My timing chain at 2mm valve opening with 17.5 to 18 degrees ATDC of stretch (13.5 is normal) had these operating characteristics:

started easily
ran smoothly
loss of power up hills
slower than normal acceleration
on a flat road would cruise at 70mph, but slowed down up almost any hill
excessive black smoke out of exhaust on start-up and warm-up
excessive black smoke when the accelerator was opened to full open position or close to
fuel efficiency dropped

Hope this helps!
Tom

__________________
America: Land of the Free!

1977 300D: 300,000+ miles

American Honda: Factory Trained Technician & Honor Grad.
Formerly:
Shop Foreman;
Technical Advisor to Am. Honda;
Supervisor of Maintenance largest tree care co. in US for offices in Tex.