-
Re: ea81 for model 3?
What???? my kitfox 3 with E81 mod was special built cowl...as to CG its 11.26 with 10.2 max forward and 14.28 max aft at 1050 # with 2 people 178# each plus 7 gallons fuel......flight time 250 hours on aircraft now...have no problem take-off or landing within 250 ft...1992 Rotax was unreliable hence the E81 :)
-
Re: ea81 for model 3?
Howdy all;
If asked, I guess I would say a 205 lbs EA-81 Subaru install is too heavy for a Kitfox-3, but then again someone else might say my 180 lbs VW engine install is too heavy for my model 4, then others have said the 165 lbs Rotax 912 install is too heavy. I guess every engine is too heavy for someone out there !!!
Regarding performance and reliability, the Rotax 912S is best for the Models 3 & 4, I think most everyone would agree to that, but I personally don’t have the $20K+ it will take to put a new one in, or the $10K it will take to rebuild it later, but I do have the $3K it will take to get a used VW and the $1K it will take to rebuild it and I think a good used EA-81 can be had for about the same money.
For me, when it comes to putting an engine in my plane, it’s “low-dough” or “no-fly”, it’s just that simple, and I don’t think I am the only one in that situation.
Roger
-
Re: ea81 for model 3?
Thank you Roger Thats another big reason I fly what I fly.....your so right
-
Re: ea81 for model 3?
I know the guy C5 is referring to. We became friends because I worked in the city where he lived and except for the engine, We were building the same airplane. As I understand, He chose the EA-81 because NSI never published service bulletins and the frequent ones from Rotax bothered him a bit. He was retired airline and could have afforded any engine. His plans were to fly it out of his home strip which was on a vineyard. Actually at the time we both started, the factory was supporting the NSI EA-81. Then for some reason they stopped the factory support. The airplane's performance disappointed him some as the hours would indicate.
I am always intrigued by the cost of overhaul being entered into the discussion. I bought my present project 80 horse Rotax used with 150 hours for $9000. With my first airplane, over nine years I flew 900 hours or approximately two hours a week. For me, at that pace it would take 20 years to consume the TBO hours. In that time, I'll need a new roof, and maybe a casket or two. If you are like Ray Volk and put a thousand hours a year on your airplane, I can see the concern. I know a few who put a couple of $$ in a "can" after each flight for the future. I do understand budgets though. Being retired, the cash flow is not the same as it once was and my present project will likely price out at almost the same my 19 year old project did. It can be done.
Lowell
-
Re: ea81 for model 3?
Plus with dual exhaust with mufflers the E81 is so quite plane is stealth and headset not needed except for radio calls
-
Re: ea81 for model 3?
Hi Skydave , I have bought a avid + project and it came with Ea81 and I am working on getting it install. It's great to hear some positive info on the soob.I cannot afford a 912 right now so its full steam ahead on hanging the soob on.I just got my TBI-40 carb today for it and almost have the cowling fitted on.
-
Re: ea81 for model 3?
not familar with TBI-40 carb used a ford bronco carb on my E81
-
Re: ea81 for model 3?
I am still hoping to buy a Kiftox VW firewall forward setup off a guy with a flying VW powered Kitfox. His 3 Avid buddies fly the EA-81 and like it so much that he is willing to swap engines out and join the EA-81 club. Plus, they gave him an EA-81 engine for free!!!
For me, it’s kina like “better the devil you know” as I have had several VW engines and know the strengths and weakness best, and what to look for in general. Plus, Great Plains VW is less than 4 hours from my house, so I can pull the engine and drop it off if needed.
If I can get the VW setup, I plan to change the engine from 2180cc to 2273cc, and drop the compression to 7.5:1 so I can run 87 octane car gas. Also, install aluminum cylinders to save an extra 10 lbs off the engine weight (it also helps cool the engine), which will give an install engine weight of about 170 lbs with about 75 HP peak for takeoff, and burn about 4.5 gph at cruise.
Roger
-
Re: ea81 for model 3?
Hi Dave;
Great video of the two kitfox, nothing like a side by side comparison.
I think the VW direct drive (the 2180 cc) setup produces about 25% less static trust at take off, as compared to a 582 (as I recall). So the take off role of the VW craft would require about 25% more time to reach lift off speed (using F=MA). So if the 582 can take off in 4 seconds and covered 264 feet (for example), I would expect the VW kitfox to require a take off role of 412 feet (if I got my math right).
Of course, this assumes the 582 can maintain the same 25% greater static trust level over the VW prop, which it probably can't as one property of a flat pitched prop is that the static trust drops off quicker than a more pitched prop as forward speed builds, so these numbers are or more like worst case for the VW.
Below are the actual performance specs from a flying VW powered Kitfox-4 that was up for sale last year (The 32" pitch on it would be consider pretty flat for a VW (my Sonerai had a 46" pitch on it))
Hope this helps
Roger
Specifications N53RJ KitFox IV Speedster
powerplant
propeller
length
height
wing span
wing area
seats
empty weight
useful load
gross weight
fuel capacity
range
Great Plains VW Direct Drive 2180cc 76hp
Ed Sterbra Wood 62x32
17.8ft
5.8in
28.8ft
116.8sq.ft
2
700lbs
500lbs
1200lbs
27gal
570nm
Performance
takeoff distance, ground roll
rate of climb
max speed Vne
cruise speed @ 7500 msl
fuel consumption @ cruise
landing distance, ground roll
service ceiling
300ft
1000fpm Single Pilot, 700fpm Dual
140mph IAS
110mph TAS
4.5gal/hr
300ft
11500 ft
Limitations
design manoeuvring speed (Va)
never exceed speed (Vne)
stall, power off (Vsl)
landing approach speed
106mph IAS
140mph IAS
37mph IAS
60mph IAS