L31 daily driver rebuild

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BeXtreme

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With all that being said... there is nothing stopping someone from just slapping some random junk from Lowes on their aircraft and flying off into the sunset, except that it is illegal. It's just like there isn't anything stopping you from speeding, until you get caught by the police and get a ticket.
 

Orpedcrow

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Define "Better".
More gooder, Higher quality
What are you asking the machine shop to do, and how much are they charging?
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This was his quote for the works, he said he wouldn’t have an issue doing any combination of machine work I wanted either.

I’m not trying to get by with spending as little money as possible, I want my money to be used efficiently.
 

Hipster

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One thing on aftermarket rotating kits, seldom do they not need any machine work at all. Small ends usually need honed/fitted if floating, cranks are generally a touch undersize and clearances can end up just shy out wore out. I like to start at the low side of clearance specs for a street engine instead of race spec/loose. Stuff is going to need to be checked and corrected if necessary. I wouldn't spend money for a balanced kit, I would have it done "my guy" when I have everything including the balancer and flexplate.

Skip has been known to be a bottom feeder as mentioned, 2 brothers using the same name, I've heard, but maybe the same guy trying to get away from his reputation with some CYA. Eagle most certainly had an issue(still do?) with their cranks breaking and there are no name cranks coming out of China as well.
 
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BeXtreme

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I know all about the FAA. This is where I work and have built almost every part of it for 330 of them
Man, I really like the Kodiaks. You've got a bunch of our stuff in there. I'm with the cert group at Garmin here in Salem. I don't do a whole lot with the GIFD stuff(we do mostly the retrofit avionics here), but I did some work looking at your planes when we were looking at supporting the Kodiak 100 on the GTX 3X5 AML STC for the ADS-B mandate a few years back.
 

Schurkey

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More gooder, Higher quality
What if SOME of the part is higher quality, and other facets of that part are lower quality?

If you want EVERYTHING better, you're not buying a "budget" part, and exceedingly little will come from China/Asia.

You might--or might not--get better steel in an aftermarket part...but crappy machining. You might get Famous Name Bragging Rights, and discover the part has hidden flaws that make it less-durable than OEM.

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You are almost guaranteed to need the block decked, ESPECIALLY if the pistons have been "destroked" as is common for replacement pistons. The block decks will not be square to the crankshaft, they vary from front to back, and one deck to the other. Typical SBC has the pistons approximately .025--.030 in the hole. Any head gasket thicker than the old-style steel shims at .015--.020 will have TOO MUCH squish/quench clearance. And this is made worse by "destroked" pistons that aren't made to the proper compression height. You can count on needing the decks cut to square them to the crank, and to remove excess quench clearance. So you need to specify your desired squish/quench distance to assure he takes ENOUGH off the deck surfaces once he finds out how far "in the hole" the pistons sit, how thick the head gasket is, and how goofy the decks were made to begin with. (Typically, the decks clean up flat and true with a shallow cut that won't get you to proper squish/quench distance. Some folks go as tight as .027-ish, I'd be satisfied at .035--.040 squish. Which probably means taking AT LEAST .020 off the decks.)

Honing with torque plates is strongly recommended. Ideally, using the same part number head gasket under the torque plate that you plan to use with the engine build.

My machine shop will CHECK the rods, resizing them only if needed. Of course, if you're using hot-rod replacement rod bolts, the rods will have to be resized. In which case, you need to know if you're going to TORQUE the new rod bolts, or STRETCH the new rod bolts...because the resizing has to be done after the bolts are tightened the same way you plan to tighten them.

WHICH piston is he proposing? "I" would insist on the flat-tops from the TBI Caprice/LT1. You'll gain a little compression, and they're dirt-cheap. They're "destroked" 0.010. Buy the right BRAND, and they come with coated skirts.
www.summitracing.com/parts/slp-h597dcp30

If you buy through your machinist, they'll cost more due to his profit margin.

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What are "chrome moly" rings??? I've seen chrome rings--garbage for performance use, but suitable for tractors and other farm equipment that sees a lot of dust. Hard on cylinder walls, takes significant break-in.

I've seen moly-faced rings. Wonderful for automotive use. "Broken-in" on the starter when you first crank the engine (Ok, that's slightly exaggerated...)

Chrome-moly is a grade of steel--4340, for example, otherwise known as "tool steel". Unlikely that piston rings would be tool steel.

Any oil-wetted engine surfaces that have been painted WILL NOT be used by me. Oil-wetted surfaces that aren't painted can't flake off and plug the oil pickup screen.

If you're using pushrod guideplates, you will HAVE to use hardened pushrods. Pushrods are the LAST thing you buy to complete a long-block, as there's a dozen variables that can affect the needed pushrod length.
 
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Erik the Awful

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Having been on the user end, and being in supply chain, I fully understand what FAA oversight can happen, but I also see what actually gets done. There's an awful lot of "self inspection", and there's a lot of crap parts and engineering because of it. *cough MCAS cough*
 
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