the car should perform like this.
at a light/stop, floored it should pull weakly, then as the RPM's climb toward 2000RPM, it'll pull much harder to the point where cornering is difficult. on a straight pull, the car will hit the 2K mark about 12mph. it should pull to 4Kish when floored, and jump into 2nd gear at about 20mhp, then pull solid to 4K again at around 45mph, then shift into 3rd where it will pull until you get startled with the speed, or 75mph whichever comes first. if you carry on, 4th will engage there, and the acceleration will gradually continue until you lift your foot off the pedal. I think the car tops out around 108mph, but it'll be a LOOONG time before you get that fast.
if this does not sound like your car's performance, let us know.
I'd really like to see a pic of the motor. your comment about the broken tube, makes me think you have an amalgamation of N/A and Turbo parts in your car...