Cardinal RG mods

hindsight2020

hindsight2020

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hindsight2020
Did a search, very little info. Anybody flown the TN Cardinal RG mod? How does it perform on climb and cruise? I hear the mod is like 40K out the door, and again doesn't seem to be very much at all posted online on performance specs. Does the modification even come with modified performance figures? Does the useful load get outright crushed with all the extra weight of the turbo normalizing kit?

Anybody heard of the cowlabunga mod (or some sort of name like that). I've always been skeptical of speed mods, based on my own experience with full K2U modded Arrow, that does not do anything more than like 3knots over stock in real world (aka imperfect airplane) conditions. Something like 30AMUS installed? People have suggested it adds like 15 knots, which I reject at face value unless it comes with full panel picture/video proof (life advice which oddly applies to online dating as well...ask me how I know :D).

Watching my aging parents struggle with mobility this holiday season while I continue to sit on my @ss about taking them flying back home in the island, has galvanized my desire for a ingress/friendly and width comfortable airplane. I took them on a 172 18 years ago when they were much more agile, and I'd like to do that more often before time runs out. I have a bunch of time in cardinal rentals back in college and though I never did pay attention to its ergonomics back then, it really resonates with me how comfortable it is for a low power piston. Its stock performance is just underwhelming (aka Arrow equivalent) unfortunately.
 
Owned a Cardinal RG for a while. You're only going to get so much out out the same 200hp Lycoming the Arrow used. I did plan on 140 knots at a tick under 10 gal/hr with a 1006 lb useful load - which doesn't exactly suck.

Because it has a stabilator it trims out faster if you load it towards the aft end of the CG limit. Notice I said towards (in case anyone thinks I'm suggesting anything hazardous). With the three blade prop it was damn near impossible to load it tail heavy but "do your own math" applies here.

As for the mod you mention, I've never heard of it. Sounds like a LoPresti name though. Anything that man touched was gold.

The design of the stock cowl is attrocious and was done when TLAR applied more than calculation and analysis. The main complaints were mostly about marginal cooling. Lots of room for improvement there but I'm skeptical you would see 15 kts out of any cowl mod.
 
How does the TN mod compared to the IO-390?
 
asicer said:
How does the TN mod compared to the IO-390?
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Good question, but 390 cylinders are out to lunch on the cost front. People suggest the engine certification standards are tighter than the 360 (the whole thing about the new engines being -0%/+(?)% tolerance, whereas the old ones could be putting out less than the advertised power by design), but I just don't see a piddly 10hp increase do more for the airplane than a turbonormalizing kit, which would allow you to maintain rated climb power to critical altitude. I just haven't heard any PIREPS from anyone who has owned or flown the TN mod, which is why I made the thread.

The main concern with that mod would be weight. Cardinals are already piggish on the useful, a TN kit would crush it unless they did something clever to keep weight down....
 
Aviation Consumer did a review several years ago. If you haven't seen it, you might want to check it out.
 
aftCG said:
Owned a Cardinal RG for a while. You're only going to get so much out out the same 200hp Lycoming the Arrow used. I did plan on 140 knots at a tick under 10 gal/hr with a 1006 lb useful load - which doesn't exactly suck.

Because it has a stabilator it trims out faster if you load it towards the aft end of the CG limit. Notice I said towards (in case anyone thinks I'm suggesting anything hazardous). With the three blade prop it was damn near impossible to load it tail heavy but "do your own math" applies here.

As for the mod you mention, I've never heard of it. Sounds like a LoPresti name though. Anything that man touched was gold.

The design of the stock cowl is attrocious and was done when TLAR applied more than calculation and analysis. The main complaints were mostly about marginal cooling. Lots of room for improvement there but I'm skeptical you would see 15 kts out of any cowl mod.
Click to expand...

My understanding is cardinal CG is nose heavy as it is, so a 3-blade would make things worse. Meaning, aft loaded profiles (aka liberal use of back seat and bag compartment) is actually preferred.
 
Can the older (late '60s) 177s be upgraded to the larger engines? Or is there an airframe issue (elevator authority, etc.)?
 
GRG55 said:
Can the older (late '60s) 177s be upgraded to the larger engines? Or is there an airframe issue (elevator authority, etc.)?
Click to expand...

I dunno, I read the TAT TN STC limited itself in scope to the RG, and nobody ever pursued big engine STCs, just like nobody ever pursued the same solution for the Arrow. I don't doubt the Cardinal is CG limited due to the placement of the wing in order to accommodate the aesthetics of the cantilever wing.
 
@PaulMillner has the turbo system for his RG and can likely share. My regular IO360 RG cruises at 140 KTAS. I believe the turbo system can reach 170 KTAS at altitude as sea level power is available to 20k ft., but it’s less of an assist at lower altitudes. I’ve heard the 390 engine is good for 150 KTAS with a 15hp increase (the 360, certified earlier, rounds up the hp to 200). Climb performance is better with these mods which may be a more important consideration. The cardinal wing is not a spritely climber.

I believe the lopresti cowl is no longer available. Perhaps only 1 exists? The other popular performance mod is a powerflow exhaust. Lots of info on CFO about all of the various mods available.
 
BrianNC said:
Video from Avweb. TAS at 17,000 feet was pretty nice.


Here's the Avweb article.

https://www.thefreelibrary.com/Turbonormalized+Cardinal:+an+honest+177+knots+on+11+GPH+turns+the...-a0199593501
Click to expand...
Yeah I've seen the video, I really wish they would have spoken about the useful load penalty. I suspect that's a data point they rather not highlight. By the 2kt per thousand rule, that means a true 150kt airplane at 12K on the same 8.5:1 engine and no turbo-supercharging, which is nice since you can lean, and the intercooler saves you fuel on cooling. 40 AMUs is steep, would be a good expenditure for a runout airplane bought at a discount.
 
hindsight2020 said:
I don't doubt the Cardinal is CG limited due to the placement of the wing in order to accommodate the aesthetics of the cantilever wing.
Click to expand...
I'd think CG would be a potential issue for any modification that would make a Cardinal more nose-heavy than it already is. As Hindsight mentioned, the wing is placed pretty far aft (for packaging as well as aesthetics -- to get the main spar carrythrough positioned behind the pilot's head). The original 177's forward CG limit is unusually far forward -- only 5% of mean aerodynamic chord (by comparison it's about 15% MAC on a C-172). Thus Cessna had to resort to using a stabilator on the Cardinal, to get enough pitch authority for a tail-low landing with full flap at forward CG.
 
kyleb said:
Doesn't the Aviation Consumer article mention a 35 lb penalty?
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Oh snap you're right. Thanks, I just Ctrl+F it. the google fu was weak on this one. That's really not that bad for the added cape.
 
Seems like a great way to end up with mid to creampuff C210 money in a Cardinal.

Personally, I'd buy a strutted 210 1963 or later any day, hell of a lot easier to fix the fuel tanks. The 1964 C210 has one of the highest service ceilings of any N/A single piston plane
 
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hindsight2020 said:
Did a search, very little info. Anybody flown the TN Cardinal RG mod? How does it perform on climb and cruise? I hear the mod is like 40K out the door, and again doesn't seem to be very much at all posted online on performance specs. Does the modification even come with modified performance figures? Does the useful load get outright crushed with all the extra weight of the turbo normalizing kit?

Anybody heard of the cowlabunga mod (or some sort of name like that).
Click to expand...

Hi Hindsight,

There are sixteen articles on the Cardinal turbo system posted on the Cardinal Flyers Online webpage, here's a link to the one on Performance:

http://www.cardinalflyers.com/tech/info/turboprf.php

In addition, there are over 3,000 messages (!) in our Virtual Digest system that mention the turbo system, so lots of reading there. All of that is behind the paywall, but if $34 is an obstacle, it may be that turbocharged aircraft might not be your cup of tea. :)

I've got a couple thousand hours in turbo Cardinals, originally the fixed gear, more recently the RG. The FG turbo is no longer supported. However, three folks have installed the FG system on field approval (technically, a one aircraft/engine STC, but no drawings required...) I was one of those three, and later upgraded to the RG turbo.

Weight depends on which version... if you look at Tornado Alley's website, you'll see there's a Cardinal Cruiser 1, 2 and 3 version... weight varies from 35 pounds to 40 pounds. However, Tornado Alley now has approval for the two-bladed Hartzell scimitar composite prop, which significantly offsets the weight gain, while shifting CG aft desirably.

ROP, Tornado Alley claims 177 knots at 17,700' cruise. The certified ceiling is 20,000'. Bootstrapping becomes noticeable in the 23,000' to 25,000' realm, depending on atmospheric conditions.

LOP, burning 10 to 11 GPH (as limited by CHTs in the summertime) I'll see 160 to 170 kts, depending on a wide variety of factors we all learned about in the private pilot curriculum.

You can add the IO390 with the turbo if you wish, the IO390 is on the Tornado Alley STC now.

LoPresti Speed Merchants was acquired, and they've discontinued support of most of their aerodynamic mods it seems. There were three or four Cowlabungas installed... most of the speed gain came from the mandatory PowerFlow exhaust installed with... PowerFlow is definitely a popular mod.

For the '68 Cardinals that were 150 HP, there are two 160 HP, and multiple 180 HP STCs, with and without CS props. A handful of FGs have had 200 horse engines installed on field approval, similar to the process noted above. Cooling is a challenge, but we now understand most of the workarounds to accomplish that... a lot of that Cardinal cooling work was done by/with Tornado Alley to improve the serviceability of the turbo mod, and achieve under 380 F CHTs (which didn't use to be a Lycoming criteria...)

Let me know if you have any other questions. Paul
 
I heard the best mod was the 210 :)
 
PaulMillner said:
Hi Hindsight,

There are sixteen articles on the Cardinal turbo system posted on the Cardinal Flyers Online webpage, here's a link to the one on Performance:

http://www.cardinalflyers.com/tech/info/turboprf.php

In addition, there are over 3,000 messages (!) in our Virtual Digest system that mention the turbo system, so lots of reading there. All of that is behind the paywall, but if $34 is an obstacle, it may be that turbocharged aircraft might not be your cup of tea. :)

I've got a couple thousand hours in turbo Cardinals, originally the fixed gear, more recently the RG. The FG turbo is no longer supported. However, three folks have installed the FG system on field approval (technically, a one aircraft/engine STC, but no drawings required...) I was one of those three, and later upgraded to the RG turbo.

Weight depends on which version... if you look at Tornado Alley's website, you'll see there's a Cardinal Cruiser 1, 2 and 3 version... weight varies from 35 pounds to 40 pounds. However, Tornado Alley now has approval for the two-bladed Hartzell scimitar composite prop, which significantly offsets the weight gain, while shifting CG aft desirably.

ROP, Tornado Alley claims 177 knots at 17,700' cruise. The certified ceiling is 20,000'. Bootstrapping becomes noticeable in the 23,000' to 25,000' realm, depending on atmospheric conditions.

LOP, burning 10 to 11 GPH (as limited by CHTs in the summertime) I'll see 160 to 170 kts, depending on a wide variety of factors we all learned about in the private pilot curriculum.

You can add the IO390 with the turbo if you wish, the IO390 is on the Tornado Alley STC now.

LoPresti Speed Merchants was acquired, and they've discontinued support of most of their aerodynamic mods it seems. There were three or four Cowlabungas installed... most of the speed gain came from the mandatory PowerFlow exhaust installed with... PowerFlow is definitely a popular mod.

For the '68 Cardinals that were 150 HP, there are two 160 HP, and multiple 180 HP STCs, with and without CS props. A handful of FGs have had 200 horse engines installed on field approval, similar to the process noted above. Cooling is a challenge, but we now understand most of the workarounds to accomplish that... a lot of that Cardinal cooling work was done by/with Tornado Alley to improve the serviceability of the turbo mod, and achieve under 380 F CHTs (which didn't use to be a Lycoming criteria...)

Let me know if you have any other questions. Paul
Click to expand...

Paul, thank you very much for the detailed response. I might join up CFO as I narrow down my more pressing mission needs. I got a soft spot for the cardinal RG, it was the airplane I got my complex endorsement in after all. It's normally not a lateral I would consider especially as an arrow owner already, but some things have changed in the home front and the ingress and pax comfort have reared its head again. On the Lycoming side of the house you can't beat the cardinal doors and cabin.

The io390 route underwhelms me based on the cylinder kit prices. I think a turbonormalization kit is a better bang for the buck if I were to sink that kind of money into a forever airplane.

Quick couple of questions:

What year did the RG cowling change? Any speed differences of consequence? Any cooling issues between the different years of the RG?

How are the climb rates in non o2 altitudes for you with the TN?

Regarding stock engines, you mentioned the power flow exhaust. Would you consider that a worthwhile mod? I always thought it a bit of snake oil, but if you're saying the gains are notable, then perhaps it would be a worthy mod if ones not willing to go full up and spring for a TN setup.

I did not know there were lighter 2 blades available for the cardinal. That's def worth looking into for the CG issue alone.
Thanks again for any and all feedback.
 
Mine doesn’t have turbo but my 74 RG trues at 165 mph and between 9 and 10 GPH between 5000’ and 9000’. The TAS remains pretty constant but fuel burn goes down slightly as altitude increases. Mine doesn’t have any mods.

The highest I’ve flown for any length of time is 14500 but it was still climbing at over 400 fpm with two on board and about 200 lbs under gross (we had a lot of luggage for a long trip).

I regularly carry Texas sized couples and some luggage with me. I can usually carry at least 4 hours of fuel and stay within all limits with three people on board (I’m 6’4” and 260 lbs).

With my wife and another couple I’m usually limited to 3 hours of fuel but we’ve never had a reason to take another couple on more than a short flight. If I were going to regularly want to fly with 4 people on board I’d move up to a 210.

I fly with Angel Flight and my passengers regularly comment on how easy it is to get in and out of the RG and how comfortable it is compared to other planes they fly in. Most have flown in a lot more different types of plane than I have so I defer to their judgment. I just know I like the Cardinal.

Gary
 
hindsight2020 said:
By the 2kt per thousand rule, that means a true 150kt airplane at 12K on the same 8.5:1 engine and no turbo-supercharging, which is nice since you can lean, and the intercooler saves you fuel on cooling. 40 AMUs is steep, would be a good expenditure for a runout airplane bought at a discount.
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Note that it's an 8.7:1 compression ratio engine on the IO360A series. And even with turbo-supercharging, you can lean one you set cruise power; in fact, the turbo Cardinal even at 32" MP (Cardinal Cruiser 3) accepts LOP quite nicely.

Paul
 
PaulMillner said:
Note that it's an 8.7:1 compression ratio engine on the IO360A series. And even with turbo-supercharging, you can lean one you set cruise power; in fact, the turbo Cardinal even at 32" MP (Cardinal Cruiser 3) accepts LOP quite nicely.

Paul
Click to expand...
I think you meant turbo-normalizing, but indeed sounds like a well done intercooling mod, if you are not having CHT/det problems leaning this turbo setup.

Do we have an idea of how many installations are out there for the TN mod on the 177rg? Was it a popular mod or are they hen's teeth? What would in your opinion be the best economic candidate for the modification? I assume that installation is probably north of 50K all in these days, hard to justify vice looking for one installed.

Do we know if the IO-390 situation has improved? Are cylinders still 4K a pop and no cylinder overhauls allowed? That's a big non-starter for me as an owner, versus just slapping a powerflow on a stock IO-360 and calling it a day.
 
PaulMillner said:
Note that it's an 8.7:1 compression ratio engine on the IO360A series. And even with turbo-supercharging, you can lean one you set cruise power; in fact, the turbo Cardinal even at 32" MP (Cardinal Cruiser 3) accepts LOP quite nicely.
Click to expand...

hindsight2020 said:
I think you meant turbo-normalizing
Click to expand...

Well, no; I meant what I said... even supercharged engines can lean in cruise; full rich is only required for full-power climbs.

hindsight2020 said:
It indeed sounds like a well-done intercooling mod, if you are not having CHT/detonation problems leaning this turbo setup.
Click to expand...

A lot of work has gone into making that so over the years.

hindsight2020 said:
Do we have an idea of how many installations are out there for the TN mod on the 177 RG?
Click to expand...

About 70-some I'd guess, of all three configurations: the original with inadequate fuel flow, the type two with reflowed fuel servo, and the latest configuration with intercooler and popoff valve, plus improved turbo and induction plumbing.

hindsight2020 said:
Was it a popular mod or are they hen's teeth?
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Very popular to most of us that have them; never have seen a hen's tooth, unless you're going back to chicken's dinosaur roots.

hindsight2020 said:
What would in your opinion be the best economic candidate for the modification?
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An aircraft that has the avionics, interior, and paint that you want. I always thought it made sense to modify a mid time to nearly run out engine, so that if you're going to make any beginner mistakes, you're not imperiling a new engine, but opinions vary.

hindsight2020 said:
I assume that installation is probably north of 50K all in these day.
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Why would you assume that? I thought you had the price from Tornado Alley... that's an all-in price.

hindsight2020 said:
...hard to justify versus looking for one installed.
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That is true of EVERY improvement mentioned above... avionics, paint, interior, engine. But you may not live long enough to find the airplane that's exactly as you want it. So, either settle, or modify.

hindsight2020 said:
Do we know if the IO390 situation has improved? Are cylinders still 4K a pop and no cylinder overhauls allowed?
Click to expand...

I don't think there's been any pressure on that pricing. Why would no cylinder overhauls be allowed? How could that be enforced?]

hindsight2020 said:
That's a big non-starter for me as an owner, versus just slapping a PowerFlow on a stock IO360 and calling it a day.
Click to expand...

You create a false dichotomy; the two alternatives are NOT just IO390, or PowerFlow on a 360.

Paul
 
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