You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!
Possibly; if you get a new, higher-flowing exhaust, your backpressure is lowered. Backpressure helps your truck make low-end torque, but it also means that your engine has to work harder to expel the exhaust gases. So, putting flowmasters on might fractionally help your gas mileage, but not by much. A whole new exhaust system would further lower your backpressure and might also fractionally improve fuel efficency, but again, it will not be much.
the flowmaster should help over stock, but it won't be a dramatic gain, besides, there's always that testosterone factor, you hear the nice tone, and you tend to try to keep hearing it... but free flowing exhaust has been well proven to improve efficiency. That is what is behind the talk of 10-20% gain in power and economy by adding headers...
__________________
the workhorse:86 F250 4x4 6.9 Diesel 4-spd, 4.10 axles
the other workhorse 92 F350 2wd crew cab,3.55 rear axle, 92 6bt Cummins, NV4500
the project: 78 F150 4x4 shortbed 351 auto Iowa Chapter leader, ASE certified parts specialist
Come on down and join us in the Iowa chapter, or your own local chapter!! Thanks, Roger
fellro is correct, technically the flowmaster should help gas mileage but usually you tend to rev the engine and use excessive throttle and mileage drops. At least for a week or two until you adjust to the new sound
The backpressure=low-end-torque theory is crap. You want NO backpressure. I have a flowmaster, but didnt notice that much of a gain. I get 12-13MPG no matter how I drive (80mph HWY or 40MPH in-town).
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.
