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Experience with FlyBoy Poor Man's Cold Air Induction System?

I do, but that's already in the listing!

Considering that the insulation sleeves help deflect heat away from the intake tubes, protect the rubber intake parts, and changed the injector balance on my engine (indicating that the idea works), the costs involved are chump change.

YMMV.

Will this system replace a true cold air sump? Of course not, but it does have a useful effect.
 
It has been stated in other threads that the improvements provided by a cold air sump (~7 HP) are primarily due to an increase in air volume (larger tubes), not temperature.
 
Experience with FlyBoy Poor Man's Cold Air Induction System

I installed this a few years ago. It was pretty easy and have had no problems with the components since installation. I can't say what or how much improvement because I wasn't careful enough to take any before/after measurements. I'd do it again, though.
 
Methinks there are several concepts being confabulated.

The original "cold air" intake was simply a bypass, a way to avoid routing the intake air through a bunch of cast intake tubes submerged in hot oil inside the 540 updraft sump. Rumored measurements claimed a reduction in delivered combustion air of a few degrees F. The same source found no evidence of sump heating with the plenum style horizontal sump intake, which doesn't run the air passages through the hot oil. (Yes, I know Lycoming now offers a cold air manifold for the 390 and rates it 5 hp higher. Go figure.)

The steel intake tubes between sump and heads also pick up heat. The actual energy gained would be fundamentally the same regardless of standard sump or cold air manifold. The big energy source is radiation from the adjacent exhaust head pipe. Wrapping the intake pipe should reduce delivered combustion air temperature if the wrap has a shiny reflective outer shell backed by an insulation layer. A chromed intake pipe would reject about 96% of the radiant heat, without the wrap.

We usually don't source combustion air from inside the lower cowl volume, except as an emergency alternate source, or for carb heat. When we do, the intake air is anywhere from 120F to 200F, so there is a significant loss of power.

Flyboy's "poor man's cold air" description is not unreasonable, as it would reduce radiant exhaust energy transfer to the intake tube walls.
 
I had my intake runners ceramic coated to keep the heat out. Only cost a $50 or so and they look great and no added "bulk".

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Off topic, but important:

At my current annual inspection, I found that one of my silicone spark plug leads (Taylor Spiro-Pro 8mm) had burned through to the core. it had been run nearby an exhaust pipe, similar to the routing you are using. All of the other wire leads that were run across the exhaust pipes had been discolored. There were no operational problems, but failure was likely. 130 hours. A cursory inspection did not show the burn-through, just discolorization. I had to bend the discolored areas slightly to find the problem.

I am replacing all of the affected leads (3 on my IO-540) and rerouting them.

Also I think Tom Swearengen (TS Flightlines) will have something to say about firesleeving on oil lines, but I will leave that to the experts.
 
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Off topic, but important:

At my current annual inspection, I found that one of my silicone spark plug leads (Taylor Spiro-Pro 8mm) had burned through to the core. it had been run nearby an exhaust pipe, similar to the routing you are using. All of the other wire leads that were run across the exhaust pipes had been discolored. There were no operational problems, but failure was likely. 130 hours. A cursory inspection did not show the burn-through, just discolorization. I had to bend the discolored areas slightly to find the problem.

I am replacing all of the affected leads (3 on my IO-540) and rerouting them.

Also I think Tom Swearingen (TS Flightlines) will have something to say about firesleeving on oil lines, but I will leave that to the experts.

Good catch on your plug wires! I have a 110hr now on my current setup and have zero signs of any heat problems, got to love ceramic coated exhaust.

In regards to fire sleeve. (note to self don't post pictures)
Inverted oil=lots of line=lots of an10 fire sleeve
Fire Sleeve= no visual inspection
FWF Fire=bad day with or with out fire sleeve
Tip open canopy with parachute=best chance of survival.
 
I'm just curious... if you're gonna wrap something, why not wrap or treat the exhaust? It will keep *everything* around cool, and retains the heat in the exhaust. That's supposed to be good for scavenging.
 
most people don't like to coat exhaust because of the "can't weld repair it" logic

i say coat it, if you get a crack, replace it
 
most people don't like to coat exhaust because of the "can't weld repair it" logic

i say coat it, if you get a crack, replace it

I was really worried about this also but its false. It really only applies if you have the pipe dipped and coated on the inside. This pic was just taken two days ago as I pulled my exhaust to weld on some bung fitting higher up. A simple wire brush took the ceramic coating right off and it welded up just fine. The pipe looks just as good with 110hr on it as it did with zero. I will gladly paid to have my pipes re-coated after the new smoke fittings are tested.

Just trying to post some real life experience with coated exhaust. lost of false info on here about it from people that don't have it.

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products

There are many "ceramic" products out there ranging from tapes to paints to baked coatings.

To generalize and say that you can remove the ceramic coating and weld normally is a stretch. That may be the case with your specific product but not the case with others.

What product did you use?
 
There are many "ceramic" products out there ranging from tapes to paints to baked coatings.

To generalize and say that you can remove the ceramic coating and weld normally is a stretch. That may be the case with your specific product but not the case with others.

What product did you use?

This is a great point. I embarrassingly don't remember what product I went with. I do know I had little to no choice as most products were only rated to 1200deg and the one I wanted and used was good to 2,000deg. For reference in my first pic the blue masking tape on pipe one accidentally got left there for the first engine start. After the initial 5min engine run I noticed the tape and it pealed right off and was not burned. I'm a fan!

Again just trying to add some real world experience here. Too many experts on VAF who post "the truth" about something when they have no personal experience with it.

My experience with coated exhaust:
Cheap
Cold CHT/Oil in Phoenix summer flying
Looks great
No burns on cowl or plug wires
Smoke works great (heat stays in pipe)
Heater works great (uncoated under heat exchange)
easily sanded off for welded repair

I have yet to see one person post "I wish I didn't coat my exhaust"
 
I wrapped mine last year. I did not see any change at all. Static rpm and wot rpms were unchanged.
 
I was under the impression that you do not want ceramic coated exhaust systems in aircraft because it is an important part of heat dissipation (you want the pipes to expel heat to the surrounding cooling air). Judging by experiences on this thread this looks to be not entirely important?
 
Concerning the "unknown" ceramic product - I was also wary of using the good looking automotive stuff as it only goes to 1200, so I went with a rough, black 2000 degree product from Jet Hot. Worked great on the mild steel 4-1 header I built for my Hiperbipe. Repair and rewelding was no particular issue for me.
 
I'm just curious... if you're gonna wrap something, why not wrap or treat the exhaust? It will keep *everything* around cool, and retains the heat in the exhaust. That's supposed to be good for scavenging.

I guess that the exhaust pipes also have a temperature limit and should be cooled by the air flow. If you wrap the exhaust pipes they could get out of that limit.
 
I guess that the exhaust pipes also have a temperature limit and should be cooled by the air flow. If you wrap the exhaust pipes they could get out of that limit.

For mild steel, maybe. Concerning Stainless (According to the internet):

HIGH TEMPERATURE PROPERTIES. Stainless steels have good strength and good resistance to corrosion and oxidation at elevated temperatures. Stainless steels are used at temperatures up to 1700? F for 304 and 316 and up to 2000 F for the high temperature stainless grade 309(S) and up to 2100? F for 310(S).

A Lycoming is not going to operate anywhere near 1700, so even with 100% effective insulation the pipes will remain well within their comfort zone.

That said, some here have experienced failures with wrapped/coated exhaust and some of us have no issues. So who knows?
 
A Lycoming is not going to operate anywhere near 1700, so even with 100% effective insulation the pipes will remain well within their comfort zone.

That said, some here have experienced failures with wrapped/coated exhaust and some of us have no issues. So who knows?

Typical EGT's can easily reach 1400-1500 2" down the pipe where the probe is located, so easy to imagine we're getting pretty close to 1700.
 
Typical EGT's can easily reach 1400-1500 2" down the pipe where the probe is located, so easy to imagine we're getting pretty close to 1700.

Well, even 1700 is still acceptable. Fortunately we don't need to use our imagination - there are plenty of people who have been flying with fully wrapped pipes for years and can tell us what their EGT is. I flew with ceramic and didnt notice an appreciable EGT difference with/without. And my Rocket exhaust is wrapped, though I have yet to fly. If nobody else chimes in with real data I'll be happy to report back with my observations.
 
most people don't like to coat exhaust because of the "can't weld repair it" logic

i say coat it, if you get a crack, replace it

Not sure if that is the case. My exhaust on the pervious RV7 was ceramic coated and had a crack on #1 pipe. I called Vertterman to inquire and possibly buy a new section which they told me they knew about this area and they would fix it for free. They simply welded it with no issues.
 
Interesting. Vetterman specifically told me he wouldn?t weld a ceramic coated pipe and that coating the pipe would void his warranty.
As others have said probably depends on the ceramic coating. Don?t think the stuff in a can from Home Depot would be a problem. A true baked on industrial ceramic coating could be very problematic.
 
Interesting. Vetterman specifically told me he wouldn?t weld a ceramic coated pipe and that coating the pipe would void his warranty.
As others have said probably depends on the ceramic coating. Don?t think the stuff in a can from Home Depot would be a problem. A true baked on industrial ceramic coating could be very problematic.

Mine was certainly not a Home Depot can stuff, didn't know that there is such a thing :)

Last one worked out great and they did not mentioned of any issues welding it. The cracking at that spot was known to them hence fixing it for free.
 
Welding difficulty is gettin' far from Flyboy intake wraps...I'm just sayin' ;)
 
Welding difficulty is gettin' far from Flyboy intake wraps...I'm just sayin' ;)

Disagree. Coatings are safer than wraps since they can't absorb oil, and the drawbacks to coatings are relevant to the discussion.
 
Coating discussion tends toward unsupported temperature claims.

Let's quantify.

Anyone have actual values (emissivity, absorptivity, reflectivity, transmissivity, etc) for any of these coatings?

Fair is fair. Vince, what do you have for the wrap?
 
Coating discussion tends toward unsupported temperature claims.

Let's quantify.

Anyone have actual values (emissivity, absorptivity, reflectivity, transmissivity, etc) for any of these coatings?

Fair is fair. Vince, what do you have for the wrap?


Certainly a fair question but anyone who has run either wrap or ceramic can attest to a significant to radical reduction in transmitted temps. Often the measurement is as crude as the accidental "flesh test". Aside from the debate about longevity, the heat certainly stays in the pipes until expelled out the back.

The benefit is there - but yes, measurement is absolutely needed to quantify.
 
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