Quantum Quality

All of our engines are built in house at our Fredonia, WI facility. The machine work is also done locally to our custom specs. Since the engines are hand built by us we can adjust tolerances and part choices as needed for our customers. Example - Want to upgrade your rod bolts in one of our staged engines? No problem, anything can be custom tailored for your new engine. 

 

 

Engine Builds

We can build you your dream engine right here at Quantum Performance. We build everything from Subaru EJ engines to VQ series Nissan/Infiniti engines to domestic GM 350's and Ford 302/347 Strokers. Call or e-mail us today for more info!

 

 

Subaru


OEM Replacement

Contact us for the most up to date pricing on a genuine Subaru replacement short block. 


IAG Performance Engine’s


Quantum Performance is a certified IAG Performance installer. If you purchase an IAG Engine through us and have it installed by Quantum Performance we are able to offer IAG’s 2 year Engine Extended Warranty. Quantum Performance will walk you through the process and help you choose the right block that fits your power and usage goals.

 

Stage 1

Quantum Performance Stage 1 EJ257 performance shortblocks are designed to eliminate the most common issue of the EJ257: the factory ring land failure. A great upgrade for the WRX, LGT and FXT owners, or for the mild to moderately built STI looking for more security. Utilizing Manley's Turbo-Tuff forged pistons (Forged and Machined in the USA) to prevent failure, you get the all the benefits of the STI without the main weak point.

Estimated Power Rating: 350-400 WHP / 350-400 WTQ

 
 
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Includes the following:
- New 2015 EJ257 Parts:
    - Case halves, Genuine Subaru OEM Seals, and bolts
    - Nitrited Crankshaft
    - STI Connecting Rods
- Manley Performance Turbo Tuff Forged Pistons - Teflon Coated Skirts
- Total Seal Piston Ring Kit, Napier 2nd Ring and High Tension Oil Rings for Improved Oil Control
- King Main and Rod XP Race Bearings
- Bores honed for rings
- Rotating assembly balanced (+/- less than 1 gram)
- Engine cleaned, blueprinted, clearanced, pin fitted, and assembled with Red Line assembly lube.


 

Stage 2

Quantum Performance Stage 2 EJ257 Performance Short-blocks are our most popular EJ257 platform, offering extra holding power for more heavily modified needs. Similar to our Stage 1 short-block, these engines also utilize the same high quality forged piston. Additionally, we go one step further to incorporate Manley's H-Beam H-Tuff connecting rods (Forged and Machined in the USA) with ARP 2000 rod bolts. The OEM STI connecting rods tend to give way under higher loads (typically around 400wtq), but our Stage 2 setup firms this up and gives you peace of mind. Combined that with the Nitrated crankshaft and custom toleranced King XP Race Bearings, and you are set for a solid bottom end that can handle most heavily modified setups.

 

Estimated Power Rating: 450-500 WHP / 450-500 WTQ

 

Includes the following:
- New 2015 EJ257 Parts:
    - Case Halves, Genuine Subaru OEM Seals, and Bolts
    - Nitrited Crankshaft
- Manley Turbo Tuff Forged Pistons - Teflon Coated Skirts
- Manley 4340 Forged H-Tuff H-beam Rods - ARP 2000 Rod Bolts
- Total Seal Piston Ring Kit, Napier 2nd Ring and High Tension Oil Rings for Improved Oil Control
- King Main and Rod XP Race Bearings
- Bores honed for rings
- Rotating assembly balanced (+/- less than 1 gram)
- Engine cleaned, blueprinted, clearanced, pin fitted, and assembled with Red Line assembly lube.

 


 
 

Looking for builds exceeding Stage 2?

Contact us to discuss the options for custom builds.