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I have obtained a 1994 Verbitsky 15 FAI engine that appears to be almost new! Can someone give me a report on the engine and it’s performance? If I where to fly it in classic gas what plane would be recommended?
Thks, Scott
They were generally considered dogs. I will be glad to relieve you of it and save you the embarrassment. 😀 😀 😀
Hmmmm, I’m not sure Dean is telling the WHOLE truth there……………
I don’t recall where I heard or read it, but I believe they have something of a reputation for frailty – in particular they do not like to run lean AT ALL.
That said, of course, they are very powerful, fast revving engines.
John
I would guess that’s a pretty powerful engine, so I would choose an airplane around 600 sq. inches — or pretty well anything designed for engines like the K&B 3.5. The Pilfered Pearl 566 (or thereabouts) and the Astrostar 600 are two that come to mind. I believe NFFS has plans for both. That engine was designed to run on FAI fuel, so if you are running nitro you will likely have to add a head shim or two.
On the other hand, maybe you could sell it on e-bay for big bucks from a collector and buy a Nelson 3.25, 3.5 or a few K&Bs!Hi,
John is correct, do not run this spec’ of engine lean, the rear bearing is fragile, and also the piston are sensitive to over heating and could swell.
Prop it for at least 30k, (let it breath for the BHP) so do not use more than 10% Nitro because it won’t rev any higher regardless of head clearance due mainly to the fact that Nitro Methane burns at a slower rate than Methanol. So at these rpm’s, (where the engine is designed to operate on FAI fuel) you risk pre’ detination in compression – ruined motor!
Remember its a top end FAI motor so choose an FAI – low drag, sturdy design to match the rev’s/ prop’ combination, (this motor was designed for short motor runs). From my experiance an average example will rev’ higher than any stock Rossi 15 ABC, and a good example will be up with Nelson 15 SE’s.Thanks to you all for your welcomed comments and recommendations!! The motor is set-up for flood off and crank case pressure. What type of oil would be recommended, Full syn. or mix of syn.castor?
Thanks, Scott
I would use 12% castor and 8% klotz techniplate, 10% nitro methane and a balance of methanol.
The more I think about this, and especially after ASC’s thorough and very understandable evaluation, a better option is to off-load this dubious but powerful device on someone thinking of getting back into F1C. As luck would have it, I know just such a person.
John
Sound advice from John – a Cox/ K&B Conquest could be a better solution.
Andy
My opinion, for whatever it is worth is to do the following-
1.) Run it with a 7 x 2.5 or so prop-
2.) run it on 80% alc/20% synthetic (Klotz or equiv.)
3.) Use a bladder and flood it
4.) Stay away from the nitrated fuels as it should be strong enough for whatever you intend to put it on- but, if you do feel the need, shim the head at least .005-.007″ if you want to run 10% or so.This thing should be a great A Gas engine. Let it crank tho, prop wise…
I agree with John with only one major comment. Eugeny Verbitski (and all the other Russian and Ukranine engine builders I have spoken with) recommend ONLY Castor oil and not any synthisic oils. All these engines were designed for Castor since the synthetic oils are very difficult to buy in Russian and the Ukraine.
As John said, 80/20 fuel is the design-base fule for these engines, but by adjusting (lowereing) the compression, you can run 10% Nitro fuel. It has been my experience with the VE and other Russian and Ukrainian F1C and F2A engines that there is very little gain, if any with 10% N fuel in these engines.
Ron Bennett
I do somewhat agree with Ron- even tho I have been running the Klotz in all our F1C engines with (so far) no detrimental effects…However, I can tell ya to NEVER clean out an engine with isopropyl alcohol…..There is a story here and it would show my stupidity….Remember that isopropyl has a ton of water in it…bad for bearings and other things….
BTW Ron- lots of good comments on the Sympo and you were a part of it!!
The engine in question was designed to run on castor to meet the FAI fuel mix rules which only allow this lubricant (no synthetic oil). I like klotz as an addional lubricant in open/ classic fuel mix’s because it breaks down, ‘gases’ at a much higher temperature than castor therefore, better lubrication to the engine at high rpm’s/ running temperatures. I’ve blown several Russian engines by launching them to lean in FAI comp’s – 7 sec run days and the castor had vaporised – one melted piston or a rear bearing that spat its balls out at the piston.
A Nelson also gets round this problem!!!!
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