My 521 dyno data

[John Owen]

Hi Frank -
The usual hp and torque loss range for the drivetrain is 15-20%, with automatics losing more than manual. Assuming a 17% loss for my setup, 503 rear wheel is about 605HP at the flywheel, and about what the motor should produce. I have 55# injectors, but failed to note the duty cycle - sounds like I need to take a road trip with the computer hooked up, just hard to drive and play with the computer. I think my loss with a Torker II would be in the 100HP range because I kept the solid roller cam which is at the upper range for street use and needs good higher RPM flow to make power.
As to traction, I use BFG TA/KD 275 17 on the rear and they behave very well on dry pavement. In 1st or 2nd the tires can be broken loose at most any speed without using the clutch, but the tires never just go up in smoke- back off a little and they regain grip quickly. In 3rd they begin to slip a little at the high end of the power band but still accelerate strongly. No problems in 4th or 5th. Wet roads are a challenge.