Maserati invented the production twin-turbo car in 1981 with the Biturbo's tiny IHI units, and forty years later the trident still lives on boost: Ferrari-built F160 3.0 V6 twins in the Ghibli, Quattroporte and Levante, and the F154-family V8s above them. Boost Lab, Inc. rebuilds the whole lineage: Biturbo-era IHI RHB51 and RHB52 units, the modern IHI twins under Maserati 837668 and 297712, and the Trofeo-class V8 hardware. Nationwide ship-in service.
From the first twin-turbo production car ever built to the modern Ferrari-engined lineup: forty years of boosted tridents.
The Biturbo was the world's first twin-turbocharged production car, tiny IHI RHB5-family units on the 2.0, 2.5 and 2.8 SOHC V6s across the Biturbo, 222, 228, 430, Spyder and Karif. Maserati support evaporated decades ago, but the RHB51/RHB52 architecture is the same family we service across Subarus, Yanmars and Kubotas, and rebuild parts remain in production. Early carbureted cars run their twins especially hot.
The Ghibli II's 2.0 and 2.8 twin-turbo V6s, up to 330 hp from two liters in Ghibli Cup trim, and the Shamal's 3.2 twin-turbo V8 close out the classic Biturbo era with more boost and more heat. Surviving cores show every year of it, and nearly all rebuild.
The Ferrari-built F160 twin-turbo V6, 330 to 430 hp across base, S and SQ4 trims, runs IHI twins serviced under Maserati 837668 (right) and 297712 (left). Dealer assemblies run thousands per side; the IHI cartridges underneath rebuild for a fraction of it. Left and right differ: label them when shipping.
The Ferrari F154-family 3.8 twin-turbo V8 in the GTS and Trofeo models shares its architecture with the Ferrari 488 hardware we already service. Same bench, same discipline: rebuilt as matched pairs, balanced, documented.
The MC20's 3.0 Nettuno V6 runs twin turbos with Maserati's F1-derived pre-chamber combustion pushing 621 hp. Early cores are only beginning to age out of warranty; the turbo hardware follows the same modern twin conventions and we are ready for them.
Biturbo-era values were low for decades, so the cars that survived belong to devoted owners with no dealer network, thin specialist coverage, and twins that fail together. The turbo hardware is the most fixable thing on the car: proven IHI architecture, full parts support, and a bench that treats a 1985 Biturbo with the same care as a Levante Trofeo.
From the 1981 Biturbo to a 2024 Levante, Maserati twins share oil supply, heat environment and years. When one fails, its partner has lived the same life and often ingests the failure's debris through shared plumbing. On Biturbo-era cars especially, where the labor and the plumbing are fiddly and the cars deserve to run right, rebuild the pair once instead of chasing one side twice. We assess both and tell you honestly what the second unit actually needs.
Verified IHI designations and Maserati OEM numbers. Classic-era units identify by tag; modern units by Maserati part number and side. Search by any number.
| Turbo PN | Model | OEM PN | Application | Notes |
|---|---|---|---|---|
| Tag-specific (VC35 class) | IHI RHB52 | Maserati channel, discontinued | Biturbo 2.5 (VM1R) twins | Same VC35 spec crossed the Callaway Alfa program |
| Tag-specific | IHI RHB51 | Maserati channel, discontinued | Biturbo 2.0 and early cars | Smaller RHB5-family twin |
| Tag-specific | IHI RHB52 (water-cooled revisions) | Maserati channel, discontinued | 222, 228, 430, Spyder, Karif 2.8 | Later cars gained water-cooled centers |
| Repair kit | RHB51 / RHB52 service kit | n/a | All Biturbo-era twins | Bearing and seal kits remain in production |
| Tag-specific | IHI twins (larger frame) | Maserati channel, discontinued | Ghibli II 2.0/2.8, Ghibli Cup, Shamal 3.2 V8 | Highest-strung classic-era units |
| 837668 | IHI twin, right side | Maserati 837668 | 2013+ Ghibli, Quattroporte, Levante 3.0 V6 (F160) | RH unit across base, S and SQ4 trims |
| 297712 | IHI twin, left side | Maserati 297712 | 2013+ Ghibli, Quattroporte 3.0 V6 (F160) | LH unit; sides are not interchangeable |
| Tag-specific | F154-family V8 twins | Maserati channel by VIN | Quattroporte GTS, Levante Trofeo / GTS 3.8 V8 | Ferrari 488-adjacent architecture |
| Tag-specific | Nettuno twins | Maserati channel by VIN | MC20, Grecale Trofeo 3.0 V6 | Pre-chamber era; aging into rebuild range now |
Two eras, one theme: small twins working hard in hot, tight packaging.
Early Biturbo twins, especially pre-water-cooling, coked their centers on 1980s oil and hot Italian shutdowns. Forty years later the same carbon is still in there grinding what is left of the bearings. We clean passages to bare metal and modern synthetic keeps the rebuilt pair alive.
Most surviving Biturbos, Ghiblis and Shamals sit for years between owners with the courage to run them. Storage-hardened seals smoke on revival, and the cores underneath are usually rebuildable. A reseal with modern materials is often the whole story.
Ghibli Cup and Shamal units made huge specific output for their era, and their turbine ends show it: heat-checked housings and tired wheels. Light checking is serviceable; we source within the IHI family when housings are beyond it.
Ghibli and Levante twins live hard commuter lives, and by 80,000 to 120,000 miles journal wear shows as whine, oil consumption and lazy boost. The IHI cartridges rebuild routinely at a fraction of two dealer assemblies.
Stretched oil intervals on modern Maseratis clog feed lines and banjo screens, starving twins that were otherwise healthy. Feed line service goes with every modern rebuild, and fresh oil habits protect the pair.
Shared plumbing means a failing unit feeds debris and oil to its partner, classic-era and modern alike. We rebuild as matched pairs, balance both assemblies, and report the second unit's true condition instead of guessing.
Yes. The 1981 Biturbo beat everything else to twin turbocharging in series production, using two small IHI units so each bank got its own turbo. Every modern twin-turbo V6 and V8 follows the layout Maserati proved first.
Yes. The RHB51 and RHB52 are IHI RHB5-family units, the same architecture we rebuild across Subaru, Yanmar and Kubota applications, and bearing, seal and wheel support remains in production. Your castings are the only scarce part.
Dealer twins for the F160 run thousands per side; rebuilding your original 837668 and 297712 units typically costs a fraction of one assembly, let alone two. Ship both, labeled left and right, and we quote from the actual core condition.
No. Maserati 837668 is the right-hand unit and 297712 the left, with side-specific configurations. Label them when shipping and they go back on the correct banks.
Yes, with collector documentation: photographed stages, preserved original hardware, and factory-spec balancing. These are low-survivor cars and their turbos get treated accordingly.
Start at repair.theboostlab.com, note the car and year, label left and right units, drain the oil and coolant passages, cap the openings, and double-box. Ship to Boost Lab, Inc., 37833 Pineapple Ave, Unit A, Dade City, FL 33523.