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Superior XP-400 Service Bulletin

Titan 370 crankshafts

Continental Motors manufactures the crankshaft for the 370 cubic inch displacement engines. The displacement is 370, not 371, just 370. There are two variants: non-counterweighted or, for the high compression engines, forged with counterweight blades and equipped with counterweights. The high compression 370 engines also have oil squirts to the underside of the pistons to aid in cooling them. The counterweights are there to mitigate the harmonic frequency of the engine at certain power settings that could have adverse effect on metal propellers.
We plug the 370 crankshaft for either fixed pitch and constant speed props. depending on the customer requirement. They have been in service since 2011 without any problems.
 
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Superior doing the right thing

I also received a call today from Scott Hayes (VP of Sales and Marketing at Superior Airparts). It's an unfortunate situation but I think they are doing the right thing here. It's a rarity in today's environment to see a company put people ahead of profit. They are in a tough situation but their actions speak volumes about their integrity.
 
How is the buy-back structured financially? Is it pro-rated for hours of use?

BTW I'll add that I'm very happy to see Superior doing this... It's just the right thing to do.
 
Call your insurance company - Ground-Not in Motion

I just called Gallagher and changed my insurance policy to Ground-Not in Motion until I am back in the air. Save a few bucks for beer money to help drown your sorrows!
 
How is the buy-back structured financially? Is it pro-rated for hours of use?

BTW I'll add that I'm very happy to see Superior doing this... It's just the right thing to do.

The standard buy back structure includes Superior writing a check to the owners for the full value of the original purchase price (i.e., not pro-rated) in exchange for the XP-400 and the owners signature on a release of liability letter.

The arrangement also covers some costs for labor associated with removal and re-installation of the replacement motor and Superior is covering shipment costs back to their facility.

As a guy affected by this, I want to say how impressed I've been with the way Superior has handled this difficult situation. I've had numerous discussions with folks on the management team and as much as anyone hates to be faced with downtime, their responsiveness and willingness to help with individual circumstances to ease the pain has been remarkable and I want to acknowledge and thank them for that.

On a going forward basis, I also wanted to mention the option I've chosen that may be of interest to others. Barrett has been in contact with Superior and they've developed a plan to help get folks back in the air using the XP-400 as a "core" to salvage things such as cases, accessories, cams, etc. Cranks and cylinder assemblies will be from the Lycoming IO-390. This will help minimize financial impacts and hopefully help with lead times. Barrett would also be able to build angle valve OI-360s or 361s using this approach.

Not surprisingly, parts availability and lead times will quickly become an issue so if interested, best to pursue this option sooner rather than later.
 
Doesn't the IO-390 have larger mains than the Superior 400? Wouldn't this preclude re-using the XP cases?

Also seems like IO-390s and parts are way backlogged at Lycoming. I can't imagine there are lots of used parts floating around.
 
Doesn't the IO-390 have larger mains than the Superior 400? Wouldn't this preclude re-using the XP cases?

Also seems like IO-390s and parts are way backlogged at Lycoming. I can't imagine there are lots of used parts floating around.

Early 390's (all the kit engines like mine, IIRC) used a 2-3/8 crank, same as 360's. Only late model 390's have larger 2-5/8 mains. Not sure, but I think Lycoming made the change when they decided to certify. To recycle an XP-400, the key parts are a 360 pendulum crank and 390 big bore cylinders.

Availability will require Lycoming's cooperation, but the those cranks and cylinders should be available. Superior is being very cooperative about recycling the good 400 components.
 
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Sounds like Superior is doing everything possible to mitigate the inconvenience of this SB. Full credit for purchase price and no pro-rating for engine time as well as credit for R&I. That's about as good as it can get. On the bright side, figuring a conservative $10/hr reserve on these engines, then a 500 hr engine would have saved 5K.
Hope all you guys get back in the air soon.
 
The standard buy back structure includes Superior writing a check to the owners for the full value of the original purchase price (i.e., not pro-rated) in exchange for the XP-400 and the owners signature on a release of liability letter.

The arrangement also covers some costs for labor associated with removal and re-installation of the replacement motor and Superior is covering shipment costs back to their facility.

As a guy affected by this, I want to say how impressed I've been with the way Superior has handled this difficult situation. I've had numerous discussions with folks on the management team and as much as anyone hates to be faced with downtime, their responsiveness and willingness to help with individual circumstances to ease the pain has been remarkable and I want to acknowledge and thank them for that.

On a going forward basis, I also wanted to mention the option I've chosen that may be of interest to others. Barrett has been in contact with Superior and they've developed a plan to help get folks back in the air using the XP-400 as a "core" to salvage things such as cases, accessories, cams, etc. Cranks and cylinder assemblies will be from the Lycoming IO-390. This will help minimize financial impacts and hopefully help with lead times. Barrett would also be able to build angle valve OI-360s or 361s using this approach.

Not surprisingly, parts availability and lead times will quickly become an issue so if interested, best to pursue this option sooner rather than later.

Wow - very impressive response to a very difficult situation. Thanks for sharing this info. I'm so glad to hear customers are being treated well.

My best wishes go out to all who are affected. Yeah, it's a bummer to have to do an engine change, and maybe wait in line to get a new engine, but still way better than the alternative of a catastrophic engine failure. Other vendors should use this situation as the gold standard of service.
 
Kudos to Superior for the incredible way they are handling this issue! Any guess as to how many engines are being bought back?

Phil
 
Interesting article from a Sun 'n Fun podcast with Superior?s VP of Sales and Marketing, Scott Hayes:

http://flash.avweb.com/avwebflash/n...ck-of-XP-400-and-XP-382-Engines-232603-1.html

Interesting but I don't buy the detonation angle since there were failures even with only 20 degrees of advance. IO-390 Lycs aren't breaking cranks even with EIs installed.

Many IEs only advance timing at lower MAP where cylinder pressure is lower anyway.

I'd like to see data on what ignition systems the broken 400s were running. Any mags in that group of engines?
 
The biggest difference is the bore and stroke...

Bore Stroke

Lyc. 390 5.139 X 4.375

Superior 400 5.250 X 4.625

Not the same crankshaft at all...
 
Interesting article from a Sun 'n Fun podcast with Superior’s VP of Sales and Marketing, Scott Hayes:

http://flash.avweb.com/avwebflash/n...ck-of-XP-400-and-XP-382-Engines-232603-1.html
Interesting detonation causes crank failure. I always thought detonation would destroy the piston first. I have first hand experience. What is the compression ratio? I see they had 8.5:1 standard; 7.2:1 low, and 9:1 (8.9:1) available. 9:1 is too much. You will not have detonation issues at 7.2:1, and will have good margins with 8.5:1. That is why I have a stock O-360-A1A (8.5:1).

Lycoming played around with high CR for years, one example O-235. They had the standard version, 115HP (typical in C-152, Tomahawk, Grumman Yankee). They did make for a time a 125HP high compression engine for a time, but discontinued it, due to detonation. Years later the Grumman Yankee folks came up with STC to put the Lycoming high compression pistons back in. I test flew flight hours off for one of the STC's. I had detonation destroy one of the pistons. I had to make a quick landing at a grass strip with partial power, plane shaking like crazy. There was no indication of issue as the plane was fully instrumented. It just went. The O-235 came in 100HP, 115HP (L2C) or 118HP typically. 6.75:1, 8.1:1 and 8.5:1 were typical compression ratios. The higher compression was 9.7:1, and made 125HP (F2A). Anything over 8.5:1 is too much in a Lyc 4 banger (in my opinion).

That is why I have a stock O-360-A1A (8.5:1). That is a sweet spot. Anything more reduces your detonation margins. I know it can be done with the right fuel, timing, mixture... however reliability is far more important to me than a few HP.

Final report on XP-400 accident with (N838RV) from a crank failure. The report says 215HP. I assume CR was 8.9:1. The report says:
crankshaft had fractured forward of the No. 2 connecting rod journal. Further testing of the crankshaft revealed that the fracture was the result of fatigue cracking. There were no chemical variations or foreign material present in the metallurgical testing. The crankshaft only had 20 hours total time in service, suggesting that initiation of the cracking and the subsequent failure of the crankshaft was almost immediate.

http://www.vansairforce.com/community/showthread.php?t=166173
 
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Bore and Stroke

The biggest difference is the bore and stroke...

Bore Stroke

Lyc. 390 5.139 X 4.375

Superior 400 5.250 X 4.625

Not the same crankshaft at all...

Typo: The 390 has a bore of 5.319 ( 5-5/16? )
I?ve been waiting for someone to manufacture a set of parallel valve heads with this bore. I know of one set that was prototyped and showed promising results. No substitute for cubic inches ! :)
 
SO, Superior is buying the XP-400 back, but what are they offering that is equivalent in performance? I am looking at a newly built RV that had not flown yet. The owner is sending back the 400 and Superior is supposedly sending back a different engine. The owner is not sure what he is going to receive.

Anyone else doing an exchange?
 
I'm not doing an exchange with Superior, instead I had them ship my XP-400 to Barrett to rebuild it into an IO-390.

I removed the (never flown) engine and hauled it to Superior, about 30 minutes away. Scott gave me a tour of the facility. It's a pretty impressive shop and Scott was very friendly. Superior shipped the engine to BPE and they will tear it down and send the cylinders, crank, etc back to Superior for destruction. What's left (case, sump,...) will give life to an IO-390. The baffles, cables, hoses and wiring *should* reconnect to the new engine without major hassles.

I'm about 1 to 2 weeks from tear down at BPE. Unfortunately, the next batch of cylinders from Lycoming won't arrive until July. I'm probably not in that batch but a subsequent one. It's going to be a long wait... In the meantime I'm still waiting on 'the' check from Superior. They are waiting for the tear down to confirm serial numbers. I dropped off my engine on 3/18.
 
Interesting. I guess I need to talk to the owner of the plane I am looking at. It is a RV-14 and should have the IO-390 in it. If the "exchange is any less than 210 HP I would not want it. In fact, I'm not sure I would want the Superior engine at all.
 
Rebuild from Superior to Lycoming

Any idea the wait time to get a Superior 400 to Lycoming 390 rebuild is ?
 
Now that the smoke has settled on the XP-400 buy-back program, does anyone have any parts left over. I am looking for a set of xp-400 cylinders. Maybe someone has some that didn't get returned. Any news would be appreciated.
 
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