If you've spent any time in the Mitsubishi tuner scene, you know that the 4g64 vs 4g63 debate is one of those topics that never really goes away. It's the kind of thing people argue about over open hoods at car meets or in the deep corners of old forums that haven't been updated since 2008. At first glance, they look pretty similar, but the way they deliver power—and what you have to do to make them fast—is actually quite different.
The 4G63 is the undisputed king of the "Evo era," the engine that put Mitsubishi on the map in the rally world and made the Lancer Evolution a household name for gearheads. Then you have the 4G64, which is often dismissed as the "SOHC economy engine" found in Galants, older Eclipses, and even some forklifts. But as many builders have discovered, the 4G64 has a secret weapon: displacement.
The Displacement Game: 2.0L vs 2.4L
The most obvious difference when looking at the 4g64 vs 4g63 is the size. The 4G63 is a 2.0-liter engine, while the 4G64 bumps things up to a 2.4-liter. In the world of four-cylinders, that extra 400cc is a massive jump.
The 4G64 gets this extra volume through a combination of a larger bore (86.5mm vs 85mm) and a longer stroke (100mm vs 88mm). Because the stroke is longer, the 4G64 block is actually about 6mm taller than the 4G63 block. This is why you'll often hear people refer to the 4G64 as the "tall block."
Why does this matter? Well, torque. There's no replacement for displacement, as the old saying goes. A 4G64 is going to feel a lot punchier at low RPMs. It gets a heavy car moving much easier than the 2.0L does. On the flip side, the 4G63 is a rev-happy beast. Its shorter stroke means the pistons aren't traveling as far up and down, which reduces stress at high RPMs. If you want an engine that screams to 9,000 RPM, the 4G63 is usually the easier path.
Why People Love the 4G63
There is a reason the 4G63 is a legend. It was built from the factory to handle boost. If you find a 4G63T (the turbo version), it comes with oil squirters to keep the pistons cool, a beefy crank, and a head that flows incredibly well right out of the box.
The aftermarket support for the 4G63 is also insane. You can find everything from mild street cams to crazy billet blocks capable of holding 1,000+ horsepower. Because it was the flagship performance engine for Mitsubishi for decades, the "recipe" for making power is well-documented. You don't have to guess; you just follow the path that thousands of Evo owners have taken before you.
The Appeal of the 4G64 (The "Frankenstein" Build)
So, if the 4G63 is so good, why bother with the 4G64? Most people aren't actually using the 4G64 in its stock, single-overhead-cam (SOHC) form. Instead, they're building what's known as a "G464 Hybrid" or a "2.4L swap."
This involves taking the 2.4L block from a Galant or an Eclipse and slapping a DOHC head from a 4G63 on top. Suddenly, you have the high-flow characteristics of the Evo head paired with the massive torque of the 2.4L bottom end.
This setup is a monster for street driving. When you compare a hybrid 4g64 vs 4g63 in terms of turbo lag, the 2.4L wins every time. It can spool a large turbo much faster than the 2.0L can. If you're running a big Precision or Garrett turbo that would normally be "laggy" on a 2.0L, the 2.4L wakes it up much earlier in the rev range. It makes the car feel much more responsive in traffic and when pulling out of corners.
Technical Hurdles and Reliability
It's not all sunshine and rainbows with the 2.4L swap, though. Since the 4G64 block is taller, you run into some fitment issues. Your timing belt setup gets a bit weird (you usually need a specific combination of gears and belts), and your downpipe might sit slightly lower than it would on a 4G63.
There's also the issue of the rod-to-stroke ratio. Because the 4G64 has such a long stroke, the side-loading on the cylinder walls is higher. If you try to rev a stock-geometry 4G64 to 8,500 RPM every day, you're probably going to have a bad time. Most builders who want the best of both worlds go for a "long rod" 2.4L setup, which uses custom rods and pistons to improve the engine's geometry, but that adds a lot of cost to the build.
The 4G63, by comparison, is much more "plug and play." If you're starting with an Evo or a DSM (Eclipse/Talon), the 4G63 just fits. You don't have to worry about deck height, custom timing components, or weird oiling issues. It's a proven, reliable platform that can take a beating.
Which One Is Better for You?
Choosing between the 4g64 vs 4g63 really depends on what you want to do with the car.
Go with the 4G63 if: * You want a high-revving engine that loves to scream at the top end. * You're looking for the simplest, most documented path to 400-600 horsepower. * You do a lot of track days or drag racing where you'll be staying in the high RPM range. * You want to keep things "original" or don't want to deal with the headaches of custom hybrid builds.
Go with the 4G64 (Hybrid) if: * You want a "torquey" street car that feels fast even when you aren't redlining it. * You plan on running a very large turbo and want to minimize lag. * You have a lower budget for the initial block (4G64 blocks are usually much cheaper at junkyards than 4G63T blocks). * You enjoy the "building" aspect and don't mind measuring twice and cutting once to get everything to line up.
The Cost Factor
In the past, the 4G64 was the "budget" way to get more displacement. You could pick up a block for $200, grab a used Evo head, and have a 2.4L beast for a fraction of what a stroker kit for a 4G63 would cost.
However, as these engines get older and rarer, the price gap is closing. Everyone knows about the 2.4L swap now, so the days of finding pristine 4G64 blocks for peanuts are starting to fade. Still, if you're building from scratch, a 4G64 block is almost always going to be more affordable than a genuine Evo 4G63 block.
Final Thoughts
At the end of the day, the 4g64 vs 4g63 choice comes down to personality. The 4G63 is the precision instrument—the high-strung, rally-bred heart that defines the Mitsubishi brand. It's reliable, it's fast, and it sounds incredible at 8,000 RPM.
The 4G64 is the brute. It's the torque-heavy powerhouse that makes a four-cylinder feel like a much larger engine. It takes a little more work to get it "right," but once you feel that low-end surge of power and the way it wakes up a big turbo, it's hard to go back to a 2.0L.
Whichever way you go, you're getting one of the best engine architectures ever designed. Both blocks are incredibly stout, and both have the potential to embarrass much more expensive cars on the street or the strip. Just make sure you know what you're getting into before you start bolting parts together!