TD_D mod journey. From stock to the 'bastardmobile'

[Td_d]

Well, tried the zeroed AVCS approach - turned out quite lumpy again - which I guess would be the need to completely redo the MAF scaling again - so I reverted to my latest map with the load comp and further massaged the compensation in some of the lower cells, and I have to admit it's really pretty close to right now (plus the additional comp has lowered the AFRs in the areas affected, and reduced knock down to -1.4 occasionally now - so I guess I can up it a little more). I have to admit the log and feel approach has worked better in fine-tuning than full on load comp calculations...

I would like to get further input on the intake AVCS issue - I did notice on the latest logs that at higher RPMS, they do track within 1-2 degrees. Makes me think that it's oil pressure related - at low loads and RPMs one is lower than the other, but at higher loads, they track correctly.

 

[HolyCrapItsFast]

I bet the log and tweak method is the way to do it. I am currently helping another guy at IWSTI on a similar issue but his is an 06 so the load comps are much easier to figure out and you only have one table to worry about. I have noticed that the excel file is good to get you started but you almost always have to go back to it to tweak it.

Yeah I dunno. It sounds like it could be oil related. Check to see if the screen filters are not clogged. That may not be an easy task though. You have to do an awful lot of wrenching to get to them. I would do some research first though. I heard that from 07 on they don't have them.

 

[Td_d]

There's conflicting info out there, but it looks like the 08's don't have the avcs screens any more...

 

[Td_d]

Looking at the right to left bank delta - anywhere between -8 and 20, those are some big swings... I know there is some slop / catch up between the two at times, but those are big numbers. If there's no filter, that leaves the solenoid I guess.

 

[HolyCrapItsFast]

Some how you need to confirm the oil pressure to each bank. I just don't know how to go about doing that. Or you could try switching the solenoids and see if the problem follows it.

 

[Td_d]

I've given the mechanic a shout to see his opinion - but I must say, looking closer at a couple of logs now, the differential between the banks on the intake seems to happen only on rapid increase or decrease of load - i.e. when the ECU would be moving between AVCS timing cells - and the trend seems to be that one bank lags behind the other (up or down) and then catches up - at worse 30 cells, and with the CAN logging which is 0.04 sec per log row, it might exagerate the effect? I know that some lag between the banks is normal - question is how much...

Must say with the latest Rom revision, car is driving very smoothly, top and bottom end. Getting frustrated waiting for the widebank - want to rock that upper MAF scale now!

I'd be keen to get some indicative Torque / HP figures - Fuji mentioned a virtual dyno or something similar? Question is can I get legit numbers without the wideband?

 

[Td_d]

Great - must give it a try - will google for a link.

George - since I'm waiting for the wideband, I'd like to try and tweak tip-in - I get the feeling that it needs to be increased - there's a 'shudder' when I change throttle angle, which makes me think that it might be leaning slightly on tip-in. How do I go about a) verifying, and b) calibrating it?

 

[HolyCrapItsFast]

Log A/F correction, Throttle Opening Angle, FBKC and A/F Sensor Ratio. When you take the log drive around town and use some abrupt throttle inputs. Go from a steady throttle input and affect a change. Do a couple runs and start with a 10% change in throttle delta, then 20% and all the way up to 100%. So essentially when you read the logs you want to focus on these areas where you affected the change in throttle delta and observe the trims during that change. The amount of trim divided by two is the amount of percent you add or subtract from the tip-in tables for the % of throttle delta applicable.

AFR should confirm if you really need more tip-in or not. When a change in throttle delta is observed you should see that your AFR is either the same or slightly richer than before the change. FBKC can also confirm this if you observe knock during the onset of throttle.

I'm not sure if you should use CAN to log or not. I would try it both ways and post them up if you could.

 

[Td_d]

Thanks! I had some ideas of using throttle delta and AFRs to try and spot problems (see, I have been paying attention ) - and it did look like there were a couple of areas - plus very minor knock (low down) associated. Will give that a shot...

On another note - I see you and Fuji are test driving LC and FFS - I'm so tempted - how does it feel?

 

[Td_d]

I've been eyeballing Tinywrex's site, $50 for a patch for my rom... quick way to fry what's left of my stock clutch :lol:

 

[Td_d]

Yes. Afr will not be accurate on graph or you can uncheck option. However, VD is made to graph wot. It uses calculated load, etc

Which version did you buy, out of interest?

 

[Td_d]

^ Cool avatar, very appropriate Fuji...

Can't tell you how gratifying it is to be able to rough and fine-tune the tune myself - managed to eliminate some knock today - the great thing is knowing exactly where to go, making the changes, and then seeing the results verified in the logs.

Downloaded virtual dyno (was confusing it with virtual dyno 2000, paid for) - now if only I could a) find a long level stretch of road; b) manage to get it clear enough to do a WOT pull in 3rd...

 

[Td_d]

Yeah, gotcha - already made sure (still stock 245 / 40 R18's)

 

[Td_d]

Yup - did exactly that, would be a pain to do it everytime - now to get the logs!

 

[Td_d]

Jeesh - not easy finding an open stretch, so managed to do a less than ideal WOT on the highway this afternoon on the way back from somewhere. If virtual dyno is to be believed, SAE base, but 1:1 correction factor (i.e. using the VD uncorrected, not dynojet or mustang setting), peak of 444hp and 373 lbft @ 6244 RPMs. The fact that power and torque peak at the same RPM makes me wonder... will need to do a couple more runs when it's nice and clear.

 

[Td_d]

Yeah - changed the tire size (245/40 R18 - gives a factor of 25.72) - graph is relatively even, off dip before peak though. I'm running meth and 100RON+ (95 AKI+), so it's possible, but I think more WOT runs are necessary (nevermind that I'm still waiting for the wideband to tune in WOT as well...)

This is with smoothing 3:

http://www.igotasti.com/vBforum/album.php?albumid=28&attachmentid=986

 

[Td_d]

Oh - and AFR (and boost) are not accurate - given that AFR is narrow band, so pegging at 11.25 and boost is still the standard MAP - whereas I know from the EBC that I'm peaking at 1.55bar.

 

[Td_d]

Just looking at the power curve I can tell you have some fueling issues with your tune at WOT. When you gat a wideband and set it up to log, there will be special settings in the VD program to get it to extract the right AFR for the graph, pretty much the program just needs to know what the column is named.

Could you elaborate? As in the way it's graphing, or the actual power delivery? It's well rich, I know that much...

 

[Td_d]

Yup - it's a Dom3XTR - should be holding power straight through, not dropping off after 6200.

 

[Td_d]

It's quite frustrating waiting for the wideband - we made so much progress, and playing with the WOT MAF scaling blind... well, let's say it's not a good idea. Spot on - it's very rich up front (popping spectacularly as I do a quick gear at WOT). I guess I could slowly start dropping the earlier (4000-5000 RPM) MAF scale, at .05 - 1% at a time, and log. A little hair-raising though.