Aftermarket tachometer

[wesinls]

Hello All,

I'm hoping some of you experts can give me some advice...I have a hayabusa motor in a car and have a autometer tach hooked up to it. I sent the tach off to autometer to get calibrated for 1/2 pulse (there recommendation), now my motor idles at 2500 and gets to 10 grand at about 3/4 throttle. The tach is hooked up directley to the tach signal wire coming from the ECU. Autometer told me to try and hook the tach to one of the negative wires coming from the coil packs. I tried that, and nothing. So my questions are:

Is 1/2 pulse right?

Can you even hook a tach up to the negative wire on the coil?

Did they just calibrate it wrong?

Sorry for the long post, and thanks in advance for any info!!!

Wyatt

 

[wesinls]

Hello All,

 I'm hoping some of you experts can give me some advice...I have a hayabusa motor in a car and have a autometer tach hooked up to it.  I sent the tach off to autometer to get calibrated for 1/2 pulse (there recommendation), now my motor idles at 2500 and gets to 10 grand at about 3/4 throttle.  The tach is hooked up directley to the tach signal wire coming from the ECU.  Autometer told me to try and hook the tach to one of the negative wires coming from the coil packs. I tried that, and nothing. So my questions are:

Is 1/2 pulse right?

Can you even hook a tach up to the negative wire on the coil?

Did they just calibrate it wrong?

Sorry for the long post, and thanks in advance for any info!!!

Wyatt

Pic of car motor is in, if anyone was interested...

 

[RyClef331]

BUMMMP! Anyone know the answer to this man's question! I've got a busa rail too and the same problem

 

[danemsteve]

hi, does anyone have an answer to this problem?? as i'm in the same boat! or should that be car or bike!

 

[danemsteve]

this is my car!

 

[BusaWhipped]

Can't help you with the tach circuit. But if you want to try pulling signal from a coil, tap into the White/Blue Trace wire coming from the ECU. That controls Coil #1.

 

[twotonevert]

Wish I knew, cool cars guys.

 

[danemsteve]

thanks for the quick reply busawhipped. Ive tried No.1 coil but it makes it worse! i used to run a highly moded GSXR1100wp and have changed to busa power! 1350cc (ross racing pistons) bilt cam lighted crank, ported head etc etc puts out 208bhp but just wish i could work out the dam tacho issue!! the youtube vids (with the GSXR1100)gives you an idea what i do with the car!

- Harewood Hillclimb[/url] and

- Curborough Sprint new Class Record[/url] and when it goes wrong!!

- Harewood 27-8-06[/url]

 

[POWERHOUSE]

The tach signal wire from the ECU is a yellow wire with a blue tracer . . . did you try taking your signal from that wire?

 

[danemsteve]

yeah thats were i started! which makes the tacho read 5k at full throttle the coil route makes it read 2500rpm at full throttle! help!lease:

 

[Dirtanion1]

If the tach is a 8cylinder tach it should be set to half pulse. How high is the engine actualy idling at? A timing light or rpm light should be able to tell you this. If I were to hold my throttle at 3/4 it would rev to around 10000rpm. Most tach will take a single fire signal then times it by however many cylinders- some have a switch for 4,6,8 cylinders on the back.