Anyone realize how far off our tachometers are? According to my tachometer, my VTEC engages at 6000rpm on the dot. According to my dyno plot, it's engaging at 5700 on the dot. 300rpm may not seem like alot, but it is when it's critical to know actual engine speed for racing (drag etc...).

Anyone know why the tachs are "offset"? Do you think it's purposely done by Honda in order to keep the *actual* revs down on their motors?

In my Civics setup (LS/VTEC), at the track I had to shift at 9100 on the tach, which represented only 8400 true rpm... very strange...

 

I think the honda tachs rely on vacuum to determine rpm.
Thats why the higher the rpm, the less accurate they are.

 

I don't think that's possible... the car wouldn't know what gear it's in for a certain vaccuum etc... I'm pretty sure it's read off the distributor.

 

the actual rpm signal is accurate.

the reason its inaccurate on the tach is because its controlled by a coil.

 

My Tach reads 6150 when vtec hits.

Anyone know how to fix? Without a monster tach.

 

What rpm does your tach read when you reach redline/cutoff?

 

mine reads ~9100 or thereabouts at the rev limiter

 

~9100

 

mine reads ~8900 or thereabouts at the rev limiter

Will
-who had a peak hold reading of 8642 on the vafc this evening

 

Mine is at 8900k for the revlimiter and 6000k for vtec....

 

Around 9200 cut off.

 

good grief what kind of motor are you running? GE Turbine?

 

haha!

its NAWZZZZ y0

 

Mine seems to be accurate, for now anyway. VTEC and fuel cutoff seem to activating where they should. I wonder if over time the coil can deteriorate and start giving bad readings.

 

Mine's only off about 200rpm at fuel cut.

 

Same here, although I swear it used to be only 100 RPMs off... Is it possible that the tach reading becomes less accurate over time?

 

Maybe because your care revs faster since its rice oh i mean race spec?

 

LOL, could be...but the inaccuracy doesn't really bother me since I just use my bling-bling Autometer shift light.

 

Tizzite! Where do you mount it?

 

On the carbon-fiber quintuple pillar pod, duh!

 

On the dash...

 

My bad

 

Good place to mount if want hidden is in place of the Cruise control buton that you dont have in the R take it out a put the shift light in there nice and clean install

 

Except then it isn't in your line of sight when you are driving, so you might as well be looking down at the tach. Plus the light is blocked by the steering wheel...

 

not really dude. That thing is blinding.