Hello,

I just recently bought my 2004 F-250. It came with straight pipes on it and I'm not a fan of them. Can you please tell me what I need too do to increase power. I feel like the straight pipes are reducing the back pressure. The take off with my truck is very slow. It takes a while to get rolling but afterwards its fine. I have always used flowmasters on my previous Mustangs. Thanks for the help.

 

The requirement of backpressure to make HP is a fable.
There's something else wrong if the truck is not making the power that it should. You don't mention what engine / transmission combination you have so it's a guessing game - but - it may be possible that o2 sensors may not be getting a good reading and that is messing up your air/fuel ratio..
Does the truck have any codes stored?

 

Sorry for the lack of information. I have a 2004 F250 crew cab with the 5.4 Gas engine and a 4" lift on it. The tires are 35/12.5r16. No codes no engine light. Seems to be running smooth just lacks power on take offs. It idles good doesn't seem to be miss firing. I have a K&N air filter and im going to be changing out the fuel filter and plugs this week. Not sure if it has been changed by previous owner recently so ill start by doing the regular maintenance.

 

I would recommend cleaning your MAF sensor with the appropriate cleaner. K&N type filters are known to allow the oil from the filter to get onto the MAF sensor and cause issues. It would be cheap insurance and good preventative maintenance.

Also, if you suspect something is not correct, you can get codes scanned and chase down issues from there.

 

I will add that to my list MAF cleaning. Thanks for the tip. An easy cleaning can make a big difference in performance.

 

That's a help having that info....

I think the tall tires will be hurting your bottom end performance most of all unless you have considerably steeper gears than the 3.50 gears that many trucks come with stock..
Getting things in good tune will be a good start.
For the sake of your own ears and those of your neighbors, please consider putting some mufflers on the truck to cut down the racket.

 

Take a good look at your gear ratio. The taller tires are your main problem.


Plug in your gear ratio and tire size here and see what you need to do to get back stock.


Tire Size Calculator

 

Thanks BIG Foot for the info. Cut racket down ha I might just have to keep it if I know its pissing the neighbors off. So will the straight pipes hurt the performance besides the bigger tires ? I forgot to mention that the straight pipes go from two to one back to a two for dual exhaust. Should I run a bigger diameter single pipe with a muffler ? Thanks

 

Question for MSGTORG, I went to the website and plugged in my tire size but didn't see anything about the gear ratio. How do I get the ratio ?

 

sorry msgtorg I figured it all out. I def. believe that gear ratio is killing me. Where would you recommend me looking at buying new gears ? Thanks for all the help