I have 2 Boxtype, one a stock 1400sl and a 1600sl with saturn engine and webber carb. I dont think the 1400sl is slower than a kia pride, i can reach 140kph on its 4 speed transmission. Something might be wrong with your engine.

I can't say that my 97 civic lxi is faster that the 1600sl, but the boxtype has a lot more torque that my honda. Although both cars can reach 170 in a nearly the same amount of time.