Frequently Asked Questions

We know you have questions. Which is why we continually develop this section to accomodate the latest and most frequently asked questions we receive on our products and technology. 


Frequently asked questions about the HIGGS DIESEL E-Series engines. 


Frequently asked questions about the Lycoming performance products. 

What accessories come with the HAWK V4?

Pricing for the HAWK V4 and all of the E-Series engines include the starter and alternator. A second alternator is available as an add on component.

What is the ECU/IGN kit?

The ECU/IGN kit is mandatory for any of the HIGGS products. We will not be able to sell any unit without the accompanying ECU/IGN components and kit. Pricing is shown on each product spec sheet.

Are the HIGGS products liquid cooled?

Yes, all of our HIGGS engines are liquid cooled. This is vastly superior to air cooled engines and provides for more regulated cooling in an aviation environment.

Do you have pricing available?

Yes, all of our pricing is published on each specifications sheet which can be found on our downloads page. Click here.

Are the engines Type Certified?

All of our products are intially for EAB and EXPERIMENTAL use only. We will likely pursue type certification for certain models. We will make announcements regarding type certification soon. 

What propeller types are available for the HIGGS enigne?

Type ‘N’ and Type ‘E’ flange hubs are available for the entire line of HIGGS engines.

Are any accessories included with the engine purchase price?

Yes, the base price for all of the HIGGS engines include the starter and alternator components. An additional alternator is available as an add on component by request. 

Is the HIGGS Diesel a wet or dry sump design?

All of the HIGGS engines are dry sump designs. A header tank or reservoir is required. Volumes by engine will be published and updated to each spec sheet when available.

Can I select my own ignition or ECU?

The HIGGS line is designed and optimized to run with a FADEC style ECU and IGNITION kit. This kit is mandatory in your HIGGS engine purchase. The kit includes dual ECU’s, Coils, Harness and Fuel Injectors. The builder or OEM will need to source the fuel pump and we will provide recommendations for pump specifications.

Do I still require baffling for GLADIATOR & CENTURION cylinder installs?

No, you can eliminate your baffles entirely when converting to the GLADIATOR and CENTURION cylinders. You do though need to plan for a cooler to manage engine cooling. This can be your existing cooling inlets as the source or naca scoop.

Can you use a narrow deck Lycoming core?

No, your core must be a wide deck Lycoming case. This can be defined by an ‘A’ or ‘E’ at the end of your serial number or a HEX nut style base nut. This is applicable for the 360 and 540 variants. Lycoming 320’s are also acceptable if originally designed for 160hp from the factory. 

Do you sell kits direct to the builder or build shops?

Lycoming performance products are available through approved build centers only. You must fly-in or ship your unit to an approved build center for overhaul. 

Do you have pricing available?

Yes, all of our pricing is published on each specifications sheet which can be found on our downloads page. Click here.

Are GLADIATOR and CENTURION Cylinders Liquid cooled?

Yes, the very intention of our products is to eliminate shock cooling, excessive heat by inefficient air cooling and poor baffling.  

Are there any weight savings when installing the liquid cooled cylinders?

Yes, there are significant weight savings. In fact you will save 7lbs per cylinder over your air cooled counterpart. That’s 28lbs of weight savings on an IO-360 and 42lbs of weight savings for the IO-540.


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