Sometimes you buy all the right parts, tighten every nut to perfection, and even check the lifter bore clearances, but...

C10 cat, I hate it when I can't find a wrench...

"HEY!!!! There's that 7/16" wrench I was missing"

It's the small stuff that kills you!

I had a buddy who purchased 2 new engines from Innovation. Messing with them, he wanted to add nitrous, so he buys this beautiful "rack" of stainless tubes with gas lines and nitrous lines all perfectly bent add fuel and nitrous to each port and attached them to equally beautiful fittings into the intake runners. It was awesome......except.......he didn't tighten 2 of the rear nitrous fittings on one motor and the vibration made them come off during a hard pass, went super lean in two holes and poof!!! Mucho dinero down the toilet.

There's a time and a place for alcohol.

LOL

There's more than one horror story of brand new motors going toast due to the wrong $12 bypass valve.

I. Hilt my first two motors last winter. I'm still nervous and constantly find myself listening to very perceived weird noise...

God knows how many I have built and I still get a little nervous/anxious the first time I fire them, especially on the first dyno pull. And the day that the nervous/anxious feeling goes away is the day that I quit doing it. That nervous/anxious feeling is what keeps me on my toes and makes sure that I take my time and do it right.
Eddie

No matter how diligent you are, things do happen. We're human and so are the people who make the parts. My current boat engine I had 3 of the 5 bolts holding the oil pump bottom cover back out. Thankfully I noticed the oil pressure drop, so I backed off and was near the ramp. Idled in with 10 lbs pressure.

This was with a well known US made performance oil pump - a brand I've used many times with no issue. It had never been disassembled, so they were not tq'ed from the factory correctly. Must've been made on a Monday or Tuesday.

I've added one more thing to the list to double-check.

I'm in the middle of my 502 efi build right now. I've built several engines in the past and even worked in a engine machine shop for a few years. This build just seems to be fighting me every step of the way. I'm not going to lie, I always get a little nervous/excited when firing them up for the first time! I can't wait to hear that sweet music the first time I turn the key.(hopefully)

Classic Budweiser performance mod....then again these day's that could be just a Bud finish....