I don't understand why you would want compound turbos at all in an airplane application? I'd want one turbo sized for peak efficiency. I'd settle for parallel twins only if the packaging benefits were very compelling.

Why did he add aileron spades before the first flight?

Same reason the TSIO-550C has two turbos and two intercoolers.

Works good, lasts long time, because it has a balanced air charge and balanced cooling from the air passing in the left and right side of the cooling intlets at the front of the cowling.

If you're going to run two turbos that don't share the same cooling path and mechanism, you're right, your best bet is to run one large turbo but he probably doesn't have the space for an appropriately-sized turbo. That's why in Audi/VW/Mits applications we run one smaller turbo where it's hotter and one slightly larger turbo with better cooling. 2 turbos are what many of these types of engines were designed to work with.

The issue is in a vehicle application, there is a huge area for the intercoolers to pick up nice cold air and a low pressure discharge area where the air flow can't bottleneck and back up and goes unimpeded through the IC's. Additionally in a vehicle you get spurts of high turbo demand then back off. In a racing application less so but it still spools and unspools both turbos.

In this application he's got the turbos both putting out 90%+ at all times. The cooling required to do that may exceed the ability of those IC's in those areas without better air flow. It's just one of many areas that needs an expert in air flow dynamics which I certainly am not, I just build these kinds of engines for street / strip us (or rather used to about 7 years ago as a hobby).

I'm guessing that was to balance the ailerons. Probably didn't have enough lower edge to apply weights there like almost everyone else does.

Then again, maybe he thought the spades looked cool.

He's got all these cooling issues and clearly isn't getting 400hp from the motor. But consider that his ineptitude to resolve those issues may be keeping him alive. I'm concerned he could resolve enough powerplant problems to get back in the air.

I was blown away at his latest video. I really expected the next video would be him giving up. Man this guy is committed. Haha

I dont mind the chicken wire fix for intake. He just needs to make the mods, they do not need to be pretty. I am more worried why it was the way it was. How did that get missed?

Are you guys saying he has two turbos in series? and they are the same size? why the hell would you do that? thats the worst case scenario for building heat. Maybe instead of trying to get rid of so much heat he should not make all the heat in the first place.

I wonder what his after IC intake temps are? He really needs to get a pro to help with engine tune. I bet a guy that knows what he is looking at would find the issues right away. Peter does not know what he does not know. I have done a fair amount of tuning myself and have missed some things that my experienced buddy looks at and sees in seconds. And I have tuned a lot more engines than Peter has.

Mike

There is no way this guy is giving up. It's not in him. He's going to be in it to the bitter end.

I agree WRT the fix; it doesn't have to be pretty. He's not trying to make a production worthy solution, he's just engineering on the fly and putting out fires with flashes of inspiration.

If I remember correctly, he said that the reason that he had the scoop in the down position / "closed" position was because it forced the air through the radiators rather than going over the top (because there was no back wall). Now that he thinks the solution is airflow, he has to make sure that it's still going somewhere useful.

That was my understanding too, but it seems like the lazy answer -- he was worried about cooling, but didn't think he should open his scoop because he hadn't built a back wall.

I was skeptical of his tufting demonstration -- that the tufts were getting pulled into the scoop at full power could have just been the engine intake air and not airflow from the prop over the radiators.

I had to go back and look. He has a Garrett 2867 into 2871. He had calculated 6 psi boost out of the small one and 21 psi out of the big one.

Edit:

Oh he took an online webinar on tuning, so he’s good.

I don’t get why you would need a small turbo for aircraft. The only benefit of the small turbo over the larger ones is response. Why do you need throttle response in a plane? Turbo props have slow throttle response and they seem to work fine.

I will admit I am a supercharger guy not a turbo guy. I don’t see any reason to have two inline. I get twin turbos, one for each side, but two on one exhaust seems to be a mess.


Mike

His reasoning was to get the hp he wanted at FL25 with the corrected airflow and boost, he needed staged turbos. In series, you will have 2 stages of compression to get the higher boost. A lot of guys are saying these aren't the correct turbos for the application. I'm no turbo guy.

Had to chuckle at the FL250 comment. Let’s see pattern altitude first.

LOL, notice I said "His" reasoning

He better have a 20 gallon tank up front for coolant. I think he may have 60 more seconds with that extra 5 gallons.

What level of manifold pressure would he need for this diesel to make full / cruise power? There are already piston aircraft making good MPs in the flight levels.

What level of manifold pressure would he need for this diesel to make full / cruise power? There are already piston aircraft making good MPs in the flight levels.