Airtrikes SPG-4 geared PSRU

Joined
Oct 30, 2003
Messages
196
Location
Conway, Ar
Aircraft
Highly modified KB-3
Total Flight Time
950 Gyro - 200 FW
Does anyone have any knowledge about the SPG-4 spur gear redrive sold by Airtrikes? They offer a complete conversion kit for the Subaru EJ-22 that includes the bell housing, coupling/damper, geared redrive and all the hardware necessary to install. Their website advertises a 5 year / 500 hour warranty and designed for engines up to 180 HP. They have been in business since 2002 and have tons of pictures with the redrives on numerous types of aircraft. I haven't found any negative comments about the redrive or the company, but of course you wouldn't on their website. Does anyone know someone that is using one or knows anything about them?
 
I have one one your old EA82. I don't think it's geared right for the engine RPM vs prop I have, but the box looks of good quality. A few of the bolts I got with the kit were not the correct length, but that was easy to fix. You'll probably have to buy new flywheel bolts that are longer to accept the three prong hub piece. I would suggest allen head due to clearance issues.
 
Thanks for responding Bobby, I appreciate it. What gear ratio does your's have? If I recall correctly, the gearbox can be returned to them and they can put a different gear ratio in it. But as always, $$$$$$$. I'm thinking about the 2.03/1 ratio for my EJ22.
 
I emailed them. They said that the 2.43:1 gears were the only ones available for my box. 2.03:1 is exactly what I need. I'll have to contact him again and see what's up.
 
Bobby, I sent the deposit today for the SPG-4 with the 2.03/1 gear ratio.
 
Let me know how it pulls. What prop are you going to use?
I emailed them to see if they would let me exchange this 2.5 for a 2.0. He said he was out of country right now, but to email him in a few weeks.
Also, the box is made to be mounted with the thrust line "over" the crank. I had my adapter plate (bell housing) re-drilled so I can drop the thrust line below the crank.
 
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Did you get an SPG-3 or SPG-4 redrive? The SPG-4 bell housing is advertised as being able to position the redrive up or down or any other position from the crankshaft. The prop I'm using is a Warp Drive 4 blade 66". He said the 2.03/1 setup will take about 4-6 weeks to be ready to ship. I'll let you know how it turns out, it will just be a while.
 
I must have got the SPG-3 because the holes were offset and could not be flipped without re drilling.
 
Their advertising shows the SPG-3 for up to 130 HP and the SPG-4 for up to 180 HP. The SPG-3 will easily handle the EA82 so I'm pretty sure that's what you have. With the ground cams in my Ej22 I'm probably putting out about 142 HP so I went with the SPG-4.
 
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