Yeah, Duke, I agree on the cam specs on the 103; definitely a high RPM spec with pretty tight LSA. Mine pulls about 16 vacuum, which at first made me look for vacuum problems, but turns out that's pretty normal.

Biggest issue I've had with idle over the last 25 years and 250k miles was by far motor mounts. Brand new off-brand mounts will rock and vibrate like crazy, making you think the motor is missing badly. I tried 4 different brands, they all shook the engine from the get-go and collapsed in a few thousand mile or less. Finally spent $150 on OE and problem solved.

Second is cheap injectors. I've bought about 3 sets in the last 25 years, and gotten some obviously pretty poor flow matches. Last set I got is pretty good, and she idles very smooth and gets better mileage. Don't know if OE, at 5 times the price, would guarantee good flow match; best bet might be to buy cheapies and get them tested.

DG