>The distance between a crank bearing or rod bearing is less than 2 thousandths on modern engines. A small amount of oil in that tiny space is all that keeps your engine from having metal on metal seizure.
The BMW S65 and S85 engines are prime examples of what happens when the wrong tolerances are chosen. I can't think of another engine family where rod bearings are considered a maintenance item.
I had cracked a cylinder/piston on the original LSA. I did not trust anyone to do the work so I did a lot of research and did it all myself. I appreciate someone asking because my friends and software dev co workers aren't interested :)
I love working on cars so I totally get wanting to do that, but why didn't you trust someone else to do the work? There are probably more reputable LS builders across the US than any other engine family.
As cool as 2-atom thick plasma transfer wire arc cylinder liners are, that's not something which will ever be available to a layman.
And no, the LS motors have been in use since '97. Including the gen1/2 small blocks doesn't count, there are no shared parts between them.
Edit - For reference here's a video of the shop I'm referring to. They're far from a podunk operation. https://www.youtube.com/watch?v=8HgwF5dISmU
Edit: I dont have the machines they do, but when my bare block comes back from the machine shop, my tools are just as good as theirs to verify the dimensions are correct. That isn't possible to verify with a built short or long block. They could possibly have 100 employees that care as much about my job as me who knows. This is a job about verification of specs and assembling correctly not of insane tech. They don't have anything I dont when assembling an engine. Machine work yes
My wife's engine had an issue and it was the middle of winter so I said whatever let's just have a shop fix it. In the process they "flushed the transmission" and it failed 4 days after we got the car back. Of course they stonewalled us and I can't prove they broke it. So I ordered a late model wreck transmission and replaced it and 3 years later still running strong.
But I then decided that I would never be in that position again where someone could tell me it wasn't their problem and get me aggravated. With this engine I built it from raw parts. I had the block machined, and I had the tools to verify.
It was certainly not worth my time, but as you said I love working on cars too.
Flushing can really be bad if you've never done a routine flush on a schedule. You don't want to go 150,000 miles before your first one. You would need a garage with a forced flush system to move it all out, and then probably flush again soon after to make sure all the gunk is out.
Transmission oil breaks down with heat and wear like any other, and will eventually contain sludge and dirt.
Since a short block is mostly just a short block, I'll be interested in seeing if LS heads/intake manifold/headers takes off in the SBC community.
If you mean "do the LSx heads drop onto a gen1/2 SBC", then no, not at all. only thing common between them is the cylinder spacing. The LS uses 4 bolts per cylinder like a ford, instead of 5 like the SBC, the firing order is different, the valve layout is different (ports are symmetric vs mirrored), etc.
There are small block Chevrolet blocks that accept LS heads (Bill Mitchell maybe?)
(note: I wasn't referring to box-stock LS heads on a box-stock SBC)
what amazes me is the cam lifts we're running these days. I'm running .646"/.649". In the 90s .500" was big for a street motor, and only full blown race motors were running whats normal now.
You don't really hear about those other engines much because their buyers understand that a race engine needs more maintenance than any other road car.
Also, not beating on the engine until oil has warmed up to temp will elongate the bearing lifespan quite a bit. I have a friend with E60 6mt S85 that has factory bearings at 110k mi and has perfect oil analysis results.
The S54 is also notorious for VANOS issues and cam drive failures. I had to replace the solenoid pack on mine but elected to not upgrade the drive while I was in there.
4AGE is 4cyl 11:1 compression producing 155hp with 7200rpm redline.
S85 is 10cyl 12:1 compression producing 500hp with 8250rpm redline.
I am curious if there is proof to this. I've always felt the same way. I know in the "old days" with iron pistons, if you you simply started up a cold motor and and drove it hard without a warm up period, the pistons would expand quicker than the block and would start to scour the walls and/or lock up.
But other than that, the only other "proof" I have is from people in high school that like clock work at 3:30 everyday, would smoke tires leaving the parking lot everyday. They seemed to go through motors every 6 months. I'm talking knocking bearings and lifters cracked in half. I've never gotten rough with anything I own until after a 20 minute "warm up" and all has been well (so far).