cops and dyna ,but where to put the tach?

[pumacorp]

I have the dyna 3000 with the cops,,but ive been trying to figure out where to run the tach line..I wont give me accurate readings on the coil leads so where else can I grab one from?

Does the dyna have a tach line?

 

[naughtyG]

You DID put resistors in series with the COPs right?

If not, you WILL fry your Dyna3k!

 

[RagingMain]

You DID put resistors in series with the COPs right?

If not, you WILL fry your Dyna3k!

Yeah you will need 1-1.2 ohm 15-20 watt resistors inline with each COP or your Dyna will become a paper weight.

I take it you have an aftermarket Tach???
Or are you trying to hook your Dyna up to a tach signal???

 

[pumacorp]

aftermarket tach and yes I did use resistors..1.5 ohms cause most of the denso cops are 1.4 and dyno needs to see 3 ohms so im good..the line going into the coils wont read steady at all so i need a better more stable source...

 

[RagingMain]

Have you tried the negative wire of the COPS.
That is where my Dyno guy hooks up with his inductive pickup

 

[Thevmaxrider]

For my aftermarket tach I used the stock tach feed wire and pulled power from the running lights. Most competition tachs will not be steady at anything under 2k rpm as they are unbuffered.

 

[pumacorp]

tried feed off cops,,,,doesnt work right,,,,,,tried tach feed,,doesnt work,,,running out of options...thought there might be a feed off the dyna 3000..

 

[KJShover]

what brand and model of tach is it?

 

[Thevmaxrider]

Is it reading 50% of actual RPM? If so you need to find out how to set it up as a 2cyl engine......

 

[pumacorp]

no has nothing to do with the tach setting im ok there....Just very irratic,,jumps all over the place ....Its an aftermarket tach by trail tech ....Its just not a steady signal its needs a buffer like a resistor ,,but not sure which resistor to tun...I guess ill experiment..I figured there might be a lead off the dyna,,but so far dynatek hasnt contacted me about it..

 

[Thevmaxrider]

My Autometer Pro Cycle tach bounces all over the place under 2k rpm, but once the engine revs it is very accurate. Good luck and let us know how it turns out!!

 

[pumacorp]

so far no good..I tried a few different combos on the resistors with no luck at all...Next up I will try a ferrite magnet to see if I kill line noise (EMI) that may help..

I know that they do sell cop tach adapters for cars that ive used in the past,,but not sure they will work and they are pricey..

the next step after the ferrite I will try an inline noise filter..
I will keep trying til I find a solution so the next guy on here doesnt pull his hair out..
Oh by the way Dynatek doesnt know if they have a tach line lol...WTF ,,,,they said its direct plug in so they dont know...Come on they dont have a wiring diagram thats soooo stupid!

I will try to hook it to my vboost signal as I do not have vboost anyway....that might work..

 

[pumacorp]

problem solved...After trying a few different ways to filter the signal..I tried something a little strange that I thought might work..I took shielded wire,,put it over the tach hot lead...I connected my tach to the shield instead of the wire,,,it works perfect...No jumps and is accurate at hi and low rpm...


Dont get me wrong it was a longshot,,but it works by dampening the signal .kind of like what you would do if u wrapped the lead around the HT wire with same result...