I'm replacing all the accessories and brackets on my 77 F100 with a 5.0 with brackets and accessories from a 90 F150 with a 5.0. The smog pump is not going on. I found belt routing and some information on Mustang sites, but I wanted to see what size belt you guys are running. I measured today and I just measured pretty much straight across from the A/C compressor pulley to the alternator pulley. I came up with right about 86 inches. On the Mustang sites it shows to use and 84.5" belt with the set up I'm running. Does that sound right or should I go with the 87.2" belt? What size belt are you guys with 5.0's with no smog pump running?

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Thanks,

 

belts are always kind of tricky depending on your setup... I can't speak to the 5.0L setup but what i always buy 3-4 different belt sizes and whichever fits the best with the tensioner I leave on there.... The rest go back to the parts store...

 

I did the smog delete on my '92. I wanna say it was around 88-89in and i had to remove the smog pulley. I may have the size wrong though.

 

here's what I would do...

Get a piece of string about 95-105 inchs long and run it around all the pully's and put a slip knot on it... use a breaker bar and socket to extend the belt tensioner 3/4's of the way open. Run the string tight with the belt tensioner 3/4 open/released (this might take 2 people). Then with the string tight at 3/4 of the way mark the spot on the string with a marker (so you don't lose the size if string slips). Open the tensioner all the way and take the string off to measure with a tape measure.

What you'll end up with is a belt size close to what you'll need and b/c you opened the tensioner 3/4's of the way there will be room for the belt to strech a little as it breaks in.

As I suggested eariler, you might want to grab the 3-4 closest sizes and put the one that best fits on and return the others.

 

Thanks guys, yea I'm gonna go ahead and buy the 84.5 and the 87.2 and I'll return the wrong one.

Thanks again,

 

Both of those were wrong and the 91" I got was wrong too! LOL I ended up having to go with an 89" belt.

 

not to say I told you so but that's why I was suggesting to measure it. Thanks for letting us know the results though!