Forum,
I'm trying to make a decision about what to run for a fuel system. This decision is completely based on the cost/benefit ratio for my application so having good information is the first step in making a good decision.
The engine I'm working with is a IO-540-C4B5 that mounts the fuel system vertically so I can run a carb or FI, secondly, my fuel system can be gravity fed (I'm building a bearhawk, and live in Alaska, but find this forum to have a wealth of info for any homebuilder) so I don't need pumps if I run a carb.
First I would like to compare the benefit of FI over a carb. This is my current list, can someone who has more experience comment or correct it?
Pros:
Better throttle response
More even EGT, perhaps smoother
More even temps allowing LOP operation
Better fuel economy based on LOP operations
No carb heat
Cons:
Cost is much greater
Requires fuel pump and boost pump
More weight
Local support isn't as good
Throttle response is not a big deal, but weight, cost, and complexity are, so the question is, will a FI system give me enough fuel economy benefit using it LOP to offset the cost, weight, and complexity? Could I honestly expect 20% more economy over a carb? Can I run the carb LOP as well?
Second, if I do go FI what are my options for systems? I know I could go lycoming/bendix, silverhawk, and airflow performance. Am I leaving any out? The Ellison kits don't seem to support 250+hp engines anymore. Any of these I should avoid? I really want a set and forget solution.
Thanks,
schu
I'm trying to make a decision about what to run for a fuel system. This decision is completely based on the cost/benefit ratio for my application so having good information is the first step in making a good decision.
The engine I'm working with is a IO-540-C4B5 that mounts the fuel system vertically so I can run a carb or FI, secondly, my fuel system can be gravity fed (I'm building a bearhawk, and live in Alaska, but find this forum to have a wealth of info for any homebuilder) so I don't need pumps if I run a carb.
First I would like to compare the benefit of FI over a carb. This is my current list, can someone who has more experience comment or correct it?
Pros:
Better throttle response
More even EGT, perhaps smoother
More even temps allowing LOP operation
Better fuel economy based on LOP operations
No carb heat
Cons:
Cost is much greater
Requires fuel pump and boost pump
More weight
Local support isn't as good
Throttle response is not a big deal, but weight, cost, and complexity are, so the question is, will a FI system give me enough fuel economy benefit using it LOP to offset the cost, weight, and complexity? Could I honestly expect 20% more economy over a carb? Can I run the carb LOP as well?
Second, if I do go FI what are my options for systems? I know I could go lycoming/bendix, silverhawk, and airflow performance. Am I leaving any out? The Ellison kits don't seem to support 250+hp engines anymore. Any of these I should avoid? I really want a set and forget solution.
Thanks,
schu