New Serpintine belt, less boost??

[Riceater52910]

So heres the problem, popped the hood on the Cobra one night and noticed the belt was coming apart. So i replaced it with the exact same brand, the Gatorback 75" Belt. My car has a 2.76 upper with the BF 4 piece idler set. I immediately noticed a loss in power. Now heres the thing, my car normally runs about 14psi on the gauge. With the new belt i get about 11 to 12psi. So i returned the belt and went with a Gates V series 74.5" belt, same problem despite being twice the cost. Everyone keeps telling me belt slip which makes obvious sense but why would the old worn out belt grip better than a brand new one??

 

[BBCOBRA]

It sounds like something else is going on. Check you connections at the air intake, MAF, IAT sensor.

 

[68_GT]

Everyone keeps telling me belt slip which makes obvious sense but why would the old worn out belt grip better than a brand new one??

can't be....as stated above there has to be something else going on. I wonder what else can cause a loss in boost ???? Was the car otherwise running fine with the shredded belt on ? did you put the old worn out belt back on to see if your lost boost came back ? Now I wonder why your belt shredded. Has your blower been worked on ?

 

[Riceater52910]

Ya it ran fine with the old belt, still hit 14psi like it should. Ive noticed since i changed it theres a new noise emitting from the engine bay. Its a whistling sound, possibly a vacuum leak but i cant find anything visible. I think ill try putting the old belt back on and see if that fixes it. Hopefully it doesnt because it just has to be something else. The blower has a stage 3 port that was done a couple years ago. I wonder if the problem could be the blower itself, possibly causing belts to come apart? The new one still looks fine after a few days though.

 

[68_GT]

whisteling noise, shredding belt, loss of boost ???

could it be a bad idler ? wondering if a failing / dragging idler could be causing your belt to turn slower ? Your belt shouldn't be shredding and a failing idler can squeal.

just a random thought. damage the tensioner swapping the belt ?

 

[speeddemon2000]

I tried the gatorback belts and noticed less boost vs the gates belts. I stuck with the gates belts and never looked back. "68 GT" is right about the a bad idler. Check your bearings. I usually replace the bearings in my idlers once a year. Billet flow sells replacement bearings.

 

[Furinox]

the gatorback belts are horrible. Those stupid cross grooves in the belt just make for less surface area for the belt to grab onto the pulley.

 

[03cobra#694]

I`m really liking the damaged tensioner thing that 68 GT posted.

 

[Riceater52910]

How can i check too see if the tensioner is bad? Its definately tight with the 74.5" Gates belt on. I pulled my idlers the other day, the snub idler was pretty bad. Made a grinding sound when i spun it. Where can i find Billetflow replacement bearings? I have the 4 piece set.

 

[BBCOBRA]

just go to any auto parts store. the skf bearing part number is 6203-2rsj. They are about 9 to 10.00 each.

 

[postalbunny]

I had a gates on that started to squeal on startup... after warm it went away. Put a gatorback on and it stopped instantly. Now to see if it starts up again in a few months.

 

[mooch91]

Riceeater...
Any updates on if/how your problem was solved?