The Librands manifold and exhaust definitely improves performance significantly as many have said, however I have found an intolerable drone from about 1900- 3000 rpm, which unfortunately on the roads around here is a lot of the rev range when touring.... And sometimes no amount of gear changing can seem to shift it... Hence decided to keep manifold and cat and swap the system back. I read someone on TM has done similar and found no noticeable difference in power.. Henc going to try this.
Hi Steve & welcome. Lovely car (and tractor).
Notwithstanding that my experience relates to a 1.6 Sigma rather than your 1.8 Zetec, I would be wary of putting a more restrictive cat-back system behind the freer-flowing manifold and cat.
This was my initial route and made the car sound shrill and strangled - a very unpleasant note. Bizarrely, a side-exit exhaust gave the best combination: whilst the exit is closer to your ears (or your passenger in your case!) the droning resonance from the back-box is lost, the exhaust note is nicer because there is less restriction, and even though the volume is higher at higher revs this tends to get 'left-behind' as you are travelling more quickly.
(Caveat: this is all roof-down. Never use the roof so I don't know if this would change how much sound stays in the cockpit at speed).
