hey folks.. i just had a question..

In my previous 92 cx hatch i had 15' in wheels and my b16 vtec would kick in at 5700 rpm according to the tach.. but now in my new found 92 vx it seems as if vtec is engaging at about 6k rpms.. but I have 13' in wheels instead.. From what I remember.. its like bigger wheels/tires = more mileage etc and will also affect what the tach reads.. so would the tach just be off because of wheel/tire size or is something wrong?

 

It's just the your tach being off (generally while measuring the optical rpm of a motor on our dyno we see about a 300-500rpm difference over the cluster up top). Tire size has nothing to do with rpm or what your speedometer is reading. It does however deal with your actual ground speed of your vehicle and how fast you are <U>actually</U> moving when VTEC crosses over. So say you're getting shot by a cops radar or lidar gun right when your VTEC engages, you will be shown moving slower at that point in time with the 13 inch wheels/tires (if your overall diameter is smaller) than on the 15 inch wheels. Hope this helps