horsepower

Just saw the news about a 7.0 earthquake in AK.  Hope all our Alaska folks are ok!

Mark

 

Hello

If your Kitfox was parked a couple planes down from Pauls Avid, its one of nicest I have seen! I spoke with Paul about using the the engine on the Ridge Runner and have absolutely no doubt that if it is propped correctly, he would be pleased that he selected the HKS. I introduced Paul to a friend of mine that has an HKS for sale. He had the engine on his Rans S7 and though it was the most trouble free of the three engines he has had on the plane, it wasn't enough horsepower for the kind of performance he was looking for. Thats not to say it didn't work, it flew the S7 fine but the performance was only comparable to a Cub or a Champ. 

My Avid had the 582 originally and I flew it till TBO and had to make a decision wether to spend the money on the overhaul or switch to the HKS. I studied the torque curve of the engine and compared it to the 582 and on paper it seemed feasible. I then talked to Richard Kosi who had just won an award at OSH for his HKS powered Jenny and he convinced me that if the engine would work on a machine with such a high drag bucket, it would certainly work on an Avid. I then talked to a fella that had the engine on his Skyraider and that convinced me to go the HKS route. Even though his engine was under performing (he had dual exhausts that were not tied together, no scavenging, no balance, etc) he still flew it from OSH back to California with himself and another person in a little jump seat that was in the back!

This fella sent me allot of pictures of his install and that was the basis that Jim Carruthers used to fabricate the install on my Avid. Jim is a craftsman of uncommon ability and I am fortunate that he lives just down the road. He has the gift of seeing the cause and affect of how one thing is going to affect another and so he did the complete install, motor mount, cowling, exhaust, oil tank, ignition, etc, etc, one time and it turned out perfect. The only teething pains we had were with regards to the exhaust.

We started with stainless and it proved to be to brittle. I taught Alex Borla how to fly and eventually became their company pilot. They make stainless exhaust systems for cars. Alex was supplying me the materials and so it wasn't a quality issue, its just that with the heat cycle of such a compact installation, and the vibration of the engine, the exhaust needed to be fabricated from mild steel. So Jim fabricated it from mild steel and the cracking issues stopped. Jim also fabricated a bracket that suspends the muffler can from the engine itself so that the whole assembly moves in harmony and that is a must for avoiding cracking issues. The original HKS muffler only lasted 140hrs but I think I may have caused that. I was using copper anti-seaze on the joint between the header pipe and the muffler and the can turned to rust. Dis-similar metal electrolysis! Jim rolled a can out of 18 gauge mild steel and that problem was solved.

As for the propeller, and I think this is critical for the success of the install, it needs to be an efficient long two blade prop that can absorb the torque of the engine. I am using the same 71 by 37 Peery Prop that I used with the 582 and its perfect for the HKS. It allows the engine to spin up to 5700-5900 on takeoff depending on the day, and that is right in the meat of the torque curve of the engine. Out of curiosity over the years I tried a Powerfin and a GSC and they grossly underperformed the Peery. And I do mean grossly underperformed, night an day difference. My friend Joe Maynard has a two place Hiperlight with an HKS and an Aerolux propeller. I gave him a spare Peery that I had and he tried it. He said the performance was identical to the Aerolux so for anyone considering the HKS the Aerolux would be a good choice since Peerys are no longer made.

Whatever you choice, long and two blade is the way to go, 71 by 37 or 72 by 36. 

As for performance the 582 with the 2:58 gear box allowed the 71 by 37 Peery prop to turn up to 6100 rpm on takeoff. As I mentioned the HKS with the same 2:58 ratio gearbox allows the 71 by 37 Peery to turn up 5700-5900 depending on the day. Based on the same weight this equated to my rate of climb with the 582 to be around 1200 fpm and with the HKS I get a solid 700-900 fpm depending on the day. Not considering fuel flow, overhaul time, maintenance schedule, etc, this is the only performance parameter that was affected by the conversion. The weight of the plane after the conversion was a few pounds lighter. My avid weighs 530 lbs. 

I live and fly the Avid in the midwest and the performance by far exceeds what is required to fly around here. If I lived in the mountains, I would want more horsepower. 

A few years after I had the conversion done I had a lot of folks asking about the performance so I shot a video of the instrument panel on a flight and posted it on Youtube. Here is the link: https://www.youtube.com/watch?v=IOnOrQKaH6M

The HKS has been on there 12 years now and I have 650 hrs on the engine. Its brought me allot of joy and I am very happy I decided to make the conversion.

Mike Ricketts

Tjay

was that powerfin prop built for 912 or 914?  I have not seen one that long. If it's for a 912 then the rotation is set up for right instead of left  correct?

 

do you have a # for Roger Dunham or Charlie Brown?

 

i found olmsteads Sky ranch the # listed is 208-263-0354 it was for lee and Angie I believe I left them a message.

Has anyone had any experience with an ultraptop?

thanks

Jamie

 

 

 

Jamie,

Check to see if Roger Dunham is still down at Hackney Field in Athol.  He is a great guy, was doing tailwheel instruction in a Piper Vagabond.  He actually flew my Avid after I sold it to a guy in Spokane before I bought it back.  Hmmmm.... hangers are hard to come by in Sandpoint, check with Charlie Brown at Lee Olmsteads field north of town, he is pretty well connected in the area.  There may be hanger space in Bonners Ferry but I do not know many pilots up there.

By the way, I love my 2-blade 72" Power Fin Prop.  I have a 2.59:1 gear box and currently I'm pitched at 11 degrees.  I reduced pitch from 11.75 degrees to have a higher RPM at a slower cruise so I could comfortably fly with a friend in his slow as mud CH-701. The shallower pitch also gives me a better launch and climb.

MarkD

If I could find something for that price I would likely at least talk to the owner. The big issue is that this guy is willing to talk about a trade. I don't have the money to sink into another airplane after the loss of the Pursang. I haven't worked in three years and besides the loss of the Pursang no one wants to hire someone with a double accident on their record, even if they were both proven to be purely mechanical and the NTSB told me I did an "excellent job" of putting both planes down where and how I did. 

You say you knew of a B model on the left coast? That's still a big area! I've looked for Ridge Runners, Sky Raiders, etc with no luck on either end as well. 

Emory Bored, you are correct that the Champion is open, no doors, and open rear of the cockpit above the back of the seats anyway. Still has folding wings. Basically from what little I can find online it's a smashed width cabin with the same wing design. I have no idea of length of the wings though. Just haven't seen much information even with Google's help. 

 

  Damn Doug, you spent some time on that one hahahaha.  It's all good.  As long as I come out of it being able to have my daughter when  I am home everything else is trivial.  Retirement is a long long ways away and I can start over and still make the cut off date