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I keep uncovering things from DA3 that improve the way the car drives with this Miniram. It's astounding how so much of the DA3 (a completely different ECM) ports over to 8D and runs so much better. The base code must be very very similar.
In this instance, the tables Slow O2 Filter Coefficient vs Airflow and the O2 Integrator Delay vs Airflow.
Here's 8D (top) vs DA3 (bottom). Granted the DA3 is using two O2 sensors, so i just grabbed one side. Also the number divisions in the table is different, so I just interpolated between values to fully populate into 8D.
Not exactly sure why it's running better... I don't know for sure what these tables do. Also not even sure how to describe in words how it actually is better... but the seat of the pants feel vs my foot on the throttle... it just feels "crisper" and more responsive. Like somehow the transition out of AE fueling into normal fueling feels more crisp... if that makes sense.
Everytime I think I've optimized it, it gets a little better when I find something new... lol
Actually a hybrid between the DA2 BAFL Corvette and the 8D AXCN Corvette. I found that the L98 was too conservative at high load and the LT1 was too conservative in the low-mid load. So I essentially merged the two into a hybrid table and it works very well.
Absolutely agree, and great work by the way. I remember when I siamesed the Tuned Port Injection system years back, the known bins were useless to work with. Reviewed $EE, started changing things to compensate and it made a huge difference in how the car felt overall.
I travel for work on occasion and have to rent cars... so when I drive the late model cars, there's a part throttle feel to it that's just super crisp and nimble (not sure how else to describe it).
And I had always thought that there has to be a way to get my SBC to feel like that... I figured that an engine is an engine for the most part (notwithstanding the overhead cams, and all the other modern tech)... but that it mostly had to do with the tuning.
Turns out I was right, as I've finally gotten to the point where my throttle feels just like those late models.
It is always intriguing to me seeing such high SA values as found in the LT1s and L98s and similar. If I didn't have so many false knock issues I would be a lot more inclined to up the ante on my SA. I've taken a conservative approach in that regard solely due to the false knock.
Have you read through some of the recent threads on false knock? There are ways you can determine one way or the other.
Believe me, the added timing is well worth the effort.
As a reference, i run 9.8:1 compression with a cam at 215@.050 with a 114 LSA, on 91 octane gas. I'll get about a 1 to 1.5 retard kicking in every now and then, but I'm ok with it since I know the ECM is taking care of it and I never hear any audible pinging.
Have you read through some of the recent threads on false knock? There are ways you can determine one way or the other.
Believe me, the added timing is well worth the effort.
As a reference, i run 9.8:1 compression with a cam at 215@.050 with a 114 LSA, on 91 octane gas. I'll get about a 1 to 1.5 retard kicking in every now and then, but I'm ok with it since I know the ECM is taking care of it and I never hear any audible pinging.
I sure have. Me and you discussed it some in one of your threads. I went with the same delco sensor you put in as well. Torqued to spec. I am fairly confident a majority of mine that is being picked up is driveline noise. I still have a pretty mean clunk in my umi torque. And fairly confident I have some input shaft bushing/throw out bearing noise starting.
I see a lot of counts pop up all at once in areas I wouldn't expect to get counts or on shifts. For example I doubt it is true knock at 1600rpm 50 map with 27* spark...
I wish I had just gone straight to running a 90* fitting with some thread tape to quiet it down some.
I sure have. Me and you discussed it some in one of your threads. I went with the same delco sensor you put in as well. Torqued to spec. I am fairly confident a majority of mine that is being picked up is driveline noise. I still have a pretty mean clunk in my umi torque. And fairly confident I have some input shaft bushing/throw out bearing noise starting.
I see a lot of counts pop up all at once in areas I wouldn't expect to get counts or on shifts. For example I doubt it is true knock at 1600rpm 50 map with 27* spark...
I wish I had just gone straight to running a 90* fitting with some thread tape to quiet it down some.
My main point of reference on my more recent "false knock" effort was a previous situation years ago where I was attempting to run ~10.1:1 compression... such that the knocking became very audible when the ECM ran out of knock retard allocation in the tune.
During my diagnostics, (since I knew what to listen for) I had turned off the knock retard and was gently getting into the throttle to see if I could hear anything. When I didn't, I would get into a little bit harder, and then harder, etc... And when nothing manifested, that was a big data point that it was false knock. And, like you, I was getting knock retard in areas that made zero sense.
I just think these modified engines simply generate a lot of "noise" with roller rockers and cams with more aggressive ramp rates, headers, etc, etc... it ends up playing games with the knock sensor.
Yeah, I have been scared of knock for years now too after I had detonation ruin some pistons when I was 19 with this car. I blame it fully on lack of experience and knowledge of what I was doing...but still makes me fear going too far with SA. I think I would struggle to hear the pinging too between loud exhaust system and having pretty bad tinnitus in my ears.
Spark plugs can show indications of detonation. That's also something I looked at. If you google the subject, you can find what I'm referring to (unless you've done that already).
Yesterday, 02:31 PM
