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2025 Funny Car season stats
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2025 Pro Stock season stats
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2025 Pro Stock Motorcycle season stats
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Brittany Force faces her final race (at least for now) in Pomona
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Dallas Glenn returns to NHRA Finals looking for Pro Stock redemption
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A salute to John Force, NHRA's GOAT
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Austin Prock and Matt Hagan will battle for Funny Car title in Pomona
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Top Fuel champ-to-be Doug Kalitta in celebratory mood ahead of finale
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Behind the Scenes with the winners of the Dodge NHRA Nevada Nationals
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2025 Dodge NHRA Nevada Nationals Weekend Rewind
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Five things we learned in Las Vegas
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Brittany Force eying the bittersweet finish line of her driving career with pride
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Nearly three decades after his debut, Pro Stock is still fun for Jeg Coughlin Jr.
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Reigning world champ Gaige Herrera heads to Las Vegas with a sense of urgency
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Beckman looks for first Las Vegas win in nearly 20 years in loaded Vegas field
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Shawn Langdon ready to be aggressive to stay in title hunt in Las Vegas
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Justin Ashley, Mike Stavrinos discuss championship strategy heading to Vegas
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NHRA Silly Season 2025 is off to an early and wild start, with more to come
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Behind the Scenes with the winners of the 2025 Texas NHRA FallNationals
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Weekend Rewind: 2025 Texas NHRA FallNationals
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Five things we learned in Dallas
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More Top Fuel history awaits Tony Schumacher with 900th round win ahead
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Pro Stock’s Greg Anderson eyes more success at Texas NHRA FallNationals
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Texas NHRA FallNationals brings out the best in Funny Car’s Matt Hagan
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'Scrappers Sisters' ready to turn up the heat at Texas Motorplex
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Leah Pruett: “I’m looking forward to racing with and against Tony" in 2026
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Behind the Scenes with the winners of the NAPA Auto Parts NHRA Midwest Nationals
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Weekend Rewind: 2025 NAPA Auto Parts NHRA Midwest Nationals
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Five Things We Learned in St. Louis
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Mark Pawuk wins second consecutive Flexjet Factory Stock Showdown title
Inside a Pro Stock Motorcycle engine
Senior editor Kevin McKenna takes you inside a Pro Stock Motorcycle engine with this technical breakdown.
Competitors in Pro Stock Motorcycle have a choice of two drastically different powerplants, both of which are capable of 6.7-second performances at speeds approaching 200 mph. Here is a detailed look at both the Suzuki inline four-cylinder engine and the 45-degree pushrod V-Twin that powers the Harley-Davidson, Buell, and EBR entries.
| PRO STOCK MOTORCYCLE – V TWIN | PRO STOCK MOTORCYCLE – SUZUKI |
|---|---|
| (left side of header image) | (right side of header image) |
| ENGINE BLOCK | ENGINE BLOCK |
| Design: Naturally aspirated 160-cid V-Twin, two-valves per cylinder | Design: Naturally-aspirated 1,850cc (113 cid) inline four cylinder, two-valves per cylinder based on an OE Suzuki GS 1150 |
| Engine block: Billet 7075 aluminum, CNC machined | Cylinder sleeves: Ductile iron |
| Bore: 5.125 inch (typical) | Bore: 89.5mm (3.52 inch) |
| Stroke: 3.875 inch (typical) | Stroke: 73.4mm (2.89 inch) |
| Maximum bore offset: 1.0 inches | Bore centers: 95mm 1, 2 - 3, 4 (3.74inch)/120mm 2, 3 (4.72 inch) |
| Compression ratio: 14.5:1 | Compression ratio: 16:1 |
| Bank angle: 60 degree | |
| CRANKSHAFT | CRANKSHAFT |
| Crankshaft: CNC-machined steel plain-rod bearings, roller mains | Crankshaft: CNC-machined steel nine-piece pressed/welded together with roller bearing rods and mains |
| Rods: aluminum | Rods: high-strength steel |
| Oiling system: Wet or dry sump permitted | Oiling system: wet sump |
| Cylinder sleeves: Ductile iron | |
| CYLINDER HEADS | CYLINDER HEAD |
| Cylinder heads: 6013 Billet-aluminum, CNC ported | Cylinder heads: Cast aluminum, CNC ported |
| Intake valve size: 2.70 inches | Intake valve size: 46-48mm (1.81 inch-1.89 inch) |
| Exhaust valve size: 2.00 inches | Exhaust valve size: 38-40mm (1.49 inch-1.58 inch) |
| Valve covers: billet magnesium | Valve covers: billet aluminum or cast magnesium |
| Camshaft: Roller camshaft made from tool steel, four individual cams, gear driven | Camshaft: Roller chain driven, plain bearing, tool steel |
| Typical lift: 0.575-0.625 inch (x rocker ratio) | Typical lift: 16mm-18mm (.63 inch-.70 inch) |
| Rocker arm ratio: 1.8 to 2.0 | Lobe separation: 114-116 degrees |
| Lobe separation: 110-116 degrees | Duration: 265-275 degrees (intake); 265-275 degrees (exhaust) |
| Duration: 285-290 degrees (intake); 300-305 degrees (exhaust) | Lifter tappet: steel, DLC coated |
| Pushrods: 8-inch length, minimum per valve | Valve springs: Steel, 195 pounds installed, 475 pounds max lift |
| Valve springs: Steel, 500-pounds installed, 1,400-pounds, max lift | |
| INTAKE AND IGNITION | INDUCTION and IGNITON |
| Throttle body: Individual per cylinder/ billet aluminum with 3.25-inch blade | Throttle body: Individual per cylinder sealed to a common plenum airbox; Lectron carburetors also an option and widely used |
| Intake runners: Billet magnesium or billet-aluminum, common plenum, breathing from sealed airbox | Fuel Injectors: Limited to one per cylinder |
| Fuel Injectors: Limited to one per cylinder | Ignition system: electronic fuel injection/ignition, two spark plugs per cylinder. |
| Ignition system: Electronic fuel injection/two spark plugs per cylinder | Spark plugs: Denso Iridium |
| OTHER SPECS | OTHER SPECS |
| Fuel: Sunoco SR-18, 118-octane leaded (mandatory) | Fuel: Sunoco SR-18 118-octane leaded race gas (mandatory) |
| Fuel burned per run: 20-ounces, burnout to completion | Fuel burned per run: 20-ounces, burnout to run completion |
| Spark plugs: Denso Iridium | Headers: Stepped from 1.875 inch outside diameter to 2.25 inch four-into-one collector |
| Headers: stepped from 2.25 inch outside diameter to 3 inch | Engine scavenge: 20-22 inHG |
| Engine scavenge: 20-22 inHG | Engine redline: 14,000 |
| Engine redline: 10,400 rpm | Estimated horsepower and torque: 370 @13,600 rpm / 160 @ 10,000 rpm |
| Estimated horsepower and torque: 400 @ 9800/240 @ 7,000 | Estimated weight: 185-pounds dry weight (engine and transmission as singular unit) |
| Estimated weight: 220-pounds (dry weight) |