Opel Kadett

vs

Opel Manta 400

Germany vs West Germany — 1975 vs 1981

Opel Kadett (1975)
Opel Manta 400 (1981)
Specifications
Kadett GT/E CoupeManta 400 Rally Homologation
Horsepower105 hp144 hp
Torque117 lb-ft155 lb-ft
Engine Size1,897 cc2,420 cc
0-60 mph10.0 sec8.5 sec
Top Speed115 mph129 mph
¼ Mile17.5 sec16.0 sec
Weight2,116 lbs2,337 lbs
Wheelbase2,518 mm2,518 mm
Length4,210 mm4,470 mm
Units Produced18,500245
Value (Excellent)$35,000$200,000
Collectibility6/108/10
Rarity7/109/10
The Verdict

The 1981 Opel Manta 400 Rally Homologation emerges ahead in most objective measures, offering more power, quicker acceleration, higher top speed. The 1975 Opel Kadett GT/E Coupe counters with lighter weight, better value, but the numbers favor its rival. Still, both are remarkable machines, and the final choice often comes down to which driving experience speaks to you.

Overview

The 1975 Opel Kadett GT/E Coupe and 1981 Opel Manta 400 Rally Homologation share a manufacturer in Opel, but that's where the similarities get interesting. These two models reveal the versatility and ambition of the Opel brand. The 1981 Opel Manta 400 Rally Homologation holds a clear advantage in raw power with 144 hp compared to 105 hp, a 39-horsepower difference that shapes the driving experience. Under the hood, the contrast is notable: the Opel Kadett uses a Inline-4 OHC displacing 1,897 cc, while the Opel Manta 400 relies on a Inline-4 DOHC 16V with 2,420 cc. In the sprint to 60 mph, the 1981 Opel Manta 400 Rally Homologation edges ahead at 8.5 seconds versus 10.0 seconds. The Opel Kadett carries a weight advantage, tipping the scales 221 lbs lighter. Rarity plays a significant role here — with only 245 units built, the 1981 Opel Manta 400 Rally Homologation is considerably scarcer than the Opel Kadett's 18,500 examples. On the collector market, the 1981 Opel Manta 400 Rally Homologation commands a significant premium over the 1975 Opel Kadett GT/E Coupe, reflecting differences in prestige and rarity. From a collectibility standpoint, the 1981 Opel Manta 400 Rally Homologation rates higher among enthusiasts and auction houses.