H22A vs B18C mpg in 5th gen civic hatchback?


New Member
I am planning to swap my 5th gen civic with either a H22A or B18C because they have an alright amount of power and dont get terrible mileage in the vehicles they come in. I was interested in what mileage you guys are getting with your swaps, I assumed the H22a would get worse MPG because its heavier and makes more power but in the forums Ive been seeing most people say about 23-27 for the most part, some saying as low as 18 and as high as 31. For the B18C to my surprise most people were saying 17-25. So I wanted to ask you guys here who have done either swap and figured out the MPG. mileage is my main concern because this is my daily and I drive about 200-300 miles a week and gas prices here in California are ridicules. So if you guys have any information on what mileage you get and would mind letting me know how hard you usually push your car that'd be awesome, thank you=)


Mr. Search
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5+ Year Member
10+ Year Member
Based on what I have read from others over the years, don't let this be your deciding factor, you won't see much of a difference in fuel economy, not enough to sway one way or the other.
They're Honda engines, they were built for performance and fuel economy.
Also, you'll have to factor in the health of the engine you're putting in, how well is it running with how many miles on it, what has been done, what does it need?