This past Saturday as I was about to take my 1990 Spider Quadrifoglio out for a ride, I experienced the car not wanting to go beyond 2500-3000 RPM. It starts fine, idles fine, sounds fine however during revving and driving it just does not want to go further than those RPMs. Any ideas what it could be? These last couple days of thinking and poking around got me wondering is it a fuel delivery problem? Timing? Exhaust issue? Has anyone else experienced this? Thanks for any feedback!