There are a ton of threads on this topic. I've searched for and read all that I can find. I know how to do this, but I'm confused on belt length. I've found a diagram with the belt routing and length but its for a 95 f150 5.0. I have a 90 f150 5.0, would the belt length be the same? Both of which have AC

 

Gotta make sure the brackets and pulley sizes are the same 90 to 95 for that measurement to work. As I recall, that smog pump was originally added to keep the engine from backfiring on deceleration

 

Well I did a little research and the factory belt length for my truck is 91.750 inches and the factory belt length for a 95 f150 is 99.375 inches. So I found another belt routing and length but it was for a mustang 5.0. I checked and a factory '90 mustang 5.0 belt is 91.125. So with the lengths that close I assume the length and routing for the mustang would work in my f150.

 

For my 92 5.0 it's Dayco 5060895 (89.5")

 

No, the smog pump causes backfiring on deceleration if it doesn't divert the air properly.

 

Well guys I took the pulley of and ran the new belt. The 84.5 was too short so I got a masterpro K060878 that was 88 3/8" long. Fit good

 

My truck used to backfire on deceleration

 

Here's an update I removed the smog pump and all related hoses and plugged the heads. A little more room under the hood now. The truck runs better now and I noticed the idle got smoother. Looks much easier to change spark plugs