XP Falcon inline six,worth rebuilding the original or swap to a Crossflow?
The original 170 cubic inch six in my XP is tired. It uses oil and the compression is down on two cylinders. I can either rebuild it to factory spec or swap in the later 200 or 250 Crossflow six which is more powerful and parts are everywhere. The car is a Deluxe in original condition otherwise. Does originality matter enough to justify rebuilding the original engine, or is the Crossflow swap so common that nobody cares?
For a Deluxe in original condition, I would strongly advocate rebuilding the original engine. A standard XP Deluxe with matching numbers is becoming genuinely rare and valuable. The Crossflow swap is common in modified cars but it changes the character and reduces the value of an original car. A full rebuild of the 170 six is about $2,500-3,000 with new rings, bearings, and a valve job. That investment preserves the car's integrity and you'll recoup it and more when you eventually sell.
Agree with GhiaGraham. Originality matters enormously on early Falcons now. The market has shifted toward valuing unmodified cars, especially the XK-XP series which are getting scarce. A matching-numbers XP Deluxe with the original engine is worth significantly more than one with a Crossflow swap. Keep the original engine and rebuild it properly.