|Originally posted by Raydar:|
When I had my Challenger, many of us (Challenger owners) participated in a "dyno day" at a shop near here.
The cars with the 18" (base R/T) wheels seemed to do incrementally better than the cars with 20" wheels.
Made more of a difference than we noticed between the cars with 3.73 and 3.94 rear axle ratios.
That's just it. Gears and tire diameters don't affect a dyno, but weight does.
I originally dyno'd my 3.4 at 187rwhp then I started moving to bigger wheels+tires for traction at the track and lost power. I'm pretty sure the weight difference was more than 10 lbs. I'm currently running 315/35-17x9.5's and dyno'd at about 164 rwhp. My original dyno was with 255/50-16x8's. Last year, I was running 275/40's on the 17's and dyno'd in the low 170's. My weight distribution also move outwards. It would be easier to spin the tires if the weight was centered towards the axis of spin. With the weight moving away from center, the load on the motor is increased.
[This message has been edited by lou_dias (edited 01-20-2016).]