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Join Date: Jan 2009
Location: Northern Hemisphere
I would start with a good tune up, check your fuel and air filter, distributor, wires, etc. Once you know that this is good, I would see how can you increase the HP. Do you have headers?
I have a 1970 wagon with SBC 350 and like Big Dave said, the car weights two tons so it is not a speed demon. Bob is also right, check your rear gear ratio. Mine is setup with 2.59:1 (if I remember correctly) so while the highway speeds are good, it takes a while for the car to keep rolling.