Whether you are looking to upgrade your existing Subaru drivetrain or replace your old engine that’s had it, AMS offers a number of Subaru EJ25 Short and Long Block Stages to support any current or future demands you may have for your Subaru vehicle.

All AMS Subaru short and long block assemblies use only the highest quality components to ensure maximum strength, power and reliability. Each block is checked for correct dimensions, cylinder bore, mains and block flatness – then hand assembled at AMS using the same exacting care as in our championship winning race engines.

AMS SUBARU STI EJ25 SHORT BLOCKS

STAGE 1 (info)

* JE Pistons
* Stock forged STi rods
* Brand new short block
* High performance rod & main bearings
* Precision AMS spec machine work on block & crank
* Precise, documented hand assembly

STAGE 2 (info)

* JE Pistons
* Manley H-beam Rods
* Brand new short block
* High performance rod & main bearings
* Precision AMS spec machine work on block & crank
* Precise, documented hand assembly

STAGE 3 (info)

* JE Pistons
* Manley I-beam Rods
* Billet crank
* Brand new sleeved short block
* High performance rod & main bearings
* Precision AMS spec machine work on block & crank
* Precise, documented hand assembly

Available Options

AMS can customize your stage 1 through 3 short block package with a number of options including JE Billet Pistons, full gasket sets, an 08 STI High Volume Oil Pump, Subaru water pump and gasket set, timing belt and tensioner, ARP head studs, and rod upgrades. Click on each stage above for available options.

AMS SUBARU STI EJ25 LONG BLOCKS

STAGE 1 (info)

* JE Pistons
* Manley H Beam Rods
* Brand new short block
* Cosworth Heads
* GSC Cams
* New OEM head gaskets
* High performance rod & main bearings
* ARP Head Studs
* Precision AMS spec machine work on block & crank
* Precise, documented hand assembly

STAGE 2 (info)

* JE Pistons
* Manley H Beam Rods
* Billet crank
* Cosworth Heads
* GSC Cams
* New OEM head gaskets
* High performance rod & main bearings
* ARP head studs
* Precision AMS spec machine work on block & crank
* Precise, documented hand assembly

STAGE 3 (info)

* JE Pistons
* Manley I Beam Rods
* Billet crank
* Sleeved block
* Cosworth Heads
* GSC Cams
* New OEM head gaskets
* High performance rod & main bearings
* ARP head studs
* Precision AMS spec machine work on block & crank
* Precise, documented hand assembly

Available Options

AMS can customize your stage 1 through 3 short block package with a number of options including JE Billet Pistons, full gasket sets, an 08 STI High Volume Oil Pump, Subaru water pump and gasket set, timing belt and tensioner, ARP head studs, and rod upgrades. Click on each stage above for available options.

The AMS Subaru STI Stage 1 long block is the ultimate solution for high horse power reliability. We use only the best off the shelf and custom designed AMS spec components. Combine that with the latest in machine and assembly practices and you are assured only the best!

All our engines are hand assembled at AMS using the same care as the engine in our 1142 awhp, world record holding AMS Drag EVO. Every motor is balanced, blueprinted and assembled to AMS’ exacting standards.

Before assembly each block is checked for correct dimensions, cylinder bore, mains, block flatness, etc… to ensure you get the best foundation for your new engine. Every engine we assemble has a build sheet where tolerances, torque specs, and clearances are documented.

ARP has just released a new Pro Series ARP2000 main stud kit for 2008 and later Mitsubishi 2..0L (4B11) Turbo and Non Turbo applications. Part No. 207-5403 includes a set of ten, M10 ARP2000 main studs, a set of ten, M8 ARP2000 main studs, twenty 8740 chrome moly steel 12 pt nuts and a 1/2 oz. pack of ARP Ultra-Torque fastener assembly lubricant. All Pro Series ARP2000 studs are centerless ground, heat treated prior to thread rolling and machining, and are nominally rated at 220,000 psi. These fasteners deliver a 50% increase in tensile strength over the OEM main bolts.

Product: Main Stud Kit
Application: Mitsubishi 2.0L (4B11) Turbo / Evolution X
Part #: 207-5403

ARP has just released a new Pro Series ARP2000 connecting rod bolt kit for BMW 2.8L (M52EURO), 3.0L (S50US) and 3.2L (S52US) inline 6 cylinder applications. Part No. 201-6201 includes a set of twelve ARP2000 Pro Series rod bolts that are rated at 220,000 psi and replace the BMW factory bolt part no#11241739728. The ARP2000 material has considerably better fatigue life and the bolts are reuseable as compared to the OEM Torque To Yield (TTY) rod bolts which must be replaced after each use. Optimum design, enhanced reliability and increased strength are the main attributes of ARP’s Pro Series connecting rod bolts.

Product: Rod Bolt Kit
Application: BMW 2.8L (M52EURO) 3.0L & 3.2L (S50/S52US)
Part #: 201-6201