# Lazair on Floats with Rotax 185's needs more power, Ideas?

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#### pictsidhe

##### Well-Known Member
I love air die grinders. But only at work, where they have a suitably enormous compressor to run anything I want. 1/4" die grinders need far more air than home size cmpressors kick out. Anyone who's ever tried that would know...
Being a cheapskate dabbler, I use small, cheap 1/4" electric routers with the base removed. Works just like a 'real' die grinder but doesn't need a zillion CFM compressor.

#### n3puppy

##### Well-Known Member
I love air die grinders. But only at work, where they have a suitably enormous compressor to run anything I want. 1/4" die grinders need far more air than home size cmpressors kick out. Anyone who's ever tried that would know...
Being a cheapskate dabbler, I use small, cheap 1/4" electric routers with the base removed. Works just like a 'real' die grinder but doesn't need a zillion CFM compressor.
X2 on the air grinders if you have a big enough compressor

One of the nice things about the cable grinders I showed is they have interchangeable heads .
The 45 and 90 degree are really nice for shaping transfer ports. Working on small bores like the 185 the 45 degree is perfect for getting in the bore and putting a chamfered edge on the ports to avoid catching a ring edge.

#### Armilite

##### Well-Known Member
My ideas (from least to most expensive) are to:

1) Add a NOS kit to get more power from the engines to unstick from the water. Use it like a JATO that you can turn on and off. To me, this makes way more sense than nitro fuel.
=====> NOS kit + Plane = FIRE or Blown Engine at High Altitude!

=====> 3rd Engine is not needed, when you can Upgrade the 185UL's fairly cheap. A New Hirth F-36 (SOLO 210) 2 cycle 15hp is F-36 with Recoil Start & Re-Drive $2364.00 and F-36 with Electric start & Re-Drive$2964.00.
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3) Add a couple electric motors to the wings for extra thrust during takeoff. Set up right, they could be used as generators during cruise.
=====> Again More Cost & Weight not needed!

If you want to re-engine the plane, you might want to consider these with an ACE Re-Drive:

225cc Tillotson Performance Engine
=====> Yes, a re-engine with one of these 20+ Honda/Clone Engines with an ACE Belt Drive $669 works. The Honda/Clone GX200 6.5hp has been used on a few Lazairs already making about 15hp@5000rpm each. A Harbor Freight Predator is 212cc and$99.99 when on Sale, and with the upgrades needed which you can do your self for Plane use, is around $400-$600 depending on what you all do. I would use the Billet Needle Bearing Rocker Arms ($200), most don't. By their Dyno Power Graph at 5000rpm it's making 15hp. Its a 17 HP, 4-Stroke for$750. Adding the ACE PSRU will about double that. You may want to consider propping it down to 13 or 14 HP for engine longevity. Between the extra power and larger props, it should solve the issue for you.
That $750 doesn't include the Header Exhaust. 225cc Tillotson Performance Engine Power Graph below. Probably not the best CAM for Airplane use. The Power Band is too High. You want the Power Band at 3000-5500rpm to look like this one does at 4600-6600rpm Smooth, no Blips. The Rotax 185UL just needs a Bigger Carb$40 off eBay and a better Muffler System that is less restrictive.

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