View Full Version : Raven- redrive for car engine

01-12-2005, 05:23 AM
Hi my friend I was checking on the web about the new generation of 4 stroke
engine HKS and Rotax. We always have hear about Subaru engine all the time.

The good thing about Car engine is that is economic price, and more reliable than 2 stroke engine, any one can fix it with out been a aircraft mechanic and is easier for maintain. Just go to a auto part and get what you want.

Other good this is that 4 stroke engine is more economic burning fuel. Other thing is that Rotax has raise the price 20% more!!, (This guys are getting richer every time). We can say now that this is not a hobby no more, this is luxury way to past time. Well for people interest on using a car engine as aircraft this is :


01-12-2005, 06:37 AM
Hey Joe, that is what I am building for my 3DRV is a Geo with a Raven, it really is not turning out all that cheap, I will be doing thrust tests soon, I have the engine up and running, just making some changes to the airframe.

01-12-2005, 06:39 AM
David, How much you are already spend?

01-12-2005, 06:50 AM
I just made a chart to compare the Rotax with this engine:

Rotax 582/ 79.20 lbs/65 hp/ 89.1 lbs w/ transmition B/ 103.9 lbs w/ trans E/6800 rpm max/7.2 gph

Rotax 503/ 84.4 Lbs/49.hp/ 94.3 lbs w/ transmition B/ 102.0 lbs w/ trans E/6800 rpm max/6.8gph

Car engine competing with rotax 503

1000uls carb./118-125lbs/58hp@5700rpm/ 2.26 to 1/ 2.5 GPH @ 75 percent power

1000 UL or UL-T
Fuel Injected /135-138 lbs/ 62 hp* @ 5700 RPM/2.26 to 1 /2.0 GPH @ 75 percent power

Car engine competing with rotax 582

1000 RS
fuel injected/148 lbs/62 hp* @ 5700 RPM/2.26 to 1 /2.1 GPH @ 75 percent power

1000 RSX
Turbo/159 lbs/80 hp* @ 5700 RPM w/ 5lbs boost/2.26 to 1 /3.0 GPH @ 75 percent power

"The SuzukiŽ engines used in all the Raven applications are modern, liquid cooled, overhead camshaft, 4 stroke auto engines with proven track records of reliability while running at the rpm's encountered in our application (the 3 cylinder GeoŽ Metro engine turns 3950 RPM @ 75 mph highway speeds).

Longevity is also unsurpassed with courier drivers who use this type of vehicle for delivery trips regularly logging over 150,000 trouble free miles with only routine maintenance. Fuel efficiency in the automotive application is second to none with the 3 cylinder version of the car topping 55 MPG."

"With Rotax has to do a mayor overhaul every 300 hrs"

01-12-2005, 07:27 AM
I have flown a zillion hours behind and in front of Rotax 503 and 582 engines. Neither burns that much fuel per hour. They will come close to that if left at wide open throttle the whole time but throttle back to 75 percent and I get no more than 3 gallons per hour fuel burn in my 582.

01-12-2005, 07:29 AM
Ron I got the rotax info from rotax web site.

01-12-2005, 07:33 AM
that is fine, but I am just telling you what I have observed. About 2 gallons per hour for 447, 2.5-3 per hour for 503, and 3-4 per hour for 582.

If I were to be in the market to buy a new Rotax 582 I would instead buy a HKS. Only a little more money.

01-12-2005, 10:11 AM
Ok, well most of the published stuff is not worth reading, Ron is really close with his numbers for the 503 and 582, my burn rates were close to his but just a bit more, my machines could have been heavier or more draggy. 503 with nothing on them weigh 87lbs, with carbs and exhaust 98 lbs, 582 carbs and exhaust and radiator 105lbs, I weighed them just to make sure. Now the truth on the GEO/Suzuki with a raven redrive system. The engine itself only weighs 95lbs stripped. The ULs he does not do anymore, that was with the flex plate out of a automatic transmission, he says to many resonance problems, you have to go with UL or UL-T....I have the UL and with his lighten flywheel and all it comes to 140lbs, and I cut alot off my intake manifold for the TBI (by the way he was furious when I did it, but now he is ok with it since it is running fine) I believe all these manufactures and such fudge there weights ALOT. I don't care what Jeron says over at Raven, I did all his lightening techniques and cut down the manifold more than he recomends (cut off the egr, preheat pot, removed the manifold system that circulates hot water in the TBI) and still came in heavier than he shows. I am also running a 65 Warpdrive and did not like that at all either. Just as I have run it so far (fixing a tach problem) at 75% power myself (210 lbs) and a buddy (260 lbs) chock blocks could not keep it from moving. Thurst test to follow as soon as I get the tach situation fixed. It is heavy but talking with the guys on 3 different GEO groups who are flying them, using Raven or the Cezch SPG2 gearbox weights are the same (wish I had known I would have gone with the gearbox, instead I believed the 118lbs story from Jeron) and they are getting from 340 to 375 lbs of thrust depending on prop. My Redrive was $2200, GEO engine from JDM dealer $335, WarpDrive prop $520, Exhaust header $200,TBI/intake/engine harness(which takes alot of modifying took me 6 hours)/ECM and fuel pump came to $400 so the grand total of $3655.00. I will post more updates on the Geo when in the 3DRV thread as I progress.

01-12-2005, 04:23 PM
that is fine, but I am just telling you what I have observed. About 2 gallons per hour for 447, 2.5-3 per hour for 503, and 3-4 per hour for 582.

If I were to be in the market to buy a new Rotax 582 I would instead buy a HKS. Only a little more money.

Today I flew Cross Country over Charlotte to Lake Norman Airpark to show some guys my gyro. They are wanting to build a Dominator. It was a 52 minute flight over there and I cruised at 65-70 mph airspeed, 5600-5800 rpm, and burned exactly 2 and 3/4 gallons of fuel. The flight back was 5 minutes longer and was slightly less fuel burnt as I didn't climb out as high for the return trip.

Mike Schallmann
01-16-2005, 07:20 AM
A number of years ago I built up a GEO Metro for aircraft use --it has never flown but I still have it and I am designing a "foldable" gyro to put on the rear bumper of my 5th wheel trailer. Now for the GEO Engine --all up weight ready to fly is 155# that includes all electronics --starter alternator and aluminum radiator and coolant. With a 60X38 prop it pull tested at 345# of thrust --with a fuel burn of 2.5 GPH at WOT. I think this is a great little engine --unfortunately other projects have kept me from pursueing its potential. I spoke with Don Parham several years ago about this engine --as they had developed a redrive for it. He lso likes the engine --but he had little sucess in marketing it.

About the resonance-- I also had the problem --it shook like the devil at 1700/3400/5100 RPM with my stock flex plate "flywheel" --I went to a stick shift flywheel and this reduced the vibrarion to a tolerable level--its still there but not bad.

I had several lengthly conversations with the late Lou Ross ( a real professional on auto conversions for aircraft). His company developed a redrive for the GEO --he also encountered the harmonic vibrations --he is the one who recommended the heavy flywheel to me. To prevent the vibrations from destroying the redrive he had to develop a vibration absorbing coupling between the engine and redrive gearbox -he was sucessful --but he also was unsuccessful in marketing this product. Upon his death his the company passed to his heirs --who promptly ran it into the ground and destroyed the reputation of a great aviation person.

Sorry to hijack the thread--but I like Geo Metro Engines !!

01-16-2005, 08:16 AM
my neighbor is getting a geo today that is going in his Fix wing thing. He has been looking at the one I have that is still in the car for now for about a month. I will post photos of it when we get it in the plane. He is not sure of what redive to use yet.

01-16-2005, 08:58 AM
You might want to suggest to him that he contact Abid at http://www.tampabayaerosport.com they sell the SPG2 gearbox, that come with alot of stuff I did not get like the exhaust, altenator mounts, engine mounts....really a good deal and it is $400 less than the Raven Belt redrive (that I was not so bright in buying) and the guys running the SPG2 gearbox come in at the same weight as I did but are getting 30 to 50lbs more thrust using a Kiev Hot Prop.

01-16-2005, 12:43 PM
He is calling them and can't get them. that is who I said to use too. SPG3 is out now lighter. I was thinking of using the Kiev hot prop on the MZ now that I need a new prop anyhow.

01-16-2005, 05:13 PM
I hear that is a really nice prop, lots of thrust. A friend on this airport had a rans S-14 that would do 93mph on a 447 (he has sealed all the gaps and cleaned up every dirty draggy piece on it) and switch to the Kiev Hot Prop and now gets 109 mph. Not bad for a legal UL except for the speed.

01-16-2005, 11:09 PM
I thought part of a legal ultra light was a top speed of 63 miles per hour. Am I confused again? It seemed to me that anything that had the capibility to go faster was not legal. Thank you, Vance

01-17-2005, 03:32 AM
Vance read it he saud except for the speed. you are not confusesd just not reading.

01-17-2005, 07:57 AM
Vance?????? The last line says it is a legal UL EXCEPT for the speed.

01-31-2005, 07:54 AM
The Topic had wandered off into Pitot/Static territory, so I split off to here:

Airspeed vs. Fuel Burn (http://www.rotaryforum.com/forum/showthread.php?t=3618)

02-01-2005, 03:42 PM
We have a Suzuki RSX 1000 up and running but I couldn't reconcile with the weight although I found that the horsepower is every bit as good as suggested and may be even better. It appears to be every bit as good as a 100 hp EA81. (Will turn the same prop at the same rpm's with the same redrive ratio).
The ready to run weight came out at 182 lbs, plus radiator and water. This is a far cry from the 140 to 160 lbs including rad. and water as suggested. Given that the Rotax "E" box and starter combo is very weight efficient, I cannot see where the difference lies. I had to use a standard flywheel turned down to 9 lbs to minimise the low down pulse vibration problems. The engine was so course with the flex plate that it was not able to pull out of idle with a large prop. It still comes out 35 lbs lighter than an EA 81 Subaru (217 lbs) in equivalent configuration.
This is a follow up to the 600 cc 3 cylinder Suzuki that we already have flying very successfully, even with my weight (231 lbs). This engine would make an interesting comparison to the 912's.

02-01-2005, 05:18 PM
Tim that has to be the highest thrustline to pilot relationship I have ever seen on a gyro!

How much HP is that motor claimed to produce?

02-02-2005, 03:17 PM
Yes Ron - depending on the weight of the pilot and fuel, approx 6" to 7" offset. Not considered ideal but still a far cry from RAF's 12" to 14". Also has over 6 squ ft of H/Stab with a long moment arm.
Initial flight tests show a good comfortable cruise at 3500rpm at 60mph indicated, with over 5000rpm useable. Economy we expect to be exceptional and will post as soon as it has enough hours to get an accurate figure.

I think some quote the hp at 80 and 5 lbs boost. It certainly has considerably more than that @ 5000 and 8 lbs. I do not have any dyno figures but I will try to locate a graph from Suzuki.