Experimental Cessna 172 performance

AlphaPilotFlyer

Pre-takeoff checklist
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AlphaPilotFlyer
We finally got some better cameras worth posting some videos of our C172 with V8 engine flight testing. I tried to answer many of the questions I received from the forum while flying in the pattern. The youtube link is below, or just search 'cessna 172 corsair V8 engine'. Hope some find it interesting.

 
Glad to see some modern alternatives to the 1950’s designs that are still used. Hope it proves to be reliable for all involved as it really is stupid to have to prime an engine and adjust mixtures in this day and age.
 
Certainly looks promising. I hope you're able to get an STC for normal cat...
 
Love that build, really hope it's successful.
 
Interesting idea. What happens in 5 years if GM decides to stop making that particular engine? Support and parts in 20, 30 years?
 
Interesting idea. What happens in 5 years if GM decides to stop making that particular engine? Support and parts in 20, 30 years?
Assuming it's the LS-series they're using, there are literally hundreds of thousands of those engines produced. They are manufactured by GM, but there are plenty of aftermarket producers as well (Dart racing blocks for example). The LS block will probably be more plentiful than the GM SBC 350 which can still be found locally or bought/built from new. If there's one thing I wouldn't be worried about for the next 50 years, it's LS engine components.
 
Interesting idea. What happens in 5 years if GM decides to stop making that particular engine? Support and parts in 20, 30 years?

The original SBC was introduced in 1954 and you can still get brand new parts for them. Getting parts for an LSx engine is even easier. That's most definitely a non-issue for this engine family.
 
Didn’t know it was that long lived. A big plus. What would have to happen to certify it I wonder?
 
We use a marine version the LS block, then modify it for the aircraft mission. GM says they plan on producing it for an extended time, whatever that means. There are similar newer blocks that will also work.

Thanks for the comments.
 
Glad to see some modern alternatives to the 1950’s designs that are still used. Hope it proves to be reliable for all involved as it really is stupid to have to prime an engine and adjust mixtures in this day and age.
It's a disgusting travesty. Lyco/Conti build expensive 1920's trash
 
You should do this for 182s
Sounds like it would be a simple chip change to boost the HP up to what a 182 needs. This would be a very slick business model. One engine, many HP possibilities and many application possibilities by just changing the ECU chip/programming to select how much HP is "de rated".
 
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Didn’t know it was that long lived. A big plus. What would have to happen to certify it I wonder?

It's a running joke in the auto world that any time someone needs/wants to put a new engine in a vehicle you ask them "are you gonna LS-swap it?". It's probably the most swapped engine in the past two decades because it's simple/reliable, lightweight, and makes great power. People put them in everything from jeeps and muscle cars to Mazda Miatas. I have my own dislike of certain LS-variants, but it's mainly due to EPA garbage (namely GM's active fuel management where it shuts down half of the cylinders). However, the version that they are using in the 172 doesn't have that AFM equipment.
 
Interesting idea. What happens in 5 years if GM decides to stop making that particular engine? Support and parts in 20, 30 years?

My info may be out of date, but as late as 2010 you could still buy every part for every GM car back to 1955.
 
How many laps around that pattern have you done as part of your engine testing regimen? You look like you've done it a few million times.

Good luck with the engine. Its great to get a modern choice out there.
How do the engine and components compare weight-wise to a Lycoming 0-320?
 
That's pretty neat. I wish you much success. Sure would like to see it in person. I would like to know how you did the engine mounts. Tube structure mated to the GM engine mounts? or did you come up with a better idea.
 
I love the idea, but I don’t think the weight would work in an RV-9A.
It would certainly kill my useful load.
 
That's pretty neat. I wish you much success. Sure would like to see it in person. I would like to know how you did the engine mounts. Tube structure mated to the GM engine mounts? or did you come up with a better idea.

Chromoly tube cradle engine mount using same 4 firewall bolts as original.
 
Is it indeed as simple as changing the chip to provide different HP output, different applications?
 
Didn’t know it was that long lived. A big plus. What would have to happen to certify it I wonder?
Suitcases full of cash and several years of dealing with the FAA
 
Foreign registered airplanes can fly in the US. Why not register your plane in Panama like all of the cruise ships, container ships, and oil tankers ? The Panamanian rules "might" be more lenient. :D


(yes, I'm kidding......)
 
It's been done in the past, but pilot would need Panama pilot certificate, medical and mechanic .... New faa LSA rules would make it easily work.
 
It's been done in the past, but pilot would need Panama pilot certificate, medical and mechanic .... New faa LSA rules would make it easily work.
Doable - The nice people of Panama could just give you a Panamanian license and other credentials if you had a US equivalent - for a fee. That J.G. Wentworth guy could run the operation - I'm sure he's legit......
 
Is it indeed as simple as changing the chip to provide different HP output, different applications?

Well ... back in the day we'd just add a B&M 6-71 on top: :dunno:

hrdp_0905_14_z-supercharged_chevrolet_LS_engine-.jpg
 
It's a disgusting travesty. Lyco/Conti build expensive 1920's trash


There aren't plenty of examples that are far worse in automotive tech produced by top shelf brands...

We have a C50 Chevy grain truck powered by a 350 that has eaten three different engines in 80k miles. Every one of them has thrown a rod. The first engine was brand new when grandpa bought the truck, threw a rod at 40k miles. The second engine was a crate GM Goodwrench replacement, threw a rod about 30k miles later. And the same story on the latest. Pretty much half or more of those miles this truck was EMPTY.

I posted questions about this truck and engine on a farmer's forum asking what gives and they all had similar stories, its just the nature of them. One poster replied that he was a shipping delivery guy in the 80s & 90s and he was always bringing new 350s to all the old auto shops that dotted the midwestern farm towns, because they don't last...

6 liter Power Stroke. Northstars. Triton.

There is plenty of trash in automotive industry.
 
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Also, isn't it true that aircraft engines are a lot more reliable than they were in the 1920s?
 
And what about the engines you build?
That's Raptor logic, no? But the post was mostly hyperbolic anyway. My disdain for mixture tinkering and all the theatrics that go along with operating these engines is well known, I'm generally "over it" at this point but couldn't pass up this opportunity for a gratuitous "engines suck". I wish these guys luck

There aren't plenty of examples that are far worse in automotive tech produced by top shelf brands
For sure. And same in marine world. Some outboards tolerate decades of salt water abuse with no real maintenance.. others not so much!

Also, isn't it true that aircraft engines are a lot more reliable than they were in the 1920s?
I've often wondered this.. any data? And if they are more reliable now is that due to a better understanding and operating habits by pilots or something else?
 
I've often wondered this.. any data? And if they are more reliable now is that due to a better understanding and operating habits by pilots or something else?
It appears that my Googling skills are not up to that task!
 
I've often wondered this.. any data? And if they are more reliable now is that due to a better understanding and operating habits by pilots or something else?
Yes, there is a higher "reliability" with engines today vs in the past but you don't need to go back to the 20s. It's mainly due to the manufacturing process has modernized and removed a lot of procedural root causes of previous failures. I haven't spent much time on the recip side but it's been documented on the turbine side. In addition to the mfg process upgrades the increase use and refinement of NDT technologies allowed less flawed engines/components from entering the food chain in the first place. And while we still see ADs against crankshafts or turbine wheel that are mfg'd based on 60+ year old designs, the issue usually falls to someone thinking they "improve" on how things are done vs following the tried and true "old" method. The FAA had a couple studies out years ago on this but not in place to look for them at present time.
 
It appears that my Googling skills are not up to that task!
Nor are mine :( the recent Paul AvWeb video was pretty good. It does appear that there isn't much data on this unfortunately though
 
It appears that my Googling skills are not up to that task!
It does appear that there isn't much data on this unfortunately though
Perhaps search for discussions on the single engine vs twin engine debate and on ETOPS. I seem to recall various engine failure statistics being used to discuss these topics. I had read a report by a top shelf oil company that switched back to single turbine helicopters based on their own research of failures. If I recall correctly they mentioned the mfg process angle which was similar to the FAA and other reports I've seen. Maybe search google scholar for engine reliability studies??
 
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