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-   -   IO-360 VS O360 (https://vansairforce.net/community/showthread.php?t=129293)

sheldon957 09-03-2015 05:06 PM

IO-360 VS O360
 
Looking at buying an RV7-A. It seems that 8 out 10 have a carb'ed engine.

Other than cost, what advantage if any would there be putting a carb'ed engine in instead of an injected?

Positives I know for injected:

NO CARB HEAT worries.

Better fuel savings

Better power.

I don't know if one is better than the other for hot starts.

guccidude1 09-03-2015 05:23 PM

IO-360 VS O360
 
I recently changed my RV-9A from a carb engine to to a FI engine, both -360s. My experience is no carb heat concerns and more equal cyl and egt Temps. Other than that, the two are a wash, except hot starts. Dan

N941WR 09-03-2015 05:53 PM

If you want to do negative G acro, then the FI wins. Positive G acro and a carb is just fine.

As for the better power, I seem to recall one of the engine builders stating that with their dyno pull's, the carbs tend to do better numbers.

I wouldn't avoid an airplane because of the carb as you can always swap out the carb, if you want to.

Chkaharyer99 09-03-2015 09:20 PM

I understand carbs typically hot start better that FI.

rzbill 09-04-2015 04:40 AM

Hot starting an injection engine vs carb as an issue is about the same severity level as the difference between the horizontal injection snorkel intake vs the vertical intake air box FAB.
By that I mean that the snorkel is way better in many respects (maint, cowl removal, fod) but there are thousands of people happily flying the FABs

sheldon957 09-04-2015 05:42 AM

How hard is it to switch over to injected? I guess you would need a new manifold, and the injectors, injector pump etc.

Also price guess?

Jesse 09-04-2015 05:46 AM

Quote:

Originally Posted by sheldon957 (Post 1011475)
How hard is it to switch over to injected? I guess you would need a new manifold, and the injectors, injector pump etc.

Also price guess?

You would need the injection servo, the spider (flow divider), the lines and the injectors. Then you would need to change the fuel system to high pressure, meaning the engine driven pump and the boost pump. Also, depending on the injection system you use, you may need a fuel return line going back to the tank. Total cost is probably about $4,000.

Walt 09-04-2015 06:39 AM

You will also need to replace most of the FWF fuel lines along with the throttle & mixture cables.

pvalovich 09-04-2015 08:43 AM

Carb vs FI: Hot Starting Fuel Injected Aerosport 360
 
There may be valid reasons to continue the FI vs carb debate, but hot starting a FI 360 shouldn't be one of them. The credibility of that statement is the fact I've been flying my Aerosport IO-360 RV-8A out of Inyokern (IYK) in the Mojave desert for 4+ years and nearly 600 hrs. with summer OAT's regularly well over 100 deg. F.

Here's what works for me - so far every time:

Throttle - Full Fwd
RPM - Full Fwd
Mixture - ICO
Boost - OFF (DO NOT PRIME)
Starter - Engage
Mixture - Move out of ICO
Throttle - Adjust after start (Pay attention or you will quickly find yourself at full power)
Boost - On if evidence of vapor lock at idle until normal fuel flow established

There may be other procedures, but the key for me on hot re-starts is not to prime - any priming at all seems to flood the engine. I use this procedure regardless of OAT for restarts. For initial start, I prime with boost pump 5-6 seconds..

Chkaharyer99 09-04-2015 08:55 AM

Quote:

Originally Posted by pvalovich (Post 1011512)
There may be valid reasons to continue the FI vs carb debate, but hot starting a FI 360 shouldn't be one of them. The credibility of that statement is the fact I've been flying my Aerosport IO-360 RV-8A out of Inyokern (IYK) in the Mojave desert for 4+ years and nearly 600 hrs. with summer OAT's regularly well over 100 deg. F.

Here's what works for me - so far every time:

Throttle - Full Fwd
RPM - Full Fwd
Mixture - ICO
Boost - OFF (DO NOT PRIME)
Starter - Engage
Mixture - Move out of ICO
Throttle - Adjust after start (Pay attention or you will quickly find yourself at full power)
Boost - On if evidence of vapor lock at idle until normal fuel flow established

There may be other procedures, but the key for me on hot re-starts is not to prime - any priming at all seems to flood the engine. I use this procedure regardless of OAT for restarts. For initial start, I prime with boost pump 5-6 seconds..

I'm going to give that a try. My experimentation has slowly trended that direction with better results as each time. Thanks

sheldon957 09-04-2015 09:18 AM

Thanks guys for the info. Much to think about.


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