All-Billet Subaru EJ 2.5L Engine - Engine Builder Magazine

All-Billet Subaru EJ 2.5L Engine

This 2016 Subaru STi, which features an all-billet EJ 2.5L engine, was built to showcase what Kaiju Motorsports is capable of. Not only does it look great, but all expectation is that it performs well too. Check it out!

Engine of the Week is presented by

There’s always a lot to look at during the PRI Show given the countless cool parts, machines and engines to draw your attention. One car and engine bay that made me turn my head every time I passed it was Kaiju Motorsports’ 2016 STi Subaru with an all-billet EJ 2.5L engine inside. After seeing the Subaru a few times, I finally got the chance to speak with Kaiju Motorsports owner Brian Camacho about his shop and the Subaru, and it was well worth the chat.

Kaiju Motorsports is located in Henderson, NV, and specializes in JDM and imports engine work, but mainly Subaru.

Kaiju Motorsports Subaru STi

“Subarus are our go-to vehicle,” Camacho says. “That’s our heart and soul you could say. We really know the Subarus in and out. We built this car to showcase what we can do as a shop.”

Initially, the 2016 STi belonged to Brian’s office manager who bought it brand new. It came to a point where he was ready to part ways with the car, but rather than sell it, Brian saw it as an opportunity to turn it into a shop race car.

Kaiju Motorsports Subaru STi EJ engine

“We did custom graphics, 15” slicks and custom work on the fenders and hood as well,” Camacho says. “A lot of our work focuses on the engine, transmission, drivetrain, and suspension. The engine is still a 2.5L block, like what comes in the car from Subaru, but we went with a new, billet EJ 2.5L block.

“The short block came out of Australia and then IAG Performance took it, and they threw in some Darton sleeves and assembled the whole rotating assembly. Then, we paired it up with IAG Stage 5 cylinder heads, which are CNC ported and have Ferrea dual valve springs and 1mm oversized Ferrea valves on it, as well as GSC bronze valve guides. We got Brian Crower Stage 3 cams on it, and what we did at our shop, we took the cylinder block, we took the cylinder heads, and assembled the engine.”

EJ 2.5L Subaru engine

As mentioned, IAG Performance spec’d the rotating assembly, which meant a billet crank, custom rods and custom JE pistons. Brian says IAG also machined the billet block for fire rings, which help seal the block to the cylinder head, along with 14mm ARP studs. The BC Stage 3 cams are 280 duration on both the intake and exhaust.

We also mentioned that this engine bay turned some heads throughout the PRI week, and for very good reason. Not only is the car cool and the engine itself cool, but the piping for the intake and turbo really sets the whole combo off thanks to the use of titanium.

billet EJ 2.5L Subaru engine

“The turbo kit is a twin-scroll turbo manifold mated to a Garrett G42-1200 compact turbo,” he says. “From there, we took the car over to Jesse at JDL Auto in Phoenix, and he killed it with the fabrication. He used a Hypertune clamps, Ticon titanium piping and just welded it all up to perfection. He did all our intercooler piping too. He took a CSF Magnum intercooler core and made a custom intercooler, and modified our cooling system and the CSF radiator. Then, it’s got a 4” turbo back exhaust with the titanium muffler on the back. The titanium is definitely one of the things that make people stop and really pay attention to the car.”

At PRI, the STi was parked in the Exedy booth because the Subaru also features an Exedy triple-disc clutch, which Brian says is holding up the power really well.

billet EJ 2.5L Subaru engine

“We’re pushing a little over 1,000 horsepower on this engine and 700 lb.-ft. of torque,” he says. “This clutch is rated for around 750 torque and it’s holding it well. This Subaru was built to showcase all our work, but it’s very important for me to perform as well as looking really good. The car is used for drag racing.”

Helping the billet EJ 2.5L Subaru engine do its thing is a MoTeC M150 ECU and a MoTeC C127 dash to display all the right data.

Subaru STi with a billet EJ 2.5L engine

“The goal was 1,000 horsepower, so we hit that expectation,” Camacho says. “Now, as long as we could get into low 9s with the car, I’d be happy with that. If we break the 8s – amazing. But, the goal is 9s.”

Engine of the Week is sponsored by PennGrade1Elring – Das Original and NPW Companies. If you have an engine you’d like to highlight in this series, please email Engine Builder Editor Greg Jones at [email protected].

You May Also Like

Turbocharged Billet K24 Honda Engine

Noonan Race Engineering is well-known for its V8 engine platforms, but the shop has now dipped its toe into the 4-cylinder world with a billet K24 Honda engine. The objective – huge horsepower, while keeping factory creature comforts. Check it out!

In 2023, we got the chance to showcase a lot of what Noonan Race Engineering has going on inside its state-of-the-art engine and machine shop located in Spartanburg, SC. The shop was named our 2023 America’s Best Engine Shop in the Race category, and we gave people a full shop tour video of the facility, as well as showcased Noonan’s popular V8 Hemi platforms in a couple Engine of the Week features.

ProCharged 5.000” Bore Space Billet Big Block Chevy Engine

One of the first 5.000″ bore space big block Chevy engines that Visner Engine Development has come out with in this new design, this billet engine was built by Nick Bacalis of Bullet Racing Engines for a 1971 C10 belonging to Michael Rieck. Check out what 4,000-plus horsepower looks like!

billet big block Chevy engine
3,500+ HP 427 cid Billet LS Engine

At ACE Racing Engines, Stefan Rossi’s and Laura Pugh’s hard work has been paying off in the form of increased awareness and business, a new shop space out in California, and best of all, success on the track from numerous customers. Check out this excellent example of a maximum effort, billet LS engine for a drag-and-drive application.

Supercharged 388 cid LS Engine

Hoping to reach new heights in the mile, this Cadillac customer brought his car and engine in for the School of Automotive Machinists & Technology to work their magic on. See what went into the supercharged LS engine platform.

Cadillac Supercharged LS engine
Supercharged 521 cid Brad Anderson Hemi Engine

Amanda Hoover and Eddie Rogers have been campaigning their Chevelle from Hell for nearly a decade. Helping give the car its name is a screw-blown 521 cubic inch Hemi engine. Check out the details of this build done by Chris Duncan Race Cars!

Other Posts

Dave Schroeder’s 872 cid Pro Mod Nitrous Engine

Dave Schroeder and John Ens have been at the drag-and-drive game for a long time. They’ve seen a thing or two and certainly experience3d a thing or two when it comes to this category of racing, and the 872 cid Pro Mod Nitrous engine built by Reher-Morrison is a build that stands out from the

Compound Turbocharged 6.7L Powerstroke Engine

With a background in farming, Tanner Allison grew up with a passion for diesel trucks and engines. He also gravitated towards the Powerstroke platform, and has since set his sights on showing what a 6.7L Powerstroke engine can do. Check out Tanner’s most-recent diesel build!

Matt Stutzman’s 540 cid Supercharged Big Block Chevy Engine

We got a chance to spend significant time with Matt Stutzman during the 2023 PRI Show. He’s a Paralympic archer born without arms who’s now setting his sights on Top Sportsman drag racing. We caught up with him in the PennGrade1/DA Lubricants booth to get the details of his 540 cid big block Chevy engine,

Compound Turbocharged 6.0L Powerstroke Engine

Eric McMichael of McMichael’s Diesel Performance is a Ford guy through and through. His passion for the Blue Oval shines bright in his 2004 F-250, which features a compound-turbo 6.0L Powerstroke engine. Check it oit!