assist with any high performance automotive project.
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 |