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New purchase IO-360-M1B but which injection and why?

rsr3

Well Known Member
Hi everyone

I’ve read the positive reports of the new FM-150 system from AFP. I like the sound of that. Does anybody know if there is a price difference when specifying AFP over Avstar from Lycoming new from the factory?

Also, is it mainly just the fuel control assembly that is different to the stock Avstar injection?

Cheers

Rob
 
I hear of late that the AFP FM-150C will be the standard system on the IO-360-M1B. In other words you would have to specify something different if wanted. I also understand the FM-150C does not bump the price. But, be ready for sticker shock on the engine…

I replaced my AVStar fuel manager with the FM-150C several months ago. I’m very happy with it. The kit Don put together for control linkages and such is first class as well.

Carl
 
I have had both Avstar and FM150 (different plane) and like the FM150 much more. When I bought my engines, there was no price difference.
 
Thanks Carl, it was your reports of the AFP that got me thinking about it. I’ve gone round the houses looking at different engines and want to keep it as standard as possible now… so going Lycoming from Vans rather than aero sport power. First build, don’t have the knowledge or experience yet.

I had a message from Matthew at Vans today that said the engine now comes as stock with the Avstar and the only way to spec AFP injection would be to go the Thunderbolt route. I can’t justify that cost and nor can I really see the benefits that offers.
 
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Questions

So what is better about FM150 vs Avstar? Issues or some data please?? I am asking because I have a Lycoming Thunderbolt IO360M1B with 40 hours. When I ordered in fall of 2020, i don’t think it was not quite available. So why would I consider changing ??
 
T
I had a message from Matthew at Vans today that said the engine now comes as stock with the Avstar and the only way to spec AFP injection would be to go the Thunderbolt route. I can’t justify that cost and nor can I really see the benefits that offers.

Interesting as this is not what I understand. I hear there is a transition to the FM-150C in progress so perhaps a little more time to let the dust settle is in order.

Before you order I’d contact Lycoming and ask.

Carl
 
So what is better about FM150 vs Avstar? Issues or some data please?? I am asking because I have a Lycoming Thunderbolt IO360M1B with 40 hours. When I ordered in fall of 2020, i don’t think it was not quite available. So why would I consider changing ??

The AFP FM-150C was designed for Van’s “snorkel” engines and tight RV cowls. It went from prototype to production last year - so it was not available when you ordered your engine.

For data I apologize for failing to take hard before and after install measurements. I only have antidotal impressions. I had ~250 hours on my IO-360-M1B with the Avstar systems before shifting to the FM-150C. It performed as advertised. Shifting to the FM-150C I can report the takeoff roll at my home field is a little shorter as the wheels are off earlier. High LOP cruise is perhaps 0.2GPH lower for the same TAS. This last piece I did not understand as I figured LOP fuel flow was the defining measurement of engine power. I got educated that while this is the leading factor, other factors are involved.

In real terms this is reason to order your engine with the FM-150C but the price to install it on an existing engine would be (for most I assume) not viable. The exemption is if you could sell the Avstar to cover the cost. I can report the FM-150C works just fine with the Avstar spider and injectors.

The next step is to work the snorkel to get a reduction in back pressure. Very early days but promising.

Carl
 
Have you considered SDS electronic fuel injection?

Easier cold start, easier tuning, modern.
 
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Thanks

Thanks Carl, I am not particularly happy with the hot starts with the Avstar. I ran my old IO360M1B to 2154 hours with the old Precision fuel injection which I believe was the old Bendix design and was very happy with it.

So will have to think about changing next winter.

Mike, no I would not consider changing to SDS.
 
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