Engine Parts - EFI Upgrade Kits

500 EFI Flame Arrestor Upgrade Kit
Starting From:
$1,699.99

This Part has options, please click the button below to order.

500 EFI Flame Arrestor Upgrade Kit

755-68 + Option(s)

500 EFI Flame Arrestor Upgrade Kit

Hardin Marine has taken your factory Mercury Racing EFI throttle body and combined their precision machining and tuning experience into a power producing option for all Mercury 500/525 EFI applications. High flow throttle bodies wake these engines up. Boasting more than 60% more air inlet surface area, these units will now support air flow needs of up to 900 horsepower. So whether you want to own the hottest looking flame arrestor for appearance reasons or performance reasons, Hardin marine has it.

Hardin Marine will also recalibrate your Mercury ECU (computer) to yield the very most of your engines power The ECU precisely controls fuel requirements, detonation control, idle speed and RPM limitations We have dyno-tested multiple combinations and know what works!

Components Include:
  • HP 500 Flame Arrestor
  • 500 EFI Tuned & Bored Throttle Body 1000CFM
  • Computer Re-Calibration & Monitoring (ECU) - Non Supercharged Engine
  • HP 500 / 525 Flow Command Fuel Pressure Regulator


Computer Re-Calibration & Monitoring (ECU) - Non Supercharged Engine
Your Price:
$375.00

Computer Re-Calibration & Monitoring (ECU) - Non Supercharged Engine

620-75302

Computer Re-Calibration & Monitoring (ECU) - Non Supercharged Engines

Have you modified your stock Mercury EFI engine by adding high performance exhaust, a bigger cam, a high flow flame arrestor, or added a supercharger?

Hardin Marine can recalibrate your Mercury ECU (computer) to yield the very most of your engines power The ECU precisely controls fuel requirements, detonation control, idle speed and RPM limitations We have dyno-tested multiple combinations and know what works! Call us with your application requirements and we will lead you to maximum horsepower from you EFI engine Allow approximately 4-7 days turn around time.


Computer Re-Calibration & Monitoring (ECU) - Supercharged Engines
Your Price:
$425.00

Computer Re-Calibration & Monitoring (ECU) - Supercharged Engines

620-75303

Computer Re-Calibration & Monitoring (ECU) - Supercharged Engines

Have you modified your stock Mercury EFI engine by adding high performance exhaust, a bigger cam, a high flow flame arrestor, or added a supercharger?

Hardin Marine can recalibrate your Mercury ECU (computer) to yield the very most of your engines power The ECU precisely controls fuel requirements, detonation control, idle speed and RPM limitations We have dyno-tested multiple combinations and know what works! Call us with your application requirements and we will lead you to maximum horsepower from you EFI engine Allow approximately 4-7 days turn around time.


Computer Re-Calibration & Monitoring (ECU) - Non Supercharged Engine
Your Price:
$950.00

ECM 555 Computer Re-Calibration & Monitoring (ECU) - Non Supercharged Engine

620-75309

ECM 555 Computer Re-Calibration & Monitoring (ECU) - Non Supercharged Engines

Have you modified your stock Mercury EFI engine by adding high performance exhaust, a bigger cam, a high flow flame arrestor, oradded a supercharger?

Hardin Marine can recalibrate your Mercury ECU (computer) to yield the very most of your engines power The ECU precisely controls fuel requirements, detonation control, idle speed and RPM limitations We have dyno-tested multiple combinations and know what works! Call us with your application requirements and we will lead you to maximum horsepower from you EFI engine. Allow approximately 4-7 days turn around time.


500 EFI Tuned & Bored Throttle Body 1000CFM
Your Price:
$629.99

500 EFI Tuned & Bored Throttle Body 1000CFM

620-15530

500 EFI Tuned & Bored Throttle Body 1000CFM

Hardin Marine has taken your factory Mercury Racing EFI throttle body and combined their precision machining and tuning experience into a power producing option for all Mercury 500/525 EFI applications. High flow throttle bodies wake these engines up.

These “Monoblade” flow 1000 CFM to match Mercury’s 525HP EFI engine. The “Monoblade” has self lubricating bronze bushings for the shaft to rotate on, knife edged stainless steel throttle blade, Stock OEM sensors and throttle cable mounts in the original location. 25 HP gain is available with recalibration of the ecu and the throttle valve. Port matching to the plenum chamber and the center divider is required to be removed from the inlet of manifold allowing room for the throttle body blade to move freely.

Now that the units match the 525 efi size. This takes a 525 gasket where it mates to the manifold not the original o-ring that the 500s had. One bolt hole needs to be clearance d slightly once the gasket is laid on the throttle body. The front is machined and drilled/tapped 5/16 fine thread and now accepts the 525 flame arrestor.

Optional High Flow flame arrestor is suggested #625-5250

Note: You will have to remove and send in your throttle body to have this process done. This is not a shelf item. Please call our technical staff for any questions or assistance on the process.

Sold as an Exchange, $500.00 Core Charge.

HP525 Bored Throttle Body 1300CFM
Your Price:
$629.99

HP525 Bored Throttle Body 1300CFM

620-15535

HP525 Bored Throttle Body 1300CFM 

Hardin Marine has taken your factory Mercury Racing EFI throttle body and combined their precision machining and tuning experience into a power producing option for all Mercury 500/525 EFI applications.

These throttle Bodies reinstall easily providing an OEM fit while offering improved performance and quality than the stock OEM units. A factory stock 1080CFM unit is CNC Machined, Ported, and finally flowed to 1308CFM. A new larger precision knife blade style throttle blade is then hand contoured and (Blue Printed) to the throttle body bore. This delivers Increased airflow, improved throttle response, as well as 10-15 additional horsepower. These units are sold on an exchange basis. Note an aftermarket flame arresstor is suggested (Part #625-5250)  due to the increased throttle bore opening size 

Note: You will have to remove and send in your throttle body to have this process done. This is not a shelf item. Please call our technical staff for any questions or assistance on the process.

Max Volt Catalyst Eliminator Computer
Starting From:
$459.99

This Part has options, please click the button below to order.

Max Volt Catalyst Eliminator Computer

121-120 + Option(s)

Max Volt Catalyst Eliminator Computer

If increased engine performance is what you are after but have concerns about the catalyst equipment on your engine, then the Catalytic Eliminator Computer (CEC) is what you need! Designed specifically for marine engines, Maxvolt Performance worked with a team of marine electrical engineers to create a product this simple and gets the job done. There is no cutting or splicing of wires; everything is plug and play! And there are three ways to play! Your engine can be Aggressive,Mild, or Basic:

Aggressive: If you want to be aggressive and replace your stock exhaust system with a header system, then this is the product for you. We worked with the header design teams at Hardin Marine and other popular manufacturers to be sure their headers are manufactured to work with CEC. To be compatible, the header must be made to accept a pre-oxygen sensor!

Mild:If changing over to headers is too aggressive for you, then removing the catalysts but retaining the stock exhaust manifolds is the path for you. Depending on the engine, 10 to 15 horsepower will be gained by removing the catalysts and using the factory exhaust system.

Basic:If your boat has fouled its post oxygen sensors and is no longer under the factory warranty, then you know what it costs to have new sensors installed and the trouble codes cleared. For less than what your dealer charged, you can purchase and install the CEC and never have to worry about throwing that fault code again!

WARNING! This module is not to be used on emissions regulated waterways. The intent of this module is to allow the running of a catalyzed marine engine without the catalytic converters installed and without triggering any ECU error codes. With the engine operating in this condition, the emissions control system will be rendered inoperative. For this reason, do not operate the vessel on emissions regulated waterways. This computer system is not legal for any purpose other than testing purposes and not for use on any state or federal waterway.

SE Special Edition Tuning Kit For MerCruiser 454 & 502 Magnum MPI Engines
Your Price:
$249.99

SE Special Edition Tuning Kit For MerCruiser 454 & 502 Magnum MPI Engines

620-75304

"SE" Special Edition Tuning Kit For MerCruiser 454 & 502 Magnum MPI Engines

This kit is an excellent choice for those just beginning performance modifications on a MerCruiser Magnum EFI Series engine. This kit includes the "SE" Special Edition flame arrestor that utilizes a high flow K&N clamp-on style filter element and high velocity air inlet adapter which increases air flow by as much as 20%. The included Flow Command adjustable fuel pressure regulator allows you to tune to the proper air flow by allowing adjustments from 25 to 65 PSI.


SS Sport Series Tuning Kit For MerCruiser 454 & 502 Magnum MPI Engines
Your Price:
$599.99

SS Sport Series Tuning Kit For MerCruiser 454 & 502 Magnum MPI Engines

620-75305

"SS" Sport Series Tuning Kit For MerCruiser 454 & 502 Magnum MPI Engines

Do you want quicker acceleration, faster planing, and increased performance of up to 15 HP? If so, the "SS" Super Sport tuning kit for your MerCruiser Magnum MPI engine is what you need. This kit includes the "SS" Sport Series flame arrestor that utilizes a clamp-on style K&N element with our high velocity style air inlet. This kit include re-programming of your factory ECU in which we will modify both the fuel and spark curves as well as increasing your rev limiter and injector timing to 5400 RPM. This kit also comes with an adjustable billet Flow Command fuel pressure regulator that allows you to tune your air fuel mixture for optimum performance.

NOTE: You will need to send us your ECU with this questionnaire for re-calibration.


Stage 1 Upgrade for Mercury 525 EFI
Your Price:
$1,499.99

Stage 1 Upgrade for Mercury 525 EFI

755-6830

Stage 1 Upgrade for Mercury 525 EFI

Performance computer re-calibration and a Custom High flow Billet Flame Arrestor that increases the maximum power by more than 25 HP* and 30 pounds of torque*. This upgrade will not only improve overall top end power but it also increases the low end power for a decrease in on to plane time and a gain in acceleration you can feel. The Preset Mercury racing factory rpm limit is also increased from 5400 to 6000 this is the point the the factory power band peaks.


Stage 2 Upgrade for Mercury 525 EFI
Your Price:
$2,099.99

Stage 2 Upgrade for Mercury 525 EFI

755-6835

Stage 2 Upgrade for Mercury 525 EFI

Performance computer recalibration and a Custom High flow Billet Flame Arrestor, and Modified 1300CFM Throttle body(exchange) that increases the maximum power by more than 35HP* and 38 pounds of torque*. This upgrade will not only improve overall top end power but it also increases the low end power for a decrease in on to plane time and a gain in acceleration you can feel. The Preset Mercury racing factory rpm limit is also increased from 5400 to 6000 this is the point the the factory power band peaks. Part # 755-6835

Stage 1 Upgrade for Mercury 525 EFI
Your Price:
$6,499.99

Stage 3 Upgrade for Mercury 525 EFI

755-6840

Stage 3 Upgrade for Mercury 525 EFI

Performance computer recalibration, Custom High flow Billet Flame Arrestor, Modified 1300CFM Throttle body(exchange). Dart Pro1 Marine Cylinder head kit complete assembled with valves and springs, pushrods, ARP Cyl Head mounting hardware, Head, Intake, and Exhaust Gaskets. This kit has shown proven increases taking the maximum power out put up by more than 75-85HP* and 80 pounds of torque*. This upgrade is for the person seeking maximum power out put from their naturally aspirated Mercury racing 525 engine package. This kit offers a broad increase in power across the entire rpm power band. The Preset Mercury racing factory rpm limit is increased from 5400 to 6000 to take full advantage of the new components increased air flow capabilities. Part # 755-6840

Kit Performance features:
 
• 6000 RPM limit vs. stock 5400 RPM limit giving increased effectiveness of peak power band.
• Hi-performance PCM calibration
• Increased horsepower for increased top speed
• Increased low-speed torque for improved out of the hole launch
• Increased low, mid and high speed torque for better acc. & throttle response
• Increased spark at low and mid speeds for increased engine efficiency
• 91 octane safe (RON+MON)/2
• Stock idle, starting and drive-ability is maintained




496 HO Stage 1
Your Price:
$660.99

496 HO Stage 1

485CM-496HO

496 HO Stage 1

With full PCM control, we can offer customers many different options for stock and modified engines. Whether its the Stage 1 and 2 packages or custom calibrations for your application, we can easily handle it with incredible accuracy and a ultra fast turn-around time.

The Stage 1 system is a computer re-calibration that increases the maximum rpm level while maintaining a conservative timing curve for 89-octane gas. This calibration is designed to be conservative and reliable like stock, but a higher maximum rpm level for more prop selection. Stage 1 achieves only modest power increases such as 8-10 foot-pounds of torque and 8-10 horsepower.

    Key features:
  • 5450 RPM limit (5250 on Base models)
  • 89 octane safe

NOTE: You will have to remove and send in your ECU to have this process done.


496 HO Stage 1 (DTS)
Your Price:
$660.99

496 HO Stage 1 (DTS)

485CM-496HOD

496 HO Stage 1 (DTS)

 

With full PCM control, we can offer customers many different options for stock and modified engines. Whether its the Stage 1 and 2 packages or custom calibrations for your application, we can easily handle it with incredible accuracy and a ultra fast turn-around time.

The Stage 1 system is a computer re-calibration that increases the maximum rpm level while maintaining a conservative timing curve for 89-octane gas. This calibration is designed to be conservative and reliable like stock, but a higher maximum rpm level for more prop selection. Stage 1 achieves only modest power increases such as 8-10 foot-pounds of torque and 8-10 horsepower.

    Key features:
  • 5450 RPM limit (5250 on Base models)
  • 89 octane safe

NOTE: You will have to remove and send in your ECU to have this process done.


496 Mag Stage 1
Your Price:
$660.99

496 Mag Stage 1

485CM-496MAG

496 Mag Stage 1

 

With full PCM control, we can offer customers many different options for stock and modified engines. Whether its the Stage 1 and 2 packages or custom calibrations for your application, we can easily handle it with incredible accuracy and a ultra fast turn-around time.

The Stage 1 system is a computer re-calibration that increases the maximum rpm level while maintaining a conservative timing curve for 89-octane gas. This calibration is designed to be conservative and reliable like stock, but a higher maximum rpm level for more prop selection. Stage 1 achieves only modest power increases such as 8-10 foot-pounds of torque and 8-10 horsepower.

    Key features:
  • 5450 RPM limit (5250 on Base models)
  • 89 octane safe

NOTE: You will have to remove and send in your ECU to have this process done.


496 Mag Stage 1 (DTS)
Your Price:
$660.99

496 Mag Stage 1 (DTS)

485CM-496MAGD

496 Mag Stage 1 (DTS)

 

With full PCM control, we can offer customers many different options for stock and modified engines. Whether its the Stage 1 and 2 packages or custom calibrations for your application, we can easily handle it with incredible accuracy and a ultra fast turn-around time.

The Stage 1 system is a computer re-calibration that increases the maximum rpm level while maintaining a conservative timing curve for 89-octane gas. This calibration is designed to be conservative and reliable like stock, but a higher maximum rpm level for more prop selection. Stage 1 achieves only modest power increases such as 8-10 foot-pounds of torque and 8-10 horsepower.

    Key features:
  • 5450 RPM limit (5250 on Base models)
  • 89 octane safe

NOTE: You will have to remove and send in your ECU to have this process done.


496 Magnum Base Stage 2 Kit
Your Price:
$707.99

496 Magnum Base Stage 2 Kit

485MK-5350

496 Magnum Base Stage 2 Kit

With full PCM control, we can offer customers many different options for stock and modified engines. Whether its the Stage 1 and 2 packages or custom calibrations for your application, we can easily handle it with incredible accuracy and a ultra fast turn-around time.

The Stage 2 maximizes the power output of the stock engine by running 91 octane or better, increasing the maximum spark advance, increased ignition power from the individual coils, denser air charge from the low temp thermostat and maximized air-fuel ratio in each individual cylinder. Calibration increases torque levels throughout the entire rpm curve while making more peak hp for increased speeds.

    Key features:
  • Hi-performance PCM calibration
  • Low-temp thermostat
  • 5450 RPM limit
  • 5% - 8% power increase over stock
  • Increased acceleration with increased torque output

NOTE: You will have to remove and send in your ECU to have this process done.


496 Magnum HO Stage 2 Kit
Your Price:
$707.99

496 Magnum HO Stage 2 Kit

485MK-5355

496 Magnum HO Stage 2 Kit

With full PCM control, we can offer customers many different options for stock and modified engines. Whether its the Stage 1 and 2 packages or custom calibrations for your application, we can easily handle it with incredible accuracy and a ultra fast turn-around time.

The Stage 2 maximizes the power output of the stock engine by running 91 octane or better, increasing the maximum spark advance, increased ignition power from the individual coils, denser air charge from the low temp thermostat and maximized air-fuel ratio in each individual cylinder. Calibration increases torque levels throughout the entire rpm curve while making more peak hp for increased speeds.

    Key features:
  • Hi-performance PCM calibration
  • Low-temp thermostat
  • 5450 RPM limit
  • 5% - 8% power increase over stock
  • Increased acceleration with increased torque output

NOTE: You will have to remove and send in your ECU to have this process done.


8.2/502 Mag Base (DTS/ETC) Stage 1
Your Price:
$755.99

8.2/502 Mag Base (DTS/ETC) Stage 1

485CM-82MAG1D

8.2/502 Mag Base (DTS/ETC) Stage 1

A whopping 50 horsepower and 35 foot pounds of torque increase while maintaining use of 89 octane. This works with both the mechanical cable and digital throttle (DTS) as well as engines equipped with and without catalytic converters. This performance calibration of the stock PCM features a 250 RPM limiter increase and a revised fuel and spark curve to better enhance performance.

NOTE: You will have to remove and send in your ECU to have this process done.


8.2/502 Mag Base (DTS/ETC) Stage 2
Your Price:
$850.99

8.2/502 Mag Base (DTS/ETC) Stage 2

485CM-82MAG2D

8.2/502 Mag Base (DTS/ETC) Stage 2

A whopping 75 horsepower and 55 foot pounds of torque increase with the use of 91 (or higher) octane. This works with both the mechanical cable and digital throttle (DTS) as well as engines equipped with and without catalytic converters. This performance calibration of the stock PCM features a 450 RPM limiter increase and a revised fuel and spark curve to better enhance performance.

NOTE: You will have to remove and send in your ECU to have this process done.