Spark angle in datalog doesnt match map.

[Deuce8ernerozero]

When I mash the gas at wot from idle i go up into a block of 10s on my spark map. At that point the car stutters bad. At first I thought it was a distributor phasing problem so I changed it. It's still there. A quick look at a datalog showed my spark advance goes around 7 in my 10s. And, the whole map is offset a bit from what its spitting out and showing on the datalog. I'm not getting full advance. It's strange because when idle advance kicks in I'm at 10 degrees like I set it. Sometimes, when I rev the car hard from idle it will stutter and if I have a timing light connected it wont flash while its stuttering. I will post a tune and datalog of it happening.

[arran]

Is sync loss count incrementing?

[Deuce8ernerozero]

No. And, I'm running megasquirt and spark codebase with a distributor without a missing tooth. No resets.

[slow_hemi6]

It seems odd to me that you would have -9 for cranking timing and -9 in your rev limit. I am not even sure if ATDC figures are possible with MSNS and timed return. Your IAT/CLT related igniton settings seem a bit odd as well. CLT setpoint is normally lower than IAT setpoint and having IAT enabled from 0 kpa is also weird.

[Deuce8ernerozero]

It starts. But, I am gonna change these values to more appropriate values. Matter of fact, I'm cutting iat/cts based advance off. Also, no boost.

[Deuce8ernerozero]

Ok. The initial problem is fixed But, I still have hesitation. here is another .msq and datalog. Is my acceleration enrichment going negative? Also, I've noticed map de stays on pretty much all the time.

[slow_hemi6]

I wouldn't be too concerned about map because you have it turned off by running tps based. A lot of your bog will be the fact that you remove timing down to 10 degrees exactly when you need to be ramping it up. Bring up spark angle on your log and compare the rpm hesitation to the period of 10degree timing. Direct correlation there.

[Deuce8ernerozero]

I made the spark map exactly word for word from my factory service manual specs on the distributor. I guess I can just put 27 degrees all the way across the wot section... hmmm

[Deuce8ernerozero]

It pulls through the miss and revs quickly but pings/knocks loudly. I'll try half that and do some ae adjustment.

[slow_hemi6]

You never mentioned what type of engine, if it is standard or modified or what compression ratio it has. Those would be good to know.

[Deuce8ernerozero]

Nissan l28e stock 8.3:1 c.r.

[Deuce8ernerozero]

I got my hands on a timing light.
I have no spark during these hesitations.
It drops out completely. no flashing at all.
car runs great except for the cut out.