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Ive spent the last 2 weekends tuning a mates car. Id love for everyone to look over it and see what improvements could be made.
It was tuned with NVRAM and wide band sensor fitted, with 12P V1.11.
It was my first go at tuning after years of reading all about it. But i did have a head start i guess copying stuff from the DB bin.

Engine is a Holden 308 stroked to 355, Crow solid cam specs are advertised 290in 310exh 109lc (from memory, yes its a decent cam)
Compression measured at 11.2 (zero deck 3cc pistons and shaved head), COME twin throttle intake, ported heads (standard valves) and good exhaust extractors twin cat and an MSD igntion.

It previously ran a single plane carby style intake and had been well tuned in $DB code. But then had the intake change and needed some work.

Ive attached the latest bin and a log. The car drives very smooth as it is.
Everytime i smooth out the VE map it doesnt drive the same, guess it comes down to experience and practice.

Look forward to any feedback!

Certainly not the easiest combo to start on and overall it looks like its running pretty well! AE might have some fine tuning and a few areas could have some minor fuel adjustments.

Nothing in the bin really stands out as an odd change, good job

I haven't had a look at the log yet, but I did find the same issue when I tuned my first & only time so far with $12p.
After I adjusted the VE from wideband log & smoothed the VE out it created dull spots when driving, I never did figure it out I just left it with what felt best & let the trims tidy it up!
It was all the normal mod's to a 304 with stock injectors (which were hitting over 80% duty cycle) & I think a 286 cam from memory.

From what VL's said looks pretty good!

I don't think smoothing the VE or spark will result the best performance in all cases. I think that there will be areas in the physical VE of the engine where it does spike likely from intake/exhaust resonance and such other factors, so naturally the VE table should be dialed in to give it what it wants.

I noticed the factory VE and spark tables are spiky in certain areas and it certainly doesn't feel spiky when driving. I reckon a little smoothing is ok, but not ignoring spiky VE areas that keep showing up with the WB.

With the previous manifold and tune tge ve map was smooth, but I never got the wideband on that.
The next logs I get I will look at the monitors more closely for adjustments. Ive been using histograms to get it this close.
Most of the lumpy bits are in the 14.7 area so might even put the narrow band back in and wstch tge BLM's.

yeah but if it was smooth and rich, you'd never know, because it doesn't have the hesitation or stumble like a lean spike would!

its all a game really, but if its smooth to drive with the spikes I agree with vlad01, leave them there!

ill be interested to see how the WOT looks when fully tuned. in that log I dont see any WOT runs from low RPM where you will encoutner the spike I did.


heres my early tune to suit a 355 with come racing manifold. note the massive spike at low rpm. believe it or not... the wideband is a dead straight line with that mountain range of a 100kpa VE.

I used to get similar results with the vk efi manifold naturally aspirated!

I think im going to have to try some message 6 commands for the top end. Watching the wide band looks good and logs are ok but I think its a but slow for full thtottle runs nothing lines up real good and revs don't max out, rpm slope on gear change is way out with TPS.

I have a power run from an earlier version of this tune. Does this sound right are the messsge 6 commonly used?
This is obviously road tuning no dyno.

i use message 6 logging in my race car, i can get 32hz logging speed, with the full message its only about 10-15hz so definately going to pick up more points with M6