Making my series 5 into my dream plane

[trentp]

Hey guys, after speaking with John from kitfox it was pretty clear that I needed to not just get more air to the cooler but I would need a larger one, since I had the smaller cooler for the 80hp engine. So I decided to try to avoid cutting into my cowl if I didn't have to and go with a larger oil cooler in a location that would get more air.

The new oil cooler is about 3 inches longer than my old one, which still wasn't very large so I decided to try running dual oil coolers. A friend of mine who is a welder came and helped me build a bracket to hold the new cooler above the gearbox. It took about an hour or so but fits nice and snug in there.

I went ahead and did a test flight (it was about 90 degrees out at the time) and found that I couldn't get my oil temps above 150, so I dropped 100 degrees by adding the additional cooler. A definite improvement but this was obviously too much so I went ahead and got rid of my original cooler, and went with only the larger one. I did another test flight and my temps jumped back up to about 180-190, still a little low but I think I would rather be too cool than too hot, now I can just work on blocking off sections of the new cooler until I get in the correct range. I was worried that I might end up blocking too much air coming into the cowl by mounting it above the gearbox like that and would see a rise in my CHTs but that wasn't the case, they held steady at 200.

So for now I am going to run it with the larger cooler mounted above the gearbox and see how it does. I am considering moving the larger one back below the gearbox and trying to make room for it but I am not sure if there is any real need to. Does anyone know if there is any reason not to run the cooler where I have it? (see photos below)

This is with both coolers, a little overkill


Here is where the new cooler is mounted, if I decide to leave it there I will get the brackets powder coated black to match the old ones. Is there any reason to avoid running it above the gearbox like this?

[Dusty]

Just. Thought !
Above the gearbox may give better airflow at high angle of attack on climbe out when I is most needed,under may be slightly blanked ?

[Av8r3400]

My plan is something like this...

[Slyfox]

absolutely, that's how mine is. except I need to finish off the cut. I haven't got around to it yet. that's how mine is going to end up when I get to it. that does work the best.

[Esser]

Trent, you waste no time that's for sure. All I would say about on top of the gear box is that if you ever want to install an external alternator, it will be in the way. Other than that I think it would be fine if you left it up there.

[Slyfox]

I installed my oil thermostat on top of the gear box. I really like the location there. to each there own. I know looks is very important to you, so I guess a double cooler is in line. should work out.

[trentp]

Hey guys, its been a while but I have been slowly chipping away with the kitfox upgrades. The latest addition, the shock monster gear from Kitfox!!

I figured I would post some pics of my work I did covering them before getting into my thoughts on the gear itself, it was my first time ever doing any fabric work and was far from perfect, but I figure since it will be dragging through bushes it is probably ok.

I liked the way the silver STi kitfox has its gear covered with the fairings on the actual tubes so I went the same route:

Fairings cut and set in place with Hysol:


SuperFil on the fairings to smooth the edges into the tubes on the gear legs:


Poly brush on the newly covered legs:


Painted gear!:


For the shocks I ended up with a new size that TK1 just started making, previously they recommended either a 1.5in shock or 2in shock depending on how heavy your plane is but inevitably the 1.5 was a little too soft and the 2in was a little too stiff, so they now are selling a 1.75in which is what I got.

Install was pretty straight forward, which was impressive since the series 5 does have different gear mounting points than the super sport so I was impressed that the gear legs fit perfectly.

Look ma! No gear!:


And Finally the finished product:






FLIGHT REPORT:

Ok, so now for the important part, how do the new gear perform and how they compare to the spring gear?

The bush gear sits 4 inches taller than the spring gear so any chance I had at seeing over the panel in a 3 point is gone, but the added height is great for keeping the prop out of harms way, especially in the sand and long grass/weeds. As far as the way they feel compared to the spring gear it really is a completely different beast. The spring gear is great in the way it absorbs impact, I don't know if any of you have watched someone come in and hit hard with the spring gear but the spring really does a good job of taking the hit, if I had to estimate I would say the spring gear has about 6in of travel at the wheels. The downside is that with the spring gear it takes a good portion of that energy of the impact and shoots it right back at you causing a bounce, this is where the shock monster gear is different. The actual impact will feel firm but then no bounce, even on harder landings it just sort of smacks down and is done, that, in addition to the bushwheels makes the plane a walk in the park to land, even if your flare isnt timed perfectly. Enough so that even the first real time I took out the kitfox flying with the new gear I went and landed on a hillside that I wouldn't have felt comfortable enough to land on with the spring gear just due to the fact that I didn't have the room to risk giving up to a bounce (the useable area on the hillside was about 300ft, and because of the uphill is plenty long, could still be short if you factor in a bounce or two). With the bush gear I was able to come in with confidence that I wouldn't bounce and also wasn't as concerned with the slightly rough surface of the hill.

The gear really does make bumps and rocks feel a lot less jarring, its hard to explain aside from just a complete different feel, no more bouncing and bobbing, just planted. I am completely sold on them for the type of flying I do.

The main downside I have found is the drag, I did lose 8-10mph with the gear alone For bush/off field flying they really do make a world of difference though, so I am willing to give up some speed to help protect the prop and the airframe when landing in the rough spots. I am going to put some fairings on the bottom of the shock tubes as well as on the "V" portion of the cabane to hopefully help reduce a little of the drag.

Some pics out in the bush with the new gear:


(that feeling you get when you can land but your friends have to circle overhead and watch):


Don't try this at home


You may have noticed that my "big" 26in tires don't look so big anymore with the bush gear, so it was time to upgrade. Unfortunately my single puck Cleveland brakes were barely cut it with the 26s so I knew I would have to upgrade to something with some more stopping power to try to stop the next size up (being 29in Airstreaks). John at kitfox helped me source the best set of wheels and brakes for my application and special ordered them for me from Grove. I just received the wheels and brakes on tuesday so I went out and installed them on wednesday. I was only able to make a short test flight with the 29s but I was surprised that they didn't knock my cruise by much at all. Must be because I already slowed it down with the gear

Size difference from 26in ABW Airstreaks to the 29in ABW Airstreaks:


Looks much better proportioned with the 29s:


And finally the very happy pilot (me) standing next to a kitfox with a newly improved ramp presence:

[trentp]

Next is the STi wing!

[DesertFox4]

Thanks for taking us all through the mod with a great write up Trent. Sounds like the combination you needed. Now a big bore engine upgrade along with the STi wing and look out back country. Looks great.

[trentp]

Thanks for taking us all through the mod with a great write up Trent. Sounds like the combination you needed. Now a big bore engine upgrade along with the STi wing and look out back country. Looks great.

Already have the big bore! So all I need is the STi wing now