Analyze this data log

pwrful4

Member
First DH log, I think I recorded a 3rd an 4th gear run here. 09 MS3 with a CPE Nano.

What gear do most folks do their logs in? I noticed I got a knock of 2, anything to be worried about there? Any help in gathering the right info and taking good logs would be appreciated.

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Everything looks pretty normal minus that knock retard. AFRs are on the rich side, but that's normal. What octane of fuel are you running? Any other mods? Some knock retard is noticed even on a stock vehicle, so I wouldn't be TOO worried about it.
 
Try logging fuel pressure direct injection as well. Doubt it is an issue with that AFR and just an intake but may want to make sure, some people have had issues.
 
Knock looks normal. My brothers stock with 1000miles on it was knocking around 2 on full throttle runs. It really boggles my mind that Mazda didn't fix this before releasing.

On an MS3, I'd say keep your eye on both gears when logging/tunig.

And as for parameters...
IMO
1. RPM
2. Boost
3. AFR
4. Knock Retard
5. Boost Air Temps / Fuel Pressure

The Boost air temps have a HUGE influence on KR.
 
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Everything looks goods, but what gear shifts are we looking at? 3rd-4th-5th? Because the knock in 4th I believe is a little high @ 2.1 for just having an Intake, but not dangerous enough to blow the motor like say 7.0 or so. I have a SRI, BPV ,and a CBE and I don't even see knock over 0.7 and I'm on 91 octane.

Start datalogging fuel pressure along with the knock retard and see if it drops below 1000psi @ WOT. If it does, that mean your fuel pump is on it way to dying. At idle after the car has warmed up, Fuel Press should be around 420-450 psi
 
Another log with fuel pressure, 4th gear run. Still seeing a little bit of knock, sure don't like the rich AFR. I bought an AP today will try the Stage 1+SF 93 Octane map. I'm only running the CP-E Nano and think this will work.

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From what I can see, everything looks okay. But from looking at both graphs, you are getting the peak of your knock around 4800rpms. Might be a bad batch of gas.
 
I am a Aerospace Propulsion Journeyman working on Pratt-Whitney F100-220/229 Jet eninges and perform leak and operational checks in Test Cell

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Good on ya! Best engines out there. Flew Strike Eagles at SJ with the 220's. What are your thoughts on using the AP map made for the Cobb SRI with my CP-E Nano SRI?

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