I know from my HPTuners that the 1-2 and 2-3 shifts are set for 6000, but 5600 in hot conditions. Today was definitley not hot, but the tach only reads about 5700 on a 1-2 full throttle shift and maybe a little higher on 2-3. Does anyone know if the tach is actually lagging, especially considering the blistering nose bleed inducing accelleration (well maybe not so much) in the lower gears?

Thanks

Have you looked at your Hp scanner Gauges . My tach on the dash lags the scanner

The tach in the car is slow as all get out. It is every bit of 250 or more rpm behind the actual tach signal the ecm is seeing when going wot.

The tach in the car is slow as all get out. It is every bit of 250 or more rpm behind the actual tach signal the ecm is seeing when going wot.

How hard would it be to fix this issue?

No way to fix it, lag is more than likely due to the tach signal going to the ecm then over to the bcm and then over to the cluster.

That is the reason hp tuners reads it correctly as it reads the signal from the ecm.

I doubt there would be a feasible fix for this.

The tach in the car is slow as all get out. It is every bit of 250 or more rpm behind the actual tach signal the ecm is seeing when going wot.

:iagree: Figured it out the first time I hit the rev limiter in second gear when the tach had barely crossed 6k. Now I just shift at what looks like 6K in both first and second.

Yup its slow :( My GXP in first gear is into the limiter at 6800 RPM when its showing just over 6000 on the tach:\ I've got one of my Aeroforce gauges setup as a shift light currently ;)