Every 4G63 build on the road traces back to a cooperation between Chrysler and Mitsubishi. Chrysler needed small cars it didn't have to design. Mitsubishi needed a way around U.S. import quotas. What came out the other side was a 2.0L iron-block turbo four and an AWD coupe cheap enough that high schoolers could buy one.
Here's the actual history, generation by generation, and what it means if you've got one in the garage right now.
How Diamond-Star Motors Got Its Start
Diamond-Star Motors was a 50/50 joint venture between Chrysler and Mitsubishi Motors, formed in October 1985. The name is literal: the three diamonds from the Mitsubishi logo, the Pentastar from Chrysler, you get it.
Ground broke in Normal, Illinois in April 1986. The plant, roughly 1.9 million square feet, about $650 million to build, rated for 240,000 cars a year, was finished in March 1988. Mitsubishi ran the floor. Mitsubishi supplied the engines and transmissions. Chrysler got badges, dealer network, and a look inside Japanese production methods.
The partnership didn't last long. Chrysler, cash-strapped coming out of the 1990–91 recession, agreed in October 1991 to sell its half to Mitsubishi for $99.75 million. The equity transfer finished up in 1993, and on July 1, 1995 the plant was formally renamed Mitsubishi Motor Manufacturing of America. Diamond-Star Motors was no more. DSM, the enthusiast term, was just getting started.
1G (1990–1994)
Three cars, one line, one platform: Mitsubishi Eclipse, Eagle Talon, and the Plymouth Laser. Same chassis, different noses, different badges, wildly different resale conversations today.
The lineup ran from genuinely slow to genuinely quick:
- Base / GS: 1.8L 4G37 SOHC, 92 hp. The one your aunt had.
- GS DOHC / Talon ES / Laser RS: 2.0L 4G63 naturally aspirated, 135 hp.
- GS-T / Talon TSi / Laser RS Turbo: 4G63T, front-wheel drive.
- GSX / Talon TSi AWD / Laser RS Turbo AWD: 4G63T, all-wheel drive. The one everyone actually wants.
Power on the turbo cars: 195 hp and 203 lb-ft with the 5-speed (the 1990 FWD GS-T was rated 190 before both turbo models standardized at 195 for 1991), and 180 hp with the automatic, which got smaller injectors and the smaller 13G turbo instead of the manual car's 14B. Compression was 7.8:1 because Mitsubishi was building headroom for boost, not chasing a spec sheet.
There were two eras for the 1G: 1Ga (1990–92) with the pop-up headlights, and the 1Gb (1992–94) refresh with updated sheetmetal and fixed lights. Same bones, different headlights.
The part that still drives buying decisions: 6-bolt vs 7-bolt
The 6-bolt/7-bolt thing refers to how many bolts hold the flywheel to the crankshaft, and it's shorthand for two different bottom-end designs.
Mitsubishi made the changeover around April 1992. So:
- 1990 to roughly 1992.5: 6-bolt. Bigger rods, larger crank bearing journals, the bottom end that built the platform's reputation.
- 1992.5 to 1994: 1G 7-bolt, still wearing the 1G head. Less common, and often confused with the later 2G motor. It isn't the same thing.
If you're shopping a '92, don't take the ad's word for it. Check the block. Sellers get this wrong constantly, and the 6-bolt-specific main bearings and hardware aren't interchangeable with what a 7-bolt needs.
2G (1995–1999): Smoother, Faster, More Controversary
The 1995 redesign killed the pop-ups for good, dropped the Plymouth Laser entirely, and pushed the styling toward something rounder and more mainstream. Two nameplates left: Eclipse and Talon.
On the turbo cars (GS-T, GSX, Talon TSi / TSi AWD), the 4G63T got a real rework:
- Compression up to 8.5:1 from 7.8:1
- Garrett T25 turbo at about 12 psi, replacing the 14B/13G Mitsubishi units
- 210 hp @ 6,000 rpm and 214 lb-ft @ 3,000 with the manual (205/220 on the automatic)
The intent was less lag and more midrange for a mass-market buyer, and it worked. The tradeoff is the part tuners fixate on: the 1G head and intake tract were built around air volume, the 2G's around air velocity. Great from a stoplight. A ceiling you hit sooner once you're chasing real power.
On the non-turbo cars, the engine changed suppliers. RS and GS models got the 420A, a Chrysler-built 2.0 DOHC, no balance shafts, unrelated to the 4G63. Fine motor. Not a DSM motor in the way people mean it.
Other 2G notes worth knowing: the Spyder convertible arrived for 1996 (GS and GS-T only, there was never a GSX Spyder), the 2Gb facelift landed in 1997, the Talon died after 1998 along with the Eagle brand, and 1999 was the last year for a turbo AWD Eclipse. The 3G that followed in 2000 was front-drive with a V6. The DSM era ended there.
Crank walk, honestly
You can't write about 2G without it. Crank walk is thrust bearing wear that lets the crankshaft move fore-and-aft and left alone, it takes the block with it. It's associated with the 7-bolt bottom end, and it hit hardest in the mid-'90s cars.
What's fair to say: it was a real design weakness, Mitsubishi quietly revised the crank and moved to a split-type thrust bearing for 1998–99, and the internet has spent twenty years arguing about how common it actually was. Plenty of 7-bolt cars have run hard for decades untouched.
What we tell people who call us: it's not a reason to write off a 2G, but it is a reason to understand the cars' history and what you may be getting yourself into; and a reason to sort your clutch, hydraulics, and release bearing properly, since a dragging or overloaded release setup pushes on the crank every time you're at a light. If you're already in the block, ACL and King race bearings and main studs are the cheap part of that job.
Why the 4G63 Outlived the Badges
Diamond-Star folded, the Talon and Laser went away, but the engine survived. The same basic 4G63T architecture carried the AWD Galant VR-4 and then the Lancer Evolution from I to IX in 2006, where it picked up MIVEC, a mirrored layout in the engine bay, and a factory rally program's worth of development.
That's the reason a 30-year-old economy coupe still has a parts catalog this deep. The aftermarket didn’t develop for the Eclipse. It got built for the 4G63, and the Eclipse, Talon, and Laser were the cheapest way in.
It's also, plainly, where we started. Some of MAP's first customers were DSM guys, and 4G63 parts are still a core part of what we stock: 1G and 2G specific right alongside Evo 8/9 and Evo X.
If You Own One Right Now, Start Here
These cars are 27 to 36 years old. The build wish list matters less than the stuff holding it together.
Maintenance first, and it's not negotiable. The 4G63 is an interference engine, a snapped belt bends valves. Timing belt, tensioner, and water pump get done together, on schedule, with known-good parts. Same conversation for gaskets and seals, radiators and cooling, and 30-year-old motor mounts that have long since turned to pudding. Plenty of the OEM Mitsubishi part numbers are still available. We stock a lot of them because we know people need still need them.
Then the supporting mods, in the order that actually makes sense. Fueling and airflow before turbo: injectors and a fuel pump, then intercooler and exhaust. A bigger turbo and manifold on a stock fuel system is not something we’d recommend.
Then the hardware, if you're going past stock power. Head studs, head gasket, rods and pistons when you’re going for considerably more power. The stock bottom end handles more than people expect; the head gasket usually taps out first.
Full catalog lives here: 1G & 2G DSM parts →
DSM FAQs
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What does DSM stand for? Diamond-Star Motors, the Chrysler/Mitsubishi joint venture (1985–1995); the three diamonds plus the Pentastar.
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What years are 1G and 2G DSM? 1G: 1990–1994. 2G: 1995–1999.
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What's the difference between a 6-bolt and 7-bolt 4G63? Flywheel-to-crank bolt count; changeover around April 1992.
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Is crank walk a dealbreaker on a 2G? No, but check thrust play before buying.
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How much power did a stock DSM make? 1G turbo: 195 hp / 203 lb-ft (manual). 2G turbo: 210 hp / 214 lb-ft (manual).
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