[Nick M3]

Ha! Forgot to include a major pre-installation component of the story.

So. The engine. I was regasketing, rebuilding vanos, etc, because it sure is a lot nicer to do that on a stand than in the car. I also decided to do a leakdown test. Unfortunately, it failed leakdown.

It turned out that the valve seats got contaminated during storage. It's amazing how much air you lose to even the slightest contamination (see the black spots on the uncleaned valve). Some cylinders were as high as 30% leakdown. Which is not ideal. Fortunately, after cleaning the valves and lapping them in, everything went to the 1-2% range where it should be.

Bonus headers content in the last picture. It turns out that the stock US headers actually work really well when they aren't plugged up by cats right at the merge. Since you need to cut the headers up to fit them in an E30 properly, these are a really easy, cheap, great functioning option. (Especially cheap when you already have them.) Some aftermarket headers kind of fit, but they usually don't clear the control arm bushing and hang down too low. Also, the HUGE advantage of the stock headers is that BMW clearly designed them to be easily removed and replaced. Aftermarket headers usually require a painful amount of time with small turns on a wrench.