What it looks like today.
What it looks like today.
Last edited by stewartb; 10-27-2016 at 07:02 PM.
Stewartb, glad to see it coming together,looks great. I'll be back home in Feb.- Mar. and would love to stop by and see it.
I just watched the Mustang video and here is the end of the season work, kinda like moose hunting when the shooting is done,lol.IMG_1297.JPG We pulled the engine for a rebuild , now waiting for it to come back is the pain. I love working on the old war birds, but flying them is better.
Bet you could get away with maybe 8-900 lbs. but the climb rate would make others notice,lol.
Memo from Mike. Written after to remind me of what we talked about before. Or maybe it was there but that side was facing the floor. Either way... Oops!
Last edited by stewartb; 11-08-2016 at 07:32 AM.
Baffles are mostly finished. Add a couple of blast tubes for the Pmags and fuel pump isolation box and the engine compartment is complete enough to step away. Time to tackle the G3X installation.
Looks very nice Stewart. At the suggestion of a friend, I actually raised the front of mine to be even with the cylinder mid-point. To my surprise, just that seemingly minor change dropped my CHT's significantly.
I put ramps on my cub. Started with metal tape and adjusted that over two years. When I had it right I made metal ramps I lowered them a bit taped them in place to make sure things worked as planed. Taping front gave me excellent control of CHT adding ramps improved it 10 more degrees with 234 all within 5 degrees of each other other in cruse #1runs 10 degrees cooler than the rest.. One side is higher than the other. I would not try this without CHT probes on all cylinders. A small amount of tape or ramp can make quite a bit of difference in temps. You could build adjustable ramps pretty easy I think it is one of the best things you can do for the motor
The IO-400 is supposed to have cool CHTs and warm oil temps with the big angle valve heads for cooling and piston oil squirters and cold air induction warming the oil. I'll deal with the CHTs by adjusting baffles and balancing the injectors. I think we have as good a handle on oil cooling as we can have. The baffles could take up several pages on my website. Maybe I should do a photo file for all build pics on Google Pics. When I get time.
Stuart, That looks like a solid engine choice but out of curiosity how does "cold air induction" warm the oil? Is it a way of taking even more cylinder heat and transferring it to the oil for dissipation?
As for baffle openings, from mass and heat transfer once upon a long time ago I seem to remember that increasing the velocity (which raising the baffle ramp heights would effectively do) over a cooling fin increases its cooling coefficient compared to large area low velocity air once a certain velocity is reached. Unfortunately, I'm pretty sure I was hung-over for the discussion of actually determining what that velocity is and I never took a class which studied high velocity inletss only sub-critical velocity inlets.
I like the blast tubes for critical areas but it would seem that having both critical tubes and the mid-cylinder ramp height (like the beautiful one suggested) could be benificial... This is challenging to me because I anticipate that you will have such a wide variation of intake conditions straight and level but not real fast, high AOA and finally to the ridiculously high AOA at very slow speeds that I could see the nose bowl possibly achieving the same effect at the high AOA conditions but you could also loose a great deal of inlet efficiency if the flow is greatly disturbed in that condition if sustained for long periods.
Overall a baffling question that I remember discussing with Wayne when I was his back seat test dummy for a few days in the early testing of the SQ-2. We discussed summer temps but that wasn't a concern those days the tears I shed from laughing at the incredible performance froze to my cheeks but I do recall he was planning a bunch of hot temp. testing and if he planned it, it happened.
Beautiful work on your project and a well offered a observation, my only suggestion is to keep all the arrows offered in your quiver as you move forward.
I look forward to seeing more.
Last edited by OLDCROWE; 12-10-2016 at 08:35 AM.
"Don't feed the hipsters"
Cold air induction doesn't run the induction tubes through the sump. Apparently those tubes contribute to oil cooling by transferring oil heat to intake air. But adding heat to intake air robs power.
Pressure cowls are an interesting thing. Velocity isn't everything. Sometimes it's better to slow down the air to allow heat to transfer better. Thus the attention to pressure differential. That's why I'll have butterfly valves in the outlets of my oil coolers. Playing with those will be telling. I've had to build air dams for the Cessna to help equalize temps between front and rear cylinders. I always figured I was moving some cooling from front to rear but never considered the overall cooling would be increased. The ramp thing is something I'll use if necessary. I hope the total cooling will be adequate and may only need to balance temps. More SQ guys struggle with CHTs than oil temps but typically they use hot-rodded parallel valve engines and streamlined composite cowls. My engine brings cooler CHTs and hotter oil temps. BCSC has struggled a bit with oil cooling in planes they've built with the IO-400. Dan @ HO warned me that one oil cooler wouldn't be adequate with this engine. I haven't seen anyone do what Mike and I have done with dual front coolers but I believe we have the best oil cooling potential I've seen to date. Part of the allure of the Cub cowl is to provide a known entity for cylinder cooling. The dual front oil coolers was designed on the fly. Come April we'll know whether we're on the right path or not.
Last edited by stewartb; 12-10-2016 at 10:40 AM.
Here's a side view of HO's IO-390 STC installation. This is similar to BackCountry's IO-400 oil cooler installation that I've seen photos of. Holy blast tubes, Batman! My 1" blast tubes will cool the Pmags and feed the fuel pump insulator box and the sum of three won't come close to what this picture shows going to the oil cooler. And HO has a second cooler in there, presumably on the baffle on the other side. If they can steal that much air for oil cooling and still manage CHTs I should be way good.
I missed that you did dual front oil coolers, mine had that set up when I purchased it. There was the standard stock (boat anchor) cub cooler and then anouther one (stern anchor) mounted in the front horizontal baffle. They worked way too good for a 150 hp O-320 not pulling a load. It was added early on in 604'S life by the first owner who sprayed alfalfa with it ocassionally in Nebraska. Was all piper parts and installation drawing, I replaced it with a single Niagra to run great temps and drop 12 pounds.
Last edited by OLDCROWE; 12-10-2016 at 08:03 PM.
"Don't feed the hipsters"
For guys interested in the numbers the two Niagara 20003A coolers weigh 2.4# each.
The idea is to put air control into the outlet ducts. One of a zillion details yet to be addressed.
Installing instruments sure has changed in the 10 years since the last go-round!
Maybe Dr. Randy will correct me, but I thought one was limited to one Viagra at a time...
Ok, back to your beautiful bird: looking great! I really like your cleanliness in the installations. When you go to fix or change, it will make it much easier.
On the side note, have you considered some hard points on the wings for 'wolf control' additions?
I don't know where you've been me lad, but I see you won first Prize!
SB, make sure the wrappers are removed before u install those boxes
Stewart, I love seeing your progress and reading your updates! Thanks for sharing them!
The wrappers stay on till final install time. Don't wanna zap one.
How to turn a bad fitting composite boot cowl into something useful. We liked the molded windshield channel. Mike envisioned a way to keep it and morph a more conventional boot cowl to it. But wait, why would I ever want to do old man gymnastics and hang upside down in impossibly cramped space to access behind the panel? What about accessing the rudder pedal pivots (BCSC's control setup has the pedals hanging from a pivot tube above). Why not make removable panels on the sides? No permission required. One more advantage of the experimental category.
Last edited by stewartb; 01-18-2017 at 01:12 PM.
Fine Line never fails to impress. Nice looking and comfy!
Progress. The G3X Touch component shelf has been wired. Holy cow that's a bunch of wires!
Details matter. Pretty blue powder coating on engine baffles, air box, and assorted engine compartment parts.
I see the dog and the cat are captivated by your project
Firewall forward is almost finished. G3X Touch components are in place. Entering the home stretch.
Why do some photos post sideways even when they're correctly oriented when loaded?
Holy rat's nest, Batman! Seriously, the G3X Touch looks simple and elegant from the front but there's a whole lot going on behing the panel. I never considered the cost of coordinating and wiring the various boxes. Lesson learned!
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