tx_zstang

Adjusting that idler wont help. You still need a better tensioner.
Have someone rev your motor while you watch the tensioner and belt...and image how much more extreme it'd be at WOT and higher rpms!

The local friend tried running his partially (1-rib-gone) belt, reversed so the side that was shredding (engine-side) was reversed, putting the good/clean side of the belt on the side that was shredding; and driving the car very easy for a few days, taking easy shifts, etc. The intent of this experiment was to see of there was any alignment issues, which if there was, it should have wore/shredded the same engine-side rib, even when driving easy. After driving around like that, taking it easy, there was NO visible sign of wear, shredding, or deterioration. He's buying a tensioner to replace the stock one, and we'll see how that helps.

(you need a 1/2" drive wratchet or breaker-bar for the stock 4.6L Mustang tensioner.)

2007CalSpec

I have a UPR billet tensioner. No thrown belts yet. I also carry a spare belt and breaker bar in the trunk.

SamsBlueGT

Thanks for clarifying, I was worrying I was leading the OP wrong there...

danzcool

Oh, that would be me. I think the first response said 3/8" or 1/2" depending on year, I was planning on verifying before throwing a wrench in the trunk.

Oh, and earlier when I said alignment looks good, I was just being California laid back in my speech pattern, so, what that translates to is that the mechanic checked the pulley alignment and found it to be spot on.

Anyway, hopefully the car will be back on the road tomorrow. Ordering direct from Whipple has had some challenges, I called and then faxed an order on Monday, apparently it got lost, so I had to do the same on Tuesday, called immediately after faxing and had the nice woman who answered the phone walk it into the guy who handles orders and asked her to verify with him that everything was fine. Called the next day to check to see if it shipped and found out it had not but they claimed it would ship... asked for a tracking number, but it had none then, asked to be notified of the tracking number. Still nothing, may have to call again if I don't hear or see anything in the morning.

Diabolical!

Whipple makes great products, but their distributers are much more customer friendly when it comes to ordering. Just look at Whipple's website and see if you can figure out how to get your hands on some of that awesome apparel.

Simon1

To keep a belt on your twin screw:

Alignement ( it has to be MEASURED-eye balling doesn't work.)
Properly sized (smallest possible with most belt wrap)
Don't hit the rev limiter
Don't powershift (or be ready)
Good tensioner

The end

danzcool

I nearly lost it when I went to pick up my car. (again, had it towed to a ford dealer to take advantage of ford roadside assistance towing, one hour labor at the dealer sounded better than the towing charge from the middle of nowhere). Somewhere along the way, the service advisor ended up with someone else's number, so I wasn't being updated. I called earlier today and he assured me it would be done by the end of the day, when I got there around 5, the mechanic was saying the belt I ordered from Whipple was too short, I knew it wasn't, so I go back with the service advisor to look at it and mention that the routing is correct and that the belt wil fit, he just needs to loosen the adjustable idler, route the belt, remove tension, move the adjustable pulley as far down as possible, torque down and then release the tensioner. It's a 5 minute issue. It ain't rocket science. I was ready to tell them to push it out onto the street and I would come back with tools the next day to git'r done. The service advisor understood what I was saying, shoo'd me into the waiting room so he could talk to the mechanic. It was ready 10 minutes later. But wow, I guess I've been lucky with my regular dealer and their competence level.

All right, aftermarket tensioners, what's good and what's a waste?
I saw a couple of endorsements in this thread for the thump racing one, and a few who didn't specify which aftermarket tensioner they were using. Any opinions on steeda or upr? Any others?

Simon1

I can only speak for the Steeda piece. Bascially, they weld a 3/8" inch peice of billet alluminum to the outside of the arm to make the arm less flexible. The spring feels the same, but it could be different. It also has a really nice polished billit pulley on it hat can be used for atleast the 8 rib set up, maybe even 10 rib.

forensicsteve

Not sure what would have prevented this

turbo .... they rarely have belt issues

07VistaChicago

Due to this thread I picked up a thump tensioner with 76mm and a 90mm billit idler and a 100mm billit idler for $150. Is this all I need?