Help Debugging the High Load OTS tune

[mituc]

The KR at WOT is now eliminated, I don't think I even saw any. However, I'm running too rich now with the stock targets so I'm going to see after I'll test with these new values.
The FRP still jumps too high way over the limits (going up to 1830-1850PSI which I guess is almost matching the specs of the FR relief valve), and now I get that hesitation when shifting from 3rd to 4th under hard acceleration. I feel like shooting in the dark TBH and at this point at this late hour I'm close to giving up and returning to my old tune.

I made the MAF CAL even better but not sure about the other params, especially the BCS table which seems to be the reason why I don't get any higher boost values (however, the load still goes up to 2.0something). Changelog:

* 1.11
- OL PT AFR targets reverted to the HL map;
- OL WOT AFR Targets placed in between the stock and HL values (AVERAGE(STOCK, STOCK, HL) - so closer to stock but leaner);
- New MAF CAL;
- FRP overall limit and targets set to stock.

[manselainen]

Eh, not trying to argue, but in pulls file, at 390 secs, boost is spiking and fp drops very low, MAP remains at 2 bar. Can't be motor braking. Maybe log APP instead of MAF Volts or sthng...

[mituc]

No, I'm glad that you insist, really. I'll look at the on-board camera tomorrow and make sure this is what I was doing.
About the load spiking at that moment... I noticed that it uses to do that. Is that gear shift change smoothing (or the no-lift shift support) that does that? I noticed that several times on the VT logs I took and in the dashdaq logs as well. First I thought that the logging devices still see the load up high because of some communication delay but now I'm thinking that this may be the reason why when shifting from 3rd to 4th I get that stutter and power loss. That doesn't happen when I shift from 4th to 5th (or I don't notice it because of the taller 5th gear), and doesn't happen if I go WOT in 4th at 3000rpm-ish up to the red line.

I did a few more tests today, my new MAF cal is perfect (however, considering that the values curve is not smooth I'll probably have to clean my MAF again, as I did this one year and a half ago) but the v1.10 pig - err, what pig?!, elephant rich tune seemed to be the best I had till date (better than hypertech!!)! The engine sound during WOT pulls was good, hardly got any KR, and so on. But that 4th gear stutter spoiled it. I'll work on that a bit more, reduce the FRP targets and limits but still set them at like 1690PSI (1670stock) as with the today MAP with stock FRP targets and limit I was getting FRP's just below 1750PSI which is fine but 10-20PSI more will never hurt as long as (I think) my pump can handle that.

The roads here are now dirty (they threw sand on them last night) and loosing traction anywhere any time, so today I flashed hypertech back just to be safe over the winter (as there still is a chance for my pump not to be able to keep up, as you suggest) and in February or maybe March I'll get some gold KMD's from QAS.

I'm also waiting to see how the tables will look like for that high-load map on a MS3 with downpipe (Steve was saying something about releasing that around the same date of the stock MS3 High Load map dyno session on Jan 5) and then I'll tweak mine.

[Steve @ VersaTune]

I sent you my working copy of the Base 93/98 high flow exhaust tune to your email. Copy the BCS DC Base and Requested Load Multiplier accel/decel tables to help with the boost spike when shifting.

If you didn't get it, I'll post it here.

[mituc]

I didn't happen to get a Christmas present, but I've got one for the New Year! Thanks Steve!
So yes, I've got it and now I'm eager to do more tests which will have to wait because of the weather conditions.

Later edit: Oh man, I was pretty close in so many areas in that BCS DC table! But that's what happens when you're guessing and don't have enough knowledge at least to test and gather the right logging data and eventually be lucky enough to guess only a small part of the picture!

[Steve @ VersaTune]

You'll want to fine tune that BCS DC table with your actual log data, but that should help.

[manselainen]

I also had hesitation when changing from 3rd onto 4th with stock HPFP. Pressure went down to 1000 psi. After pump internals upgrade it has been OK.

[mituc]

Ok, you were right, I accelerated after that gear change too. Maybe that's what's causing the hesitation when shifting from 3rd to 4th, but now I wonder why doesn't that happen with the other tune and the FRP is always above 1650? What's triggering this event? The higher load targets?

Later edit: most probably it's the load targets. I decided to use the Base map per gear load targets instead while leaving all the changes I did so far as they are (MAF CAL, AFR targets, absolute load limits, and so on) and using Steve's BCS and accel/decel tables. I'll see how this works after the holidays. If that's going to work I'm going to start increasing load by 0.02 at a time and keep an eye on the FRP. I'm also going to order the KDM internals from quantumautosport.

Happy New Year everybody and thank you for your support!

[mituc]

I also had hesitation when changing from 3rd onto 4th with stock HPFP. Pressure went down to 1000 psi. After pump internals upgrade it has been OK.

I ordered the Autotech internals today, they should be here in 2-3 weeks or so and I'll put them on at the dealer when I'll do the spring oil change first week in March.

However, the original high load map has the FRP limit set to about 1799.something PSI, and the FRP targets for load values higher than 1.8 and RPM>4k (IIRC) were also set to 1799PSI.
Since even on the stock tune, stock car, no mods at all, the FRP goes up to 1750 sometimes (90PSI more) while the limit and targets are set no higher than 1670PSI, if the new limits are set close to 1800 while the relief valve starts recirculating at 130BAR IIRC (meaning around/less than 1890PSI), isn't it possible that with these commanded FRP values the actual FRP (1799 + more or less than 90PSI) to go above the limit of the relief valve and thus making the actual FRP to drop around 1000-1200PSI just like it was happening in my case?

This is the reason why I started to lower the commanded FRP in the more recent versions of my custom high load map, but now I thought I should ask, maybe someone with more knowledge has an idea, maybe there's something else wrong and adding the Autotech internals will not fix it, or make it even worse.

This still concerns me because:
1. my pump can meet the requested fuel pressure values and this can be seen in the logs;
2. my relief valve doesn't seem to have any problem as the FRP stays steady at 1600+ or even 1700+ with the stock tune or hypertech.

[skiptownmcat]

You may be on to something there, but I was under the impression the frv would only release under sustained pressure above 1885 psi (could be wrong though)