RED=Engine Speed Update Rate=3(Medium)
Green=Throttle Update Rate=3(Medium)
Purple=Engine Load Update Rate=3(Medium)
Yellow=Knock Raw Voltage Update Rate=0(Fastest)

Do you see the strangeness?? I think I know what caused this.. I don't want to point it out because I don't want hinder everyones opinions on what caused this. Thanks for ideas to what this Anomaly is. Thats what i'm calling it an Anomaly.

If you guys need anymore info or anything please let me know. I would like some suggestions before I go on another Electrical overhall

 

Assuming a b series?
Are you using knock ctrl?
Can u feel it acting up?

Even the wavyness of the rpm is making me point to some type of voltage surge?

 

Yes built Turbo B18c, the highest the rpms got was 4000rpm. I was thinking it could be noise(EMI/RFI). But, now i'm wondering if its not maybe just the Brand new FX725 Clutch causing this. I looked back at the First log I took when I first started the Car and revved it at 0mph I didn't see that scwiggle.

I have done 2 logs while in motion and they both have this od wave when the rpms drop. It appears timing is moving with this rpm wave. Has anyone here done a log using a good Twin Disc? Last night I thought for sure EMI now i'm beginning to think because that clutch engauges immediatly is the cause. But, idk yeat.

 

I have logged with twin disc. No squiggle here.

Maybe try revving in neutral while rolling. Looks for squiggle in that log.

It could be the clutch during disengagement just making the engine shimmy and causing th pickup signal oscillation... I personally have not experienced this but if you were shifting gears(no vss logged), in that log then voila.

 

It's happening during Engagement. You see the rpm fall when I disengage the Clutch and then the scwiggle happens during engagement, when the rpm begins to come back up in the next gear.

 

Here another log I took today. I was trying to be softer with my shifting.
You can see timing following rpm. I'm have a hard time convincing myself this is caused by Electrical Interference. I would imagine if it was interference it would be random??
In this log you can see it only happens when I get back on the throttle. At the end you see the scwiggle and the throttle was at zero the entire time, this was do to a downshift/clutch engagement.

I have dumped over 30k into this build and i'v done every bit of the work. This Tuning portion of the project is proving to be a challenge and you guys are the only help i'v got, so thanks for responding.

FYI BLUE=Vehicle Speed

 

That ign change during oscillation would make me uncomfortable, with concern of it happening at higher loads when shifting hard.

By chance is this car fitted with solid mounts?

 

It has Avid Mounts/Polyurethane bushings in the mounts and all around the Car has new Poly Bushings. So NO Solid Mounts.

Knock Control was active at the time of these logs however, the Knock Cal Table is set to high to make a difference. Parameters showed it make no change to Fuel or Ign.

I don't know if this long is normal looking for this type of setup or if it is not looking good. I don't like that rpm scwiggle and Knock jumps pretty high at low rpms. So please keep the opinions coming.

I'm going to tare into the Car today and change some things and then hopefully tomorrow I can get an "Internal Datalog".

 

Its def the clutch. As long as it doesn't happen at wot you are fine. If it causes issues, you can tune around it. Doesnt really solve much but would work.