Moroso Says Mechanical Water Pumps Can Consume 15–20 HP
One of the headline claims for the Moroso 63750 is its potential reduction in parasitic horsepower loss.
Moroso states that dynamometer testing has demonstrated that many mechanical water pumps create substantial drag at high RPM, potentially absorbing 15–20 horsepower.
That doesn’t mean installing the 63750 automatically adds exactly 20 horsepower to every engine.
The actual difference depends on factors including:
- Engine speed
- Mechanical water-pump design
- Pulley ratio
- Coolant-system restriction
- Pump condition
- Existing accessory drive
- Electric-system load
The real principle is straightforward.
A mechanical water pump requires horsepower to turn.
Removing that pump from the engine’s conventional accessory drive reduces the direct mechanical load on the crankshaft.
For a drag car where relatively small horsepower improvements matter, that can be worthwhile.
Designed Specifically for Drag Racing
Moroso explicitly states that the 63750 is intended for drag-race applications only.
That’s a critical distinction for the product page.
This isn’t a universal street-car cooling upgrade simply because Moroso describes the engine fitment as universal.
Drag racing creates a very different cooling-system duty cycle than street driving.
A drag car may:
- Warm up in the pits.
- Stage.
- Make a relatively short full-throttle pass.
- Return to the pits.
- Use electric cooling equipment between rounds.
A street car may need continuous cooling for hours while sitting in traffic, cruising on the highway and operating accessories.
Those are very different requirements.
Broad American V8 and V6 Compatibility
One of the strongest features of the Moroso 63750 is its broad engine compatibility.
Moroso lists applications including:
- Small Block Chevy
- Big Block Chevy
- Chevrolet 90-degree V6
- Short-style Chevy water pumps
- Long-style Chevy water pumps
- Ford 351W
- Ford 351C
- Ford big-block engines
- Chrysler small-block engines
- Chrysler big-block engines
Moroso’s installation documentation provides specific mounting-hole locations and hardware arrangements for the different engine families.
That makes the kit universal by engine application, rather than vehicle-specific.
The water pump and engine configuration matter more than the VIN.
Small Block Chevy Compatibility
The 63750 is a particularly natural fit for traditional Small Block Chevy drag-racing combinations.
Moroso’s installation instructions provide a dedicated SBC mounting configuration, and the company also supports the system with alternator mounting and drive components designed around Small Block Chevy installations.
Both long- and short-style Chevrolet water-pump configurations are supported according to Moroso’s application information.
That makes the kit useful across a wide range of SBC combinations where a conventional mechanical pump is retained.
Big Block Chevy Compatibility
Big Block Chevy racers are also directly supported.
Moroso’s installation diagram includes a dedicated Big Block Chevy mounting location, and the company offers BBC alternator mounting hardware designed specifically around engines using the 63750.
That makes the kit relevant to:
- 396 BBC
- 402 BBC
- 427 BBC
- 454 BBC
- 496 stroker
- Larger racing BBC combinations
As always, verify the actual water-pump and accessory configuration rather than assuming every modified BBC retains factory component locations.
After several decades of racing modifications, the phrase “stock accessory drive” can become fairly theoretical.
Ford Compatibility
Moroso also supports several popular Ford engine families.
The 63750 is listed for:
- Ford 351W
- Ford 351C
- Ford big-block applications
Moroso’s installation documentation shows specific mounting locations for Windsor and Cleveland engines as well as big-block Ford configurations.
This broadens the kit well beyond the traditional Chevy drag-racing market.
Chrysler Small- and Big-Block Compatibility
Mopar racers aren’t left out either.
Moroso lists both:
- Chrysler small-block
- Chrysler big-block
applications for the 63750.
Again, the mounting arrangement changes according to the engine family, which is why Moroso’s supplied hardware and application-specific mounting instructions matter.
Complete 12-Volt Drive System
The Moroso 63750 includes the primary components needed to electrically drive the mechanical water pump.
The kit includes:
- 12-volt electric motor
- Electric-motor mounting plate
- Water-pump drive pulley
- Electric-motor pulley
- Drive belt
- Required mounting hardware
- Toggle switch
Moroso identifies the replacement motor as Part No. 97210.
That means the motor, pulleys and belt are individually serviceable rather than turning the entire kit into scrap if one wear component eventually needs replacement.
Approximately 2,600 RPM Motor Speed
Moroso’s installation instructions state that the electric motor operates at approximately 2,600 RPM under full load.
The supplied pulley combination translates that motor speed into water-pump operation appropriate for the intended drag-racing use.
Moroso also offers an optional pulley for racers who need increased water-pump speed.
Optional 97252 Pulley Increases Pump Speed
Moroso offers the 97252 14-tooth water-pump pulley as an optional upgrade.
According to Moroso, the 97252 increases water-pump speed by approximately 28 percent.
That gives racers another tuning option when the standard pulley ratio isn’t providing the desired coolant circulation.
Increasing pump speed should still be treated as part of the overall cooling-system setup rather than an automatic solution to overheating.
Cooling performance also depends on:
- Radiator capacity
- Coolant airflow
- Fan performance
- Thermostat or restrictor configuration
- Coolant passages
- System pressure
- Air trapped in the cooling system
- Engine heat output
The pump is only one part of the equation.
Compatible With Moroso 63760 Thermostatic Switch
Moroso recommends its 63760 Thermostatic Water Pump Switch as an available companion to the 63750.
A thermostatic switch allows the electric drive system to be controlled according to coolant temperature rather than relying exclusively on manual operation.
That can make cooling-system management more consistent between drag-racing rounds.
It also reduces the possibility of the driver becoming distracted and forgetting to switch the pump on.
Humans are remarkably sophisticated.
We also routinely forget to turn things on.
Manual Toggle Switch Is Included
The standard 63750 includes a toggle switch for manual water-pump operation.
Moroso’s installation instructions specify connecting the electric motor through the supplied switch to a fused 12-volt power source.
That provides straightforward control over pump operation.
For a purpose-built drag car, manual control can be useful because the racer may want to operate the water pump independently of the engine.
Run the Water Pump With the Engine Off
One of the major practical advantages of an electrically driven water pump is the ability to circulate coolant when the engine isn’t running.
Between drag-racing rounds, the engine can be shut down while the water pump continues circulating coolant.
When paired with an electric radiator fan, this can help pull heat out of the engine without leaving it idling.
That matters because idling the engine to cool it also continues generating combustion heat.
With electric pump and fan control, the cooling system can continue doing its job while the engine itself takes a break.
Useful Between Drag-Racing Rounds
Consistency is extremely important in bracket racing and other competitive drag-racing formats.
Engine temperature can influence:
- Intake-air temperature
- Fuel behavior
- Ignition requirements
- Engine clearances
- Power output
- ET consistency
Being able to manage coolant circulation between rounds can help the racer return the engine to a more predictable starting temperature before the next pass.
The 63750 therefore offers benefits beyond simply reducing mechanical drag at full throttle.
Proper Cooling-System Diagnosis Still Matters
An electric drive isn’t a cure for a cooling system that already has mechanical problems.
Before modifying pump drive, make sure the cooling system is healthy.
Check:
- Radiator condition
- Coolant level
- System pressure
- Fan operation
- Thermostat or restrictor
- Water-pump condition
- Air pockets
- Head-gasket condition
- Hose integrity
My Pro Street’s cooling-system technical coverage is designed around exactly these fundamentals: diagnose the system before replacing parts randomly.
An engine that overheats because the radiator is plugged won’t suddenly become happy because the water pump has its own electric motor.
Proper Belt Tension Is Important
Moroso’s installation procedure specifies approximately 1 to 2 inches of slack in the electric water-pump drive belt.
This is not intended to be tensioned like a conventional serpentine accessory belt.
Correct belt adjustment helps the system operate without excessive load on the electric motor or water-pump bearings.
Follow Moroso’s installation procedure rather than tightening the belt until it resembles a guitar string.
Some Water Pumps May Require Minor Fitment Work
Moroso’s installation instructions note that mechanical water-pump construction can vary.
On some pumps, the water-pump shaft diameter may require the center opening in the supplied pulley to be enlarged.
Certain pump castings may also have reinforcing ribs near the pump snout that interfere with pulley clearance.
Moroso instructs installers to carefully modify those areas where necessary for proper pulley fitment.
That is another reason this should be marketed as a universal racing drive kit, not as a direct-fit vehicle replacement.
Some installation work may be required.
Fan Clearance Requires Attention
If the engine retains a mechanical fan, clearance between the fan and electric-drive belt becomes important.
Moroso’s instructions specify using a 1-inch fan spacer where necessary to prevent the fan blades from contacting the belt.
The belt also needs to be positioned before final fan installation because the fan blades can prevent the belt from being installed afterward.
Many purpose-built drag cars use an electric radiator fan instead, which can simplify packaging considerably.
Electrical Installation Requires a Fuse
Moroso’s instructions specify connecting the motor to a 12-volt power supply through a 10-amp fuse.
That fuse is important.
Electric motors can draw substantial current, and an unfused circuit can turn an ordinary wiring fault into a much larger problem.
The installation should use:
- Proper automotive wire
- Secure terminals
- Good ground
- Appropriate fuse protection
- Heat protection where necessary
- Proper routing away from moving components
Race-car electrical systems deserve the same attention as the mechanical components.
Works With Moroso Alternator Drive Systems
Removing the conventional accessory drive can complicate alternator placement.
Moroso anticipated that problem.
The company offers alternator mounting and drive systems designed for engines using electric water pumps or the 63750 electric-drive kit.
For example, Moroso offers dedicated systems for both Small Block Chevy and Big Block Chevy applications.
That lets racers build an accessory system around the electric water-pump drive rather than trying to retain a conventional belt arrangement that defeats part of the reason for installing it.
BBC Alternator Options
For Big Block Chevy applications, Moroso offers dedicated alternator hardware compatible with the 63750.
The company’s 63840 alternator mounting kit is designed for BBC engines using Moroso water-pump configurations including the 63750 electric drive.
Moroso also offers the 63841 BBC alternator drive kit, which is designed around its electric water-pump and electric-drive arrangements.
That creates a coordinated racing accessory system rather than a collection of improvised brackets.
SBC Alternator Options
Small Block Chevy racers receive similar support.
Moroso’s 63843 alternator drive kit is designed for SBC applications using compatible Moroso water pumps and the 63750 electric-drive system.
This becomes especially useful on cars that still need an alternator for:
- Electric fuel pumps
- Ignition systems
- Electric fans
- Data acquisition
- Water-pump drive
- Other electrical accessories
Removing mechanical accessory drag is useful.
Discovering that the battery is dead before the semifinal round is less useful.
Electric Water Pump Drive vs Complete Electric Water Pump
There are two basic approaches to electrically powered coolant circulation.
Moroso 63750 Electric Drive
The 63750:
- Retains a compatible mechanical water pump
- Adds an external 12V motor
- Uses a small belt drive
- Reduces direct crankshaft accessory load
- Provides engine-off coolant circulation
- Fits numerous American V8/V6 applications
- Is intended for drag racing
Complete Electric Water Pump
A dedicated electric water pump:
- Replaces the mechanical pump assembly
- Uses an integrated electric motor
- Can reduce accessory-drive complexity
- May provide additional engine-front clearance
- Requires engine-specific pump compatibility
Neither approach is automatically better.
The right solution depends on the engine, racing class, cooling requirements, packaging and budget.
Why Racers Still Use the 63750 Design
Modern integrated electric pumps may look more sophisticated, but the external electric-drive concept still has some practical advantages.
It allows racers to:
- Retain a proven mechanical pump
- Electrically control pump operation
- Service the motor separately
- Change pulley ratio
- Run the pump with the engine off
- Reduce crankshaft-driven accessory load
For traditional American V8 drag combinations, simplicity has value.
Especially when the simple thing has replacement parts available separately.
Replacement Components Are Available
Moroso currently lists several replacement components for the 63750:
97210 — 12-Volt Electric Motor
97220 — Water Pump Pulley
97230 — 21-Inch Electric Water Pump Belt
97250 — Electric Motor Pulley
Moroso also offers:
97252 — 14-Tooth Pulley for approximately 28% increased pump speed
63760 — Thermostatic Water Pump Switch
That parts support makes the system serviceable over the long term.
Moroso 63750 Specifications
Part Number: 63750
Product: Electric Water Pump Drive Kit
Application: Drag racing
Fitment: Universal / engine-specific mounting
Voltage: 12 volts
Motor Speed: Approximately 2,600 RPM at full load
Water Pump: Compatible mechanical pump retained
Drive Type: Electric motor with pulley and belt
Motor: Included
Water Pump Pulley: Included
Motor Pulley: Included
Drive Belt: Included
Mounting Hardware: Included
Toggle Switch: Included
Recommended Circuit Protection: 10-amp fuse
Optional Thermostatic Switch: Moroso 63760
Optional High-Speed Pulley: Moroso 97252
Claimed Mechanical Pump Drag: As much as 15–20 hp at high RPM according to Moroso dynamometer testing
Product Quantity: 1 kit
Listed Weight: Approximately 6.55 lb
Universal Fitment Needs Some Explanation
The supplied product information correctly calls the 63750 universal, but customers need more information than that.
A better ecommerce fitment description is:
Fitment Type: Universal performance/racing
Engine Compatibility: Most traditional American V8 and selected V6 engines
Supported Families: Chevy V8 and 90-degree V6, Ford 351W/351C and compatible big-block Ford, Chrysler small-block and big-block
Use: Drag racing only
Water Pump Requirement: Compatible mechanical water pump
The kit isn’t a universal electric pump that can simply be bolted onto any engine.
It is a universal electric drive system for compatible mechanical water pumps.
That distinction should be obvious before the customer orders it.
Who Should Buy the Moroso 63750?
The Moroso 63750 makes the most sense for a dedicated drag-racing vehicle using a traditional American V8 or compatible V6 and retaining a mechanical water pump.
Strong applications include:
- Small Block Chevy drag cars
- Big Block Chevy drag cars
- 351W Ford combinations
- 351C Ford builds
- Big Block Ford race engines
- Small Block Chrysler engines
- Big Block Mopar combinations
- Bracket cars
- Pro Street race builds
- Dedicated quarter-mile and eighth-mile cars
For a street-driven vehicle requiring continuous-duty cooling, choose a cooling-system solution specifically designed and rated for that use.
Final Verdict
The Moroso 63750 Electric Water Pump Drive Kit is a classic drag-racing solution to two problems: mechanical water-pump drag and the inability to circulate coolant with the engine shut off.
Moroso’s universal design supports many traditional American V8 and V6 combinations, while the complete kit includes the 12-volt motor, pulleys, belt, hardware and manual switch required to electrically drive a compatible mechanical water pump.
The potential performance benefit is easy to understand. Moroso says mechanical water pumps can absorb as much as 15–20 horsepower at high RPM, and the 63750 removes that pump from the conventional crankshaft-driven accessory system.
Just keep the application in perspective.
Moroso explicitly designed the 63750 for drag racing.
If your commute includes staging lanes, a burnout box and a timing slip, you’re in the target demographic.


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