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We feel that the OEM 7" wide wheels and 215mm Prius tires are extremely undersized and underwhelming, but after upgrading to a 17x9" wheel and aggressive 255/40/17 street tire these things can make huge grip. The stock ride heights are also a bit too tall and the spring rates too soft for any serious track use, so we tend to go straight to coilovers (like those from MCS) and firmer spring and damping rates, then add our spherical top mount camber plates up front for alignment and handling adjustments. We've also have had good results installing Whiteline bushings and swaybars, among other solutions.
Anyway, the 86 is a neat little chassis, which can be made to handle very well with the right parts, and with an upgrade to better track brake pads/lines/fluid they stop like a beast on track as well. Read our BRZ project build thread for more on our thoughts about the brakes and suspension, which we won't really cover in this thread.
This thread is not about: suspension, wheels, tires or handling. What we are covering here is a better choice of POWER PLANT for the 86
After those non-power things are addressed, our number one beef with the Scion FR-S and Subaru BRZ has to do with the goofy drivetrain it comes with. Yes, goofy is the only way to describe the flat-four engine in these cars. The engine that comes in these things is a giant headache with very limited potential and questionable reliability when modified.
What's So Wrong With The Subaru FA20 Boxer Engine?
We aren't picking on all Subaru engines, just this one. It isn't that much of a hindrance in low speed autocross competition (these cars are doing very well in C Street and STX classes!) but the deficiencies of the FA20 quickly becomes apparent on a road course. These cars are what you'd euphemistically call "momentum cars"... since they don't make nearly enough horsepower for the weight of the chassis, once you try to get going above about 30 mph. I say the same thing about all stock-engined Miatas, among other cars. These momentum cars are better suited running with the Miata run group on a road course, as the Mustangs, Corvettes, 911s and other powerful cars are going to be flying by your FT86 (if those other guys have a good driver, of course - no amount of power can make up for a lack of talent!)
The Subaru built FA20 / Toyota 4U-GSE 2.0L "flat-4" (aka: boxer) direct injected 200 hp engine that comes in these cars is a novel piece of engineering, I suppose. It has a "low center of gravity" layout and all that, but it is also a staggering 31" wide. This is really one big ass little engine. It is so wide that the frame rails had to be pushed way out there, but even so the clearance between the cylinder heads and the frame is tight. I suppose you can remove the spark plugs without pulling the engine, but it looked tight. This layout reminds me of Porsche 911 repair nightmares (which has a similarly wide flat-6 engine).
The engine block is short front-to-back (only 18" long) but it is placed in the engine bay way too far forward. So far, in fact, that more than 1/2 of the mass of the engine is in front of the front axle centerline. This is very strange, and I cannot say why the Subaru and Toyota engineers that designed this chassis and drivetrain placed the engine so far forward. They even had to use an extra long bellhousing and a crazy long shifter extension on back of the transmission to get the gear shift lever far enough rearward to mate up with the driver in the cockpit. My calibrated engineer's eyeball says this stock motor could be moved back by another ~10", which would help the front to rear weight balance significantly; in stock form we measured 56% of the weight on the front wheels, and our Alpha tester's modded FR-S has a 55%F/46%R weight bias.
Rick's FR-S came to us with a turbo kit, StopTech BBK, rear seat removed, a 4-point roll bar and racing seats installed, weighing 2682 lbs
So the engine is super wide, and fore-aft engine placement of this lump is not great - it could have been improved with just a little bit of effort. In my opinion this car was really built from a lot of older carryover Subaru parts and technology... Subaru GR design in the back, some Subaru GD front suspension design, a traditional forward biased engine layout (things like the starter, that sits way up high and would have interfered with the firewall if it was set back, would have had to be redesigned and moved down below), and all wrapped in some pretty new bodywork. Hey, it is economics, I get it... to totally design a 100% all new RWD coupe from scratch would have cost so much more, and that would have driven up the car's price. One of the saving graces of this chassis is the low cost: The FR-S starts at $24,500 sticker and the Subaru BRZ starts at $25,495.
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