There seems to be some confusion on whats the correct size blower belt for different lower pulley sizes...Does anyone have a reference handy? Thanks

 

Jeff I know I was told for a 4 lb lower and a Reichard 1-2 pound upper to buy a Gatorback ---675, and I believe for just a 4 lb lower a Gatorback ---680. I hope that helps a little. Todd

 

Belt Guide
Lightning: (stock upper)

REM 2lb pulley, use Gatroback 4080675
REM 4lb pulley, use Gatorback 4080680
REM 6lb pulley, use Gatorback 4080685
REM 8lb pulley, use Gatorback 4080690
All applications are measured with OE Lightning Upper

 

Just to make sure I understand the length correctly 4080690 is a 69" belt and 4080685 is a 68.5" belt right? There is a vendor here telling me different....

 

Below is some pulley and belt info I gleened off the boards over the last few months:

Lower Pulley measurement:
Stock = 7.5"
2lb = 8.0"
4lb = 8.5"
6lb = 9.0"
8lb = 9.5" I think ...?

Goodyear Gatorback 4080660 SC Belt
1999-current Ford Lightning & 2003-current Harley-Davidson F-150
*** to be used with 2 lb. Upper & Stock Lower SC Pulleys ***

Goodyear Gatorback 4080670 SC Belt
1999-current Ford Lightning & 2003-current Harley-Davidson F-150
*** to be used with 2 lb. Upper & 3 lb. Lower SC Pulleys ***

Goodyear Gatorback 4080675 SC Belt
1999-current Ford Lightning & 2003-current Harley-Davidson F-150
*** to be used with 2 lb. Upper & 4lb. Lower SC Pulleys ***

Goodyear Gatorback 4080680 SC Belt
1999-current Ford Lightning & 2003-current Harley-Davidson F-150
*** to be used with 2 lb. Upper & 6 lb. Lower SC Pulleys ***

Here's the GatorBack part number for the -accessory belt- on an L: # 4080990

NOTE:
You L owners, anywhere it says 2# upper this is stock upper..

 

Someone should have a spreadsheet on all the applications people are running and the correct beltsizes...I am running a 8# lower and a 2.70 upper with a Metco 100mm idler and I use a GB 4080680.....

 

I have a 4lb lower and sotck upper with a 68" Napa belt.