Long Tube Headers and Gas Mileage MPG
#1
On The Tree
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My car is in my sig. On a stock car will long tube headers w/high flow cats & w/dyno tune improve my gas mileage MPG?
#2
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I can't be 100% sure about the mpg increase. Logic does tell you that if you increase the amount of exhaust being removed from the system that increases the efficiency which then will increase your mpg. However longtubes effect each car differently some run rich,lean,or just fine. It just depends on what the tuner has to do with your tune.
#9
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I would probably go with the 1 7/8, but the 1 3/4's would work absolutely fine for your application. It's just that it seems with the 1 7/8's you have more room to grow if you plan on modding the car heavier in the future.
#10
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I doubt you will see an improvement. More likely the headers will make
your O2 sensors sleepy and cause overfueling by mistrimming, and even
when working they will be slow and swing wide.
Theoretical efficiency is all well and good, but there's plenty of reality
going on and not all of it's helpful.
your O2 sensors sleepy and cause overfueling by mistrimming, and even
when working they will be slow and swing wide.
Theoretical efficiency is all well and good, but there's plenty of reality
going on and not all of it's helpful.