B- Mods are everywhere nowadays, and becoming one of the fastest-growing classes in the country and this is why we need to cover the shock and spring setup for them. With many options available in chassis, some of them are changing the way need to look at what is to be done. Chassis are becoming lighter and more flexible which is allow the car to make up for some of the setup. This is okay but comes at a price when it comes to traction.
We are going to cover these subjects in this video on setting up a B-Mod and we will leave the facts here.
· Ride Height:
· Spring Location:
· Spring Rates:
· Wheel Loads:
· RR Wheel load procedure:
· Shock Valving:
· Loading the rear Springs:
· Scale Numbers:
Ride height:
· RF 7.50
· LF 7.625,
· RR set per chassis, understand pivot point location.
· What is the pivot point,
Spring Location:
· LR spring in front on slider USRA
· LR spring on top IMCA
· RR spring on top
· RR spring in front
Spring Rates:
· RF 500-550
· LF 550-600
· RR 225 x 13 on slider
· RR 250x11 spring on top USRA
· RR 225x13 spring on top IMCA
· LR 175 x 13 slider in front
· LR 175 x 13 slider in front (cage preloaded)
Wheel Loads:
· RF (ride height) 600
· LF (ride height) 750
· RR: 375-400 at ride height
· LR if running a 125 x16 only (185-225 extended load)
RR wheel load measuring procedure:
· At ride height
· 13 minus 11.375 = 1.625
· 1.625 x rate = load
Shock Valving:
· RFGF-300/130@100PSI (SRT BV options)
· RFAD1-300 (adjustable USRA legal)
· LF1-75/160@100 PSI (SRT option)
· RR1-40/110@100psi (SRT, BV option) add rebound in slick
· LR1-75-550 SRT @300psi
Preloading the rear shocks:
· RR load
· LR load (125x16 extended @ 185-225) USRA (Not for IMCA)
· LR 175-250 run on a bite number.
Scale Numbers:
· RF: 500
· LF: 575
· RR: 660
· LR: 725
· Total: 2460
· Left Side % 53.5-54.5
· Rear % 54-56
· Cross % 49-51
· Bite: 40-100 lbs. (the more bite the tighter the car)