Helping a friend rebuild a 1977 mc5 250 He has two exhaust pipes,one original 1977 mc5 exhaust and one off a 1978 mc5 250 both great shape. Has anybody done any testing which puts out better over all horsepower. Any help would be great thx again.
The 78 puts more torque at the low end. Will require different exhaust , use a 78 angled manifold.
Yea 78 WAY better!