COPS - Dwell Setting, location..Please Confirm
 

Hi Guys

There are many threads here about setting the DWELL to 2.5ms and I presumed it would be easy to do.

We are just about to fire the car up and I now see there are a few options of dwell settings.

I presume the correct setting location is...

Basic setup/more ignition options/ Maximum Dwell Duration

Can someone please confirm or redirect me if I am wrong please?

EDIT: there is a plain "dwell" setting but it is greyed out and unadjustable...

I also note there is an option to change from single coil to Coil on Plugs....no one seems to mention changing this setting in all the threads I have looked up..???

This is what mine looks like in ms3 for TOYOTA COPS. Don't mind the trigger info, I'm using a 36-1 wheel running batch.

https://www.miataturbo.net/attachmen...-smurfette-jpg

Thanks for the reply Psyber. unfortunately your page is totally different to mine, must be a MS2 v MS3 thing.

For future reference...to anyone looking as I did.

The dwell setting for COPS is where I described it above....I have set my Maximum Dwell Duration to 2.2 ms

I was also told to reduce the Cranking Dwell down to around 3ms.

There is a setting to change to Coil on Plug but have been since told to leave it on the standard setting.

Car started and ran perfectly , so I'm pretty pleased.


BUT I have a small rant!!!

Why is everything so vague when it comes to megasquirt!!!

It is a lot harder than we are lead to believe, in that there are so many versions, and what works for one is different for another etc. It's such a great product but friggin hard to get straight info about. :vash:

it's the normal dwell number. You should put in there whatever your coil's dwell time needs to be at 12v. Then you should tune the battery dwell table according to how you coil's dwell time changes vs. battery voltage.

toyota cops people should end up with 1.9-2.1 in that field.

Brain, could you elaborate on the battery dwell table tune? I'm having what sounds like intermittant misfire issues at high rpm, but am not finding any sync errors and have tried sparkplug with .025-.032" gap. I've been stumped and wonder if the voltage drop could be effecting the cops in any other way.

gap with toyota cops should be stock--like .040-.045".

I've posted the battery dwell table years ago, JasonC SBB measured the dwell curve of the cops way back when, and I configured the curve based on his finding.

I'm going to go out on a limb and suggest the miss is not cops related but something else in the tune.

Oh wow. Thanks for the response. 0.04" will still fire at 20psi? I'll regap and check again

That's what I was running on my car. After ~3000-4000 miles it would start to break up a little. I'd throw in a new set of BKR7E's and it'd be good again.

it shouldnt break up, up to about 25psi or so at that gap.

way more efficent when opened up, and strong enough to deliver.

So considering that...and me being at 25-26 psi, is my .032 appropriately gapped?

Thought I was having issues a while back while under full boost and adjusted from the original .040.

if that solved it, then sure.

Gapped to 0.040" and it feels smoother in mid range, but again it has a little stutter at 6. I am truly stumped. Brain, can I rent your mind later this month when I move back to Fairfax?

sure.