Im planning on doing some road course driving this summer so I went out and got a small aftermarket tach so I dont have to constantly look down. Can I just splice into the back of the guages since there in a tach alreaddy on it? And if so what colors are what?

 

you won't get an accurate reading doing that....the stock tach is about 100-150 rpm off at idle and up to 500rpm off on the high end (5k-6.5k)....best bet is to just install the aftermarket according to manufactures instructions you will get the most accurate reading possible....

 

Ok thats kinda what i figured... thankx

 

Are you sure bout that man cause when I was hooked up to the scanner it said 750 and so did my tach, then when we went on a road test I hit 6k on the tach and the scanner said 6080...

 

Yes he is right about 1 of 2 things
I have a 2" tach in my SS/SC Pillar and it reads exactly 100 rpm off but it's definetely not off in the high end 5-6k rpms. I don't know maybe that's only if you splice into you stock tach wires.
I'm running the MSD Tach Driver that gets a signal right from the ICM and creates a tach signal that you can use with any aftermarket Tachometer

 

my car's tach says it idles around 825-850 but when i had the inspection done it was idling at 773....and i know that the engine redline on the 07 is around 6200 but my tach will show that i can hit 7k....and it's notoriously know that stock tachs are always inaccurate that's why many people that actually race for a living always have an aftermarket tach installed for the most accurate reading....

i noticed the other day the car felt like it was "camming" basically idle low then idle a little higher (you can tell because the car makes a different sound and it vibrates a bit more) and the tach didn't move at all...but the vacuum gauge was jumping to the synch of the vibration....

if i think about it later i will take a video of it...

 

You live close enough, if you go to the meet just show me there... that is crazy bro my tach is really sensitive, it seems to even move when I fart.

 

So would all of you say that its best just to home run the wires rather then splicing?

 

you can actually get the proper signal off the ICM without a tach adapter

just set the cylinder output to 2 and you get the proper reading...just FYI for anyone wondering

 

Yes that's true only most aftermarket Tach's only go to 4-6-8 Cyl. and you won't see many that have the 2 Cyl. option
The Steward Warner Digital Tach was all I could really find that had 1 to 12 Cyl. option

 

hmm, my Zex window switch and Raptor shift light both have a 2 cyl mode so no probs for me

 

first off why do you need a tac in an automatic?

 

Very good question. He might just be curious.

 

its not like he has to worry about shifting