So have you ever tried a 3" upper with the 2# lower? After I try it at 22#'s, I think I will settle back down to somehting a little tamer, as you have. With the gas available here it would probably be much smarter. What size belt would you think would fit the 3" upper and 2# lower combo?

Mark

 

Should be around 15/16psi maybe?

7.9 lower /2.5 upper =3.16:1x5500 motor rpm=17380 I get 22psi
7.9 lower /3.0 upper =2.63:1x5500 motor rpm=14480 Never tried
7.9 lower /3.5 upper =2.26:1x5500 motor rpm=12430 I get 10psi
8.9 lower /3.5 upper =2.54:1x5500 motor rpm=13986 I get 15psi
8.9 lower /3.0 upper =2.97:1x5500 motor rpm=16317 I get 18 psi
8.9 lower /2.5 upper =3.56:1x5500 motor rpm=19580 I get 26 psi

8.9 is my 6lb lower and the 7.9 is my 2lb lower. The numbers are wierd, but that is what my boost gauge shows. My boost gauge is analog so the #'s aren't 100% correct.

Here is the chip I'm using.(side two is the street side)