In that car-you said no shock towers????????? with that size engine, and that stroke, the tuning of the primary tubes won't be as important as just getting the exhaust out of the cylinder/head and away from the motor--------your first bend or two will be criticle as well as how you merge the tubes to the collector-probably more than the primary tube lengths-having said that---I usually look at seeing if I can alternate tube lengths according to firing order to end up with two combos of primaries about 3 or 4 inches different simply so as not to tune in the engine at a particular rpm but broaden out the tune rpm?????????????? If you look at some of my old records--it musta worked!!!!!!!!!!