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145 hp??

B

Billythekid

Well Known Member
my eaa has a continental 145hp o-300-b motor with all the stuff fwf for sale at a great price. I haven't done any research in the motor yet but my question basically is... am I a bad builder for sticking a 145 hp motor on a rv4. missing 15 ponies is 10% but I learned in a lynx with 115 hp so it got me thinking, what say you? for less than 5k I'm fwf just trying to learn
 
I'd guess you could, but I also guess you will not be happy with the results.

Side point - will the Continental even fit the Van's engine mount? If not, then the cost to modify will blow away any savings you might have with this engine.

Carl
 
Lots of -6s and -7s out there with 150HP and happy.

EDIT: Apparently not just about HP, though!
 
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I'm no aerospace engineer and I didn't stay at a holiday inn last night.. just an RV-4 pilot that doesn't fly with my IO-320 RPM pegged. I would think with the appropriately pitched prop that you can have a fun and reliable performer.

With that being said.. fwf kits and most all of the challenges a builder would face with a lycoming have been hashed through in this forum which is a huge benefit imo. Also you may want to consider resale cost.

I hope you get responses from some of the more knowledgeable regulars here on VAF or from those with 135hp powerplants.

Stan
 
I can't find exact numbers but I expect that those two extra cylinders would increase the engine weight somewhat.
 
0 300

The 0 300 is very heavy and the length of the engine will likely screw up your cg badly. ) 300 uses a bed type mount which is much more difficult to build than four cyl. I doubt you could get anyone to build a mount so you would be on your own there.
A Wittman Tailwind with 0 290, 125 hp, will run circles around a near identical Tailwind with 0 300, this is all parameters-takeoff distance, climb and cruise speed.
Don't believe much of anything about weight of 0 300. The Continental numbers are badly out of date. You have to put the engine on a scale to find what it actually weighs. 50# heavier than an 0 320 IIRC. The moment arm for the engine is way forward compared to the Lycoming.
This is a REALLY BAD IDEA especially for an RV4.
 
My 2 cents

I built my -4 on mega budget. I have a fair amount of aviation skills, and have seen a lot of interesting variations..my 2 cents is VANS and other resources make the Lycoming an easy, adaptable , all kind of stuff that bolts on , get-it -flying well machine. I am not against other adaptations , but most require deep re-engineering of mounts, induction and exhaust fitments, ect. I chose a Lycoming O-320H2AD for mine, which will get comments good and bad, but is a great engine, 160HP, bolts up to all the mounts, exhausts and only has a few items needing adaptation. I have 6K in mine, and completely happy...personally, I wouldn't even think about the Continental 6.
 
I've seen a few -4's with a continental engine and IMO, it creates an ugly arse cowling. Performance wise, I wouldn't deviate from from anything smaller than an 0320.
 
Of all the Tailwind engines Wittman tried, he liked the O-300 the best. I'm sure it would fly a -4 just fine. I built a bed type mount for an O-300 for my Tailwind and it took no particular skill if you know how to weld and use a tape measure.

That said, going with the O-300 just to try save a buck is false economy. Even if you got the engine for free, you would probably still spend more money and time on the conversion than finding a good used Lycoming. And thats to say nothing of the hit you will take at resale.

If you can use a 540 on a -4, then you can certainly use a O-300, and it would be a sweet ride if you did it right. But like the Rotec powered -8, "economy" is not the reason to do it.
 
I'd like to see one on a scale. Just because it has 2 extra cylinders doesn't automatically mean it's heavier than a Lyc 320. The Continental IO-360 (6cyl) is actually lighter than some Lyc 360's.

You can be confident that it will be a lot smoother than the Lyc.

It will be a lot of extra work, though, as others have said. Such a shame that this isn't about home *building* and experimental aviation anymore.....

Charlie
 
rv7charlie said:
Such a shame that this isn't about home *building* and experimental aviation anymore.....

Charlie
Click to expand...

Why not? A LOM just went on a 7 in Europe, a Radial on an 8 over here. It is what you want to make it. The OP asked and received opinions. Not all are going to be "go for it!", and from the sounds of it, for some very good reasons.
However, if the OP wants to "go for it" and do the engineering it will take, I am sure he would get a lot of support.
To your point, RV's, with some 9000 flying, don't have a lot of "mystery" left to explore. They have been pretty well rung out...
 
Weight a minute...

Billythekid said:
my eaa has a continental 145hp o-300-b motor with all the stuff fwf for sale at a great price. I haven't done any research in the motor yet but my question basically is... am I a bad builder for sticking a 145 hp motor on a rv4. missing 15 ponies is 10% but I learned in a lynx with 115 hp so it got me thinking, what say you? for less than 5k I'm fwf just trying to learn
Click to expand...

Billy,
Not to dissuade Experimenting but the guys are correct.
The 0-300D/C-145 were great engines in their day...They're relatively cheap, ECI does make cylinders and they do run very smooth.
However, a Narrow Deck 0-320 weighs less and can be bought for under 5K and self-overhauled for about the same amount and...Van's sells an engine mount and....it's proven over many thousands of hours by the designer and the list goes on not to mention the re-sale aspect mentioned above liberally. Another aspect is the cowling fit and CG issues from the heavier, slightly longer engine.
This same argument goes for the brave souls who have auto conversions in RV's or any other EXP (me being one with my Sonerai-2).

My 2 cents after 20 years and 3 RV's and a few thousand hours?
Buy a Lycoming..:)

V/R
Smokey
 
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Engine

The percentage of builders who could install a Continental in a reasonable period of time is a VERY small percentage.
One of the possible hurdles on a narrow firewall is that the oil pan on the Continental interferes with the landing gear truss. So the engine would be at least a little forward of optimum because of this.
Disregarding all of the previous advice, ask yourself the question: do I want to build or do I want to fly? A relative novice could literally spend years just on the firewall forward for the Continental.
 
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