...blower belt restrict the amount of boost that you can achieve. I just installed a 2.70 upper with the Metco Idler kit. I have a 6# lower and was seeing right around 12-13 psi of boost. After the install of the 2.70, I'm seeing the same amount of boost. I put the belt that I used for the 6# lower back on. It was a tight fit, but it got back on. Do you think the reason I'm showing the same amount of boost is because there is too much tension on the belt? If so, what size belt do you recommend?

Thanks
Kurt

 

Its from changing the upper not doing crap to increase boost. Upper pullies are a waste of money. Get a bigger lower.

 

A tighter belt is a good thing.

 

Just FYI, if you went from a 6lb Lower and the stock upper (2.93) then the new combo 6lb lower and a SMALLER 2.70, the old belt would be looser.

Oh, I just sean you have idlers, well, let me check my graph and I'll get back to you...

p.s. A tighter belt is better.

 

YOu should see a 1.3lb increse in boost,

Blower RPMs at 5000 w/6lb and 2.93 = 15379
Blower RPMs at 5000 w/6lb and 2.70 = 16689

Blower RPMs at 6000 w/6lb and 2.93 = 18455
Blower RPMs at 6000 w/6lb and 2.70 = 20027

You sure you are not getting belt slip? Boost bypass not working properly? Guage calabrated properly? Good luck, hope this helps.

Lucas

 

I'll give it some time and then check for belt slip, but it doesn't seem to be a plausable answer because the belt, with the tensioner as loose as it can go, barely got over the idler. I have a boost by pass and I'll check the connections later. I have an Autometer boost guage, so I'm asuming that it is calibrated correctly. Thanks for the input though Half.

Kurt