This is an easy bolt on part on my 94 Ford 351w but it makes no difference in mpg, torque, etc. Heard they don't do anything at all so I went with this cheap one instead of the more expensive. I mean if I'm going to throw money away it may as well be a small amount
Recently put this part on my 88’ F-150 was apprehensive about it. But I am actually very pleased, my truck idles much smoother and I can tell a difference in my low end torque and power.