is it possible for tachometers to be in acurate? at idle it seems to read correct but driving down the street i watched it as the trans shifted. the tone of the engine only sounded about 3000 RPMish but my tach was reading about 4000+ rpm. i am running a pro billet msd distributor, msd 6AL and blaster 2 coil. this is my first car with a high stall torque converter, its a 3800. i floored it and simulated a pass and i saw the tach go to 7000 rpm and didn't bounce my 6800 limiter chip. could i not be used to the stall speed of the converter and thats what seems odd or could my tach be off by that much? any ideas?

Running a MSD 6AL, you may need a tach filter from MSD. MSD instructions suggest?

whan i installed the ignition system i dont remember seeing anything about a tach filter. i've had the system on the car for over a year now and it seemed acurate for a while then all of the sudden it seemed off.