What is the difference between the 77series(truck) and the 57 FIPK series? Is it just the metal pipe?

 

as far as i can see yes

 

Do you think it would add a difference in sound and performance

 

The 77 Series is a shiny metal tube. The FIPK is a plastic tube.

 

I heard that the FIPK was better. That the metal gets really hot. Just my .02 cents.

 

the only problem is that the metal gets hot from the engine and the air gets hot so the cold air factor is thrown out the window go with like a volant or banks

 

there are usually dyno charts flying around the web somewhere where you can compare your approx. increase. From what i've seen around and on my friends' trucks the plastic gives a couple extra horsies

 

I'm not sure about the 2001 model, but on my 2006, the FIPK was rated at about 15.6 horsepower and the 77 series was rated at about 10.7 horsepower. The 77 series metal looks nicer but the the plastic obviously performs better. I'm very happy with my FIPK anyways.

 

I put a k@n FIPK on my 1994 5.0 whith a throttle body spacer and there was a huge difference in the way my truck works.