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Engine Selection Assistance 7A

J

J832

I'm New Here
It's time to settle on an engine for the 7A and as a first timer I'd appreciate thoughts from the experienced guys. I've decided on 180 HP, fuel injected, CS prop, new non-certified Lycoming purchased through Van's with their Hartzell prop. On the configuration, my research has just produced more Questions. Dual Mags? Dual Lycoming EIS? Or Dual P Mags? And are chrome rockers worth the extra $400? This price increase deadline today was a surprise. I'd like to firm this up and get it ordered and save 13%. I'm in that place where you don't know what you don't know.
 
Oh man, you're gonna get so many opinions, and unfortunately no one can make this decision for you.

Dual Mags: Old school technology but if it passes the mag check on the ground, likely won't be the reason you crash airborne.

As far as I understand the Lycoming EIS vs the P mags is that they're pretty similar. Both are electronic ignition and both are self powering, so once they get going they'll power themselves. Just pick between which manufacturer you want. I think the P mags give you a little more control over the ignition curve, but Lycomings website is very limited on information about what their EIS actually does besides "drop in capable replacement for magnetos".
 
You’ve got a standard and popular engine choice, which will save you time.

I’ve never seen anyone post that they didn’t like the mag system they chose.

I have Pmags. I like the efficiency and the cheap automotive spark plugs and the support from the company. However I had an off-airport landing because I used a single wire from my power bus to a splice to the pmag power, and made a crimp that had a rare intermittent failure. Then I had the bad luck for this failure to occur while doing a stall at low I dle rpm when the internal pmag alternator wasn’t operating, and doing it too low to pitch down steeply enough to get the rpm up to restart. This was a completely avoidable mistake that I won’t repeat. Using one normal mag might have gotten me most of the pmag benefit and kept me in the air with true independent redundant systems.

David
 
agent4573 said:
As far as I understand the Lycoming EIS vs the P mags is that they're pretty similar. Both are electronic ignition and both are self powering, so once they get going they'll power themselves. Just pick between which manufacturer you want. I think the P mags give you a little more control over the ignition curve, but Lycomings website is very limited on information about what their EIS actually does besides "drop in capable replacement for magnetos".
Click to expand...

My understanding is that the Lycoming ‘Sure Fly’ is dependent on ship’s power, which is why they recommend keeping one conventional mag.
 
I had a conversation with Kevin at Van's who patiently explained all the engine options - very helpful. It made sense to go with the P-Mags although I have read about using one mag and one P-Mag which can be a good thing. I also chose the 72 inch prop since there is little or no performance difference and it provides 1 extra inch clearance. I do hope to be flying in the back country.

Thanks for everyone's insights.
832J
 
When is the price increase deadline? Im trying to decide between aerosport IO-375 and the engine you are buying. This may help me decide
 
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