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I am looking at ordering a blueprint 383 with aluminum head, roller cam etc. for my 55 4DR marrying it to a TH350 with a stock rear. Running out of cash :) Considered the GM ZZ4 but worried about lack of HP / TQ. Now for my ridiculous question: what kind of mpg should I expect? I am serious. Thanks.
 

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I am looking at ordering a blueprint 383 with aluminum head, roller cam etc. for my 55 4DR marrying it to a TH350 with a stock rear. Running out of cash :) Considered the GM ZZ4 but worried about lack of HP / TQ. Now for my ridiculous question: what kind of mpg should I expect? I am serious. Thanks.
It depends on a few factors. First, the TH350 is not an overdrive, so you need to consider what rear gear you will be using. I imagine something below a 3.42:1 rear gear. Second, what size carb you will run will be a factor. A 383 will probably run best with a 670 or 770 carb, but as I have a ZZ4 with aluminum heads and roller cam going in to my '55 4-door, you need more low end torque to get the car rolling, and I have a Carter 625 that should work very well. In all honesty, if you are concerned about fuel mileage, then frankly I'd go with one of the crate ZZ4 engines with the accessories. I know money is tight but when you add all the items onto the 383 that you need to get it running right, I think the Fast Burn 385 might be a good option.
 

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HP

Just remember High horsepower and good fuel milage are on opposite ends of the spectrum (especially when using a carb) . Every horse needs the same amount of fuel to keep it alive. if your looking for fuel milage, look for as lower horse fuel imjected late model engine with computer and overdrive tranny. Later change the rear gear for something better,
 
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