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jzrvinit's avatar
jzrvinit
Explorer
Oct 13, 2014

F53 (2004) Test, Interesting.

Wanted to share...

I have been reading on the ford truck forums how restrictive the exhaust system is on the F53 V10 chassis so I decided to do an experiment. I added the programming from 5 star last year.

I replaced the y pipe and removed the muffler. Then drove 800 miles in 2 days. The cat remained in place.

Normally my RV will get 5.5 to 6.0 mpg consistently.

Interesting? This trip the RV got 8.0mpg to as much as 10mpg average when on level ground. Power increase was (by the feel of my backside) significant. She was pulling hills at 60mph on 81 surprisingly well.

So now I assumed there was a blockage at the muffler. Nope all was good. Only issue, wow was it loud up hill, need to get a low restriction muffler on it next.

Normal low speed driving, not bad, even livable, sounds like a hotrod. At an idle, amazingly quiet... Not on a hill however..

Any recommendations on a muffler?
Class A

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  • Daveinet's avatar
    Daveinet
    Explorer
    Oct 13, 2014
    Yes, Magnaflow. straight through perforated pipe is going to be the most like any open pipe as you can get. There are all kinds of tricks manufacturers have tried to pull, with some working to various degrees, but nothing will compare to a straight through muffler. I tried a coupe of different Flowmasters, which had measured performance loss - the 70 series killed my fuel mileage and were still noisy. Lost 10% on my zero to sixty times. My experiments were with no other changes other than mufflers. (although I did some tuning attempts to try to "fix" the Flowmasters based on their ignorant customer assistance recommendations)

    BTW:The older V10 is well known to have breathing issues. One indicator is if you look on the Banks website, you can see their test results, which are substantial for the older V10. In contrast, the newer V10 does not gain much.

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