If you’re working on a Toyota project car or need a replacement gearbox, understanding the Y80 transmission and its differences with the S80 is crucial. This guide will break down everything you need to know about these two popular manual transmissions.
Y80 Transmission and Its Differences With S80
Knowing which transmission you have—or which one you should get—can save you time, money, and a lot of headaches. Both the Y80 and S80 are five-speed manual gearboxes found in iconic Honda vehicles from the 1990s and early 2000s. They look similar at a glance, but key differences in their design and application make them unique.
Let’s get into the details so you can make the best choice for your build or repair.
What is the Y80 Transmission?
The Y80 is a five-speed manual transmission produced by Honda. It’s known for its durability and smooth shifting character. This gearbox was primarily used in vehicles equipped with Honda’s B-series engines, particular those from the Acura Integra lineup.
You’ll most commonly find the Y80 transmission in these models:
* 1994-2001 Acura Integra GS-R (with the B18C1 engine)
* Some 1999-2000 Honda Civic Si (EM2 chassis with B16A2 engine)
* It’s a cable-operated transmission, meaning it uses physical cables to connect the gear shifter to the gearbox.
The Y80 is often sought after for its final drive ratio, which provides a good balance of acceleration and highway cruising. It’s a favorite among enthusiasts for both street and mild performance builds.
What is the S80 Transmission?
The S80 is also a five-speed manual transmission from Honda, sharing the same basic family lineage as the Y80. However, it was specifically paired with Honda’s B18C5 and B18C6 engines—the high-performance powerplants found in the iconic Integra Type R.
The S80 transmission is a hallmark of Honda’s performance heritage. Its design focus was on providing the quickest acceleration and most responsive feel for track-focused driving.
You’ll typically find the S80 in:
* 1997-2001 Acura Integra Type R (USDM and JDM)
* Honda Integra Type R (DC2 chassis)
* Like the Y80, it is also a cable-type transmission.
Core Differences Between the Y80 and S80 Transmissions
While they share a common ancestor, the differences between the Y80 and S80 are significant for a driver or builder. Here’s a direct comparison of their key features.
1. Final Drive Ratio
This is the most talked-about difference. The final drive determines how many times the driveshaft spins for each rotation of the wheel. A higher (numerically larger) final drive gives you quicker acceleration but lower top speed and higher engine RPMs at cruise.
* Y80 Final Drive: 4.40
* S80 Final Drive: 4.785
The S80’s much shorter final drive is its defining trait. It makes the car feel incredibly snappy and accelerates much harder out of corners, which is perfect for racing. The Y80’s 4.40 final drive is noticeably longer, offering more relaxed highway driving.
2. Gear Ratios
The individual gear ratios work together with the final drive. The S80 doesn’t just have a shorter final drive; its first through fourth gears are also generally shorter than the Y80’s.
Here’s a simplified comparison (ratios can vary slightly by model year):
* Y80 Gear Ratios: 1st: 3.230, 2nd: 1.900, 3rd: 1.360, 4th: 1.034, 5th: 0.787
* S80 Gear Ratios: 1st: 3.230, 2nd: 2.105, 3rd: 1.458, 4th: 1.107, 5th: 0.848
Notice that 1st gear is often the same, but the S80’s gears are tighter from 2nd through 5th. This keeps the engine in its optimal power band during aggressive driving.
3. Limited-Slip Differential (LSD)
This is a critical performance differentiator.
* Y80 (GS-R): Came equipped with a Helical Limited-Slip Differential. This type of LSD is smooth and great for street use, providing torque to the wheel with grip without abrupt engagement or noise.
* S80 (Type R): Came equipped with a Mechanical Clutch-Type Limited-Slip Differential. This is a more aggressive, race-oriented unit. It provides near-lockup under power, maximizing traction when exiting a corner, but can be noisy and “chatter” during low-speed turns.
4. Synchro Design and Shift Feel
The S80 transmission often featured carbon-lined synchros, which were more durable and could handle faster, more aggressive shifting. Many drivers report the S80 has a slightly more precise, “notchy” feel compared to the Y80, which is known for being smooth and forgiving. The Y80’s synchros are still robust but designed for general performance use.
5. Case and Identification
Physically, they look almost identical. The best way to identify them is by the stamped code on the bellhousing. You will clearly see either “Y80” or “S80.” Also, the Type R S80 often has a blue painted ring around the differential section, but this can wear off or be repainted.
Which Transmission is Right for You?
Choosing between a Y80 and an S80 depends entirely on your goals for the vehicle.
Choose the Y80 transmission if:
* Your car is a daily driver or weekend cruiser.
* You want lower engine RPMs for quieter, more efficient highway driving.
* You prefer a smoother, more street-friendly helical LSD.
* You are building a mild performance street car.
* You often find the S80’s shorter gearing to be to aggressive for your needs.
Choose the S80 transmission if:
* Your car is primarily for track days, autocross, or spirited canyon driving.
* Maximizing acceleration is your top priority.
* You want the aggressive lockup of a clutch-type LSD for maximum corner exit traction.
* You don’t mind higher engine noise and slightly reduced fuel economy on the highway.
* You are building a car with a Type R theme or seeking authentic performance parts.
Common Swaps and Compatibility
Both transmissions are popular swap candidates into lighter chassis like the Honda Civic (EJ, EK). Here’s what you need to know:
* Engine Compatibility: Both bolt directly to B-series engines (B16, B17, B18). You cannot bolt them directly to D-series or K-series engines without adapters.
* Mounts: They use the same transmission mount points, so a mount kit for a B-series swap will work for either gearbox.
* Axles: You must use axles that match the transmission’s differential. For a swap, this typically means using the intermediate shaft and axles from the donor car (like an Integra) or a custom-built swap set.
* Shift Linkage: Cable shift linkages from the donor vehicle (Integra) are required and will work with both.
* Clutch and Flywheel: Any clutch kit designed for a B-series engine will work with either transmission, as the spline count and size are the same.
One important note: if you put an S80 into a lighter car like a Civic, the acceleration will feel even more extreme due to the reduced weight. It can be a very fun but intense setup.
Maintenance and Common Issues
Both transmissions are robust, but they have common pain points as they age.
Shared Maintenance Items:
1. Fluid Changes: Use only genuine Honda MTF (Manual Transmission Fluid) or a high-quality synthetic alternative. Change it every 30,000 miles for severe use.
2. Shift Cables: The plastic ends on the shift cables can wear out, causing sloppy or imprecise shifting. Replacement cables or end bushings are a common fix.
3. Clutch Hydraulics: The clutch master and slave cylinders are known failure points. If you have a soft pedal or difficulty shifting, check these first.
Y80-Specific Considerations:
* The helical LSD can wear, but it’s generally long-lasting. Fluid changes are key.
* 2nd and 3rd gear synchros can wear with aggressive driving, leading to grinding.
S80-Specific Considerations:
* The clutch-type LSD requires specific friction modifier additive in the transmission fluid. Without it, you will get severe chatter during low-speed turns.
* The clutch pack inside the LSD can wear out and require rebuilding for proper function.
* The aggressive use these boxes often see means synchro wear is more common, so checking gear oil condition is even more critical.
FAQ Section
Can I put an S80 transmission on a GS-R engine (B18C1)?
Yes, absolutely. It bolts right on. This is a very popular upgrade for GS-R owners who want the shorter, more aggressive gearing of the Type R. You’ll need the S80 transmission, its corresponding shift linkage, and the correct axles.
Is the Y80 or S80 stronger?
Internally, they are very similar in strength. The gearsets and cases are equally durable for most applications. The perceived “strength” of the S80 often comes from its more aggressive LSD and synchros designed for harder use, not necessarily thicker gears.
What fluid should I use in my S80 transmission?
You must use Honda MTF or a compatible fluid that is approved for use with a clutch-type limited-slip differential. Always add the Honda LSD friction modifier additive to prevent chatter. Not adding it is a common mistake people make.
Will a Y80 transmission fit in my Civic?
It will, but not directly. You need a complete B-series engine swap mount kit. The Y80 transmission will then attach to your swapped B-series engine. Remember, you also need the correct axles and shift linkage from a B-series donor car like an Integra.
How can I tell if I have a real S80 transmission?
Look for the “S80” stamp on the bellhousing. Also, check for the presence of a clutch-type LSD (you can feel it by turning one wheel; the opposite wheel should want to turn the same direction). The blue paint on the differential case is a clue, but not a guarantee, as it can be faked.
What is the price difference between Y80 and S80?
The S80 transmission is typically much more expensive due to its rarity and high demand from enthusiasts. A used Y80 might be found for a reasonable price, while a verified, good-condition S80 often commands a premium, sometimes two to three times the price.
Choosing between these two transmissions comes down to your driving style and goals. The Y80 offers a fantastic, balanced experience for the street. The S80 is a purpose-built tool for going fast. By understanding their differences—from the final drive to the type of limited-slip differential—you can select the gearbox that will make your project car perform exactly how you want it to. Always remember to check the transmission code stamp before you buy to ensure your getting the model you expect.