Looking for Opinions on RV-7A engine pros/ cons
 

Hi all ,
Even though I've built and am just out of the restricted Flt hrs on my RV 6 , ( o-320 / FP). I've taken on a RV 7A project and I'm sold on the idea I need a constant speed prop and at least a o-360 on the nose of this old guy A/C, I'm kinda stuck because I have an opportunity to buy an angle valve I0-360 but i'm worried about the issues with the nosewheel collapses and how much extra weight I can hang up there! I've researched and plan on installing the anti-splat nosewheel brace but don't want to create problems that can be avoided while building my last airplane !!
One last thing I should mention is the plane will be operated out of my grass runway , hence the nose gear concern
Any ideas and opinions would be greatly appreciated , cheers Garry.

Hi Garry,

I finished an RV7A with 0-360 180HP (converted to fuel injection) and CS hartzell prop. It is a very good performer and well balanced. It came in on the heavy side empty but I easily navigated a modest gross weight increase from TC. While a lighter plane would undoubtedly fly better (weight is the enemy), this one flys great and better than anything I was used to. I would not change a thing. A 200HP engine would be heavier still and not necessary in my opinion.

I did make some improvements to the nose wheel including:
-Grove 3-piece axle
-RV10 nose gear fork (custom machined to fit)
-500x5 nose tire (380x150-5 main tires)

It rolls around easily with one hand on hard surfaces and handles the grass strips with ease.

Bevan

get a hacksaw and cut off the nosewheel. You probably will want to move the mains forward a bit after that, and install a tailwheel.

From an operational perspective, a 180hp, parallel valve engine is plenty. From 190kts to vertical you have 2,000' of penetration. From a standing start, you are airborne as the throttle is applied to a count of 3.

Putting an angle valve motor increases weight, increases fuel burn for little or no added gain all around.

Now, if you were saving $10 or 15k on the motor on offer, maybe. But personally, stick with the original spec from Vans and you will not be disappointed.

Add the weight and you may be.

If the angle 360 is a truely sweet deal... you could minimize the weight gain on the front wheel by component choices, light weight starter, alternator, composite C/S prop (why degrade the 200hp by hanging a composite fixed pitch as greatest plus of using this engine would be increased climb rate?), etc. Move any weight you can aft, like battery, under panel stuff, etc.
There are a lot of 'A's operating off grass, proper Pilotage & maintenance keep them operating safely.

Garry,
Don't worry about the weight. My 7 weighed 1099 with the angle valve. I have flown 7's with 180hp fixed pitch, 180hp constant speed and 200hp constant speed, I would take the 200hp constant speed every time if I had the three of them in front of me every time( and I do ). If the engine is a great deal, I would do it in a heart beat. All this said, build the plane you want, not what others want you to build, all are great choices.

Thanks for the prompt reply's guys
 

All good advice , and I did see that not much was gained by the extra HP , I really am struggling with this call with our currency were it is ,,,,but the motor can be had at a good price so I thought I'd throw it out there to see if any one had made the journey , have to make this decision soon !
Thanks again!

Just another datapoint, I found a good deal on an angle valve. Coupled it with a lightweight whirlwind prop and light starter and couldn't be happier with the performance for the price. Cg worked out great. Can't speak to nose wheel issues as I've got a -7.

Another consideration is the Lycoming Thunderbolt 190.
Mine is in a 7A with an MT CS prop and anti splat, great combination.

Bevan:

"...but I easily navigated a modest gross weight increase from TC"


When did you accomplish the increase? I was under the impression the MD/RA and TC would only entertain an increase if Van's would put their blessing on it.

I'd like a 50 lb increase in GW on my 7A. (Not that I really need it, but it's easier than shedding 30 lbs from my midriff..)

Thanks

John