Thanks guys.
First drive impressions:
- The car runs silky smooth. Before it used to have a bit of a lope at idle, where the weaker cylinders really showed up. I had leakage through the valves before and of course this is going to be most noticeable when there's a lot of time for each compression stroke to leak out. Now it just idles like glass.
- Broken glass... The added valve clearances are noticeable. I didn't think they would be, due to the very slow open/close ramps. I will tighten them up after I retorque the heads, which I can do now that I've beaten up on it a little.
- At ~2300 the exhaust really begins to bark and resonate. It's sort of a high pitched rattle, rather ricey to my ears.
Beginning at about 4000 it loses the rattle and starts to sound more like a high performance 6 cylinder, and it sort of holds that to about 5500 or so, where it begins to tone down and sound a bit more strained inside the car. I don't know what it sounds like outside.
- The transmission that used to work very well with the stock B280F doesn't seem as well suited to this engine. It's fine, so long as I shift it manually, but if left in automatic it shifts by itself at about 4500 and doesn't let the engine breathe. Plus, I hate the sound of an obnoxious exhaust and an automatic...
- I was a bit underwhelmed with the power. Even though it runs much better and much stronger at the top end, well, I guess I had it built up in my head that I would change the spinning axis of the earth every time I stepped on the gas. I sure didn't MEAN to build up that expectation, which is completely unreasonable since AT BEST I was going to see 180 hp. I figure I'm probably pretty close to that, but it would really wake up with some B280E cams and an M46. Part of the underwhelming-ness probably came from the fact that I never really revved the old engine, because it didn't do any good. This one pulled strongly to 5500 and beyond on my first drives, but I didn't have much to compare it to.
- The engine ran quite lean on my first drive, around 13.7-13.2 to 1 at WOT, once it got off the oxygen sensor. Not horrible, but still probably giving up some power. Around town and on the highway it runs fine and stays on the oxygen sensor, so runs in the 14.5-15.0 to 1 range. Stomping on it at 100 kph drops it out of OD and into 3rd, where it pulls pretty well to 4500 and then back into OD at about 130. When it's in 3rd it is in the high 13:1 range, and then when it goes into OD it seems to mostly be back on the oxygen sensor. Good for economy, not great for power.
- Near the end of my run, after getting the tank to just over half on the gauge, I started to get some pretty good lean stumbles when I nailed the gas. Finding the pattern, it happened after a hard pull on the brakes and then getting back on the gas aggressively. It only happened once or twice, usually when I was pulling in 1st gear, and then it pulled as hard as normal from the next gear on.
Getting home, I pulled the in tank fuel pump and discovered that it was not working. It was giving me some troubles the last few times I drove it: when the weather was extremely hot, occasionally the car would die. It would crank, and once I pulled the return hose off the FPR and nothing came out, so it was fuel. I kind of thought the radio suppression relay was giving me grief, but that only triggers the injectors, not powers the fuel pump. Maybe the fuel pump relay was bad, and shutting off in the heat. I swapped them both last summer. I also had some issues similar to what I discovered at the end of my drive, where the car would stumble and stall sometimes on hard acceleration after braking, but I never had a wideband on it before now to see what was going on.
Anyway, after changing the pump I went for a quick drive and the AFRs were now in the low 13s to mid 12:1 range at WOT/redline, and it seemed to pull harder in the top end than before. It also failed to give me that stumble after hard braking, so I think the problem is fixed. Hopefully too, the fuel pump relay will stay cooler and will not fail me in hotter weather. I only did a short drive so I don't know if I nailed the problem or not, or if it has a bunch more power than before.
So am I happy? Of course not. I'd like to deal with the rice factor and I want more power, but I'll live with both for now. I think it now needs a manual transmission more than before, and that will work well with the locker, especially if I put a lighter flywheel in there. Next winter jobs... There are a couple other things to deal with after I get driving it, rattling door panels and getting the air/cruise functioning, but those are for later.
Next step, trunk and roof paint.
