...or put another way
page 53 of the TTS manual shows an example of VE graph before and after adjusting the CDE (ok, EGR, even if we aren't actually recirculating exhaust gasses).

The value is reduced to "lower the peak VE values and flatten out the table in part throttle regions" - the main smoothing I see looks as if it is above the 60kpa trend line, apart from maybe the 80-100% tps. To do that the change to the tables ranged from 30% or so at low revs to 60% at high revs.

I guess what I'm wondering is where did they get the numbers from in their example? There must be a calculation somewhere if TTS can put it into their VTune, no?

 

tagged

 

Are you sure the break point for the CDE tables in vision is 60? There are several break points that are different with TTS than the other tuners. Is it set up correctly in the calibration or is it any turned on in the level of calibration you are dealing with. I have seen tables in the vision cal that is there in the tables but has no affect because they don't actually change the calibration. The delta change of 27 and 31 should of changed something with the VE table.

 

Good question, the TTS is the only place that offers anything on CDE/EGR tuning so I "assumed" 60kpa.

The map I started with was for a calibration 358 softail, same as stock, although I know what you mean about the PV and tables that aren't used, you see that if you try to compare two dissimilar configurations for example.

CDE tables are definitely in the stock map so I expect them to be used.

I'll run another tune today

 

Here's a thought...

PV tuning advice is to raise the minimum MAP to 35 or 40 so that no samples with MAP less than that are collected and used in the autotune ...I wonder if that's right?

 

Gordon61, from what I have seen and used the cde/egr tables work the same way. However the tts has a much larger range. If you look at a tts map, DAC617-14 for example, the egr range goes from 2.392 to .264 as a low. When I used the the tts vt2 software it changed the egr tables sometimes 50%, in some cells, and then 40% on the next couple of tunes. On the winpv software it only has a range of 0-256. the info box states that that ranges roughly equates to a total of 2% change. The cde tables do work, its time consuming. I was able to smooth out a small dip in my tune.

As far as limiting the ve tuning range I believe it was mentioned that 30kpa was a good minimum when using a map base tune, I don't know about a tps style tune. Under 30kpa is decel. From my experience, tuning on the street, throttle control in that area is critical. Back off the throttle to quickly can lead to a big hole in the ve map, as it shuts the fuel off to the injectors. On a dyno it is probably a lot easier.

 

Ah, now I didn't realise that. I'll have another go at super smooth in the area where I am getting my dip.

In regard to setting a minimum MAP for tuning, the PV sticky thread and a couple of others have suggested both 35 and 40. No one has actually said why other than "so as not to collect spurious data" but I think you hit the nail on the head ...what we actually want to discount is possibly the bulk of any decel data. That means you need to have a look at what your idle MAP is ...given different cam timing and overlap tend to change this. Especially if the map doesn't really take into account cam timing as Ed Ramberger pointed out earlier

Mine was up at 42 (at sea level) for example, which was why I set the min MAP for autotune to 40.

 

If you compare the WinPV maps with the stock you will find that TTS and PV and FP3 for that matter are all the same ...they just show the number differently

e.g. 200 in WinPV is the same as 2.00 in TTS. The FP3 only accepts x.yy i.e. 2 decimal places. So, same number in the map, but displayed by software differently

Given the little change these tables make to the overall calculation, 2 decimal places is probably more than enough.

 

So here's a real world example ...i.e. mine

Starting VE table tuned to within 1%




So I was hoping to raise the dip in the 0-5% TPS so I added 20% to the CDE as follows



What I got though, was the following change which (other than keep sucking and seeing) I'm not sure I spot any kind of rhyme nor reason to what it did



Am I wrong thinking I can raise the dip, or what kind of CDE values would you try too smooth out that starting VE table?

cheers

 

So, having put PV and cams and MAP at idle to bed and getting back to CDE, any thoughts here guys or am I still sucking it and seeing?