Jet, balancing the front to rear is almost impossible, without getting head work done, and a disk type of exhaust system. To flatten out the ve tables you would use the charge dilution tables. It works to a degree, I believe it is a max of 2% in either direction. It is only going to work from idle to 60 kpa, maybe 65 kpa. It is time consuming. I am doing some experimenting with it. After each adjustment in the charge dilution, you have go out and auto tune again. Now from what I've read, this adjustment basically changes the the math formula for the cells in its range and how they are read. The more balanced the ve tables are the easier it is for the ecm to deliver a more constant performance. The less hunting (ve values) and adjustments the ecm has to do the more smoother the engine will run.

This is my understanding of it, if I am wrong I hope Jamie will chime in and correct me.

 

Wmitz- You bring up some good area of discussion. I had read something to that same effect on CD tables in another forum (auto related though)- Still a lot I don't know though due to lack of HD-specific information resources and valid experienced information. I've also read there are some fueling imbalances F/R present due to the stock HD intake runner design.

For me, gaining an advanced understanding of tuning the HD EFI system has been difficult. Main issue is most all publicly available data and discussion on Delphi tuning is in the automotive forums. Nothing really exists in general on HD Delphi tuning, best practices, breakdowns of what areas of tables to focus on for optimizing fuel, timing, and in depth discussions like tuning CD tables and effect on VE. I've been grateful for the knowledge I've been able to obtain thus far thanks to our forum sponsor and those of you more experienced tuning experts here I've had the pleasure of connecting with.

Lets take Jamie's last post on correctly using Auto Tune and preventing changes in the decel area, mention of fuel transients, wall wetting. Good stuff to know yet not common info to find and discuss on.

Lets take the PE settings for another example- In the automotive world, PE (Power Enrichment) is used extensively in the fully available Delphi "PE vs RPM" ratio tables. This table is calculated in equivalence ratio units, the inverse of lambda. it provides optimal A/F ratio for optimal power under heavier loads. This added function optimizes both economy and top performance on a given vehicle.
(ref: http://www.musclecardiy.com/performa...-and-examples/)

In the HD version, we get a stripped down bit of PE settings that are marginally useful- but could be useful to some degree if it were better understood how PE works and how we might be able to leverage it. Most everyone I mention PE to simply says, "I don't use it, turn it off, does nothing, etc". Usually the answer is based on not really knowing what it does, and good luck finding any HD-related tuning info on the web about using it.
Most don't know that fueling changes are delayed by the ECM when coming through the normal VE / AFR path. There is an inherent delay in fuel when going from say an economical 14.3 cruise cell to WOT and calling for a richer 12.8 cell. That can cause ping initially due to immediate load, timing cell value, and ECM's transition delay in delivering richer fuel. What the PE function does is provide immediate and non-delayed richer fuel delivery based on its enabled settings - e.g. going to 80% or greater TP, at 3200 rpm and greater.

I've tested the effects of enabling PE to some degree while going through my own tune file iterations over the past year- There is benefit to using it properly. Setting a bit of advanced timing in the 90-100 columns, I can induce ping going from cruise to WOT in 3rd around 3k rpm and relying only on normal ECM operations for providing richer fuel when hitting WOT. When I turn back on PE and set it properly, hitting same WOT throttle transition as previous there is no ping. So when I am not on heavy throttle (less than 80% TP AND under 3k rpm), I am following the normal path of the VE / AFR tables. When I exceed both 80% TP AND am over 3200 rpm, PE kicks in for immediate fuel delivery, I can run more timing advance at the same load, AFR without ping. Although I'd find this more useful if the PE's TP parameter were MAP based or ratio based instead, or if we did away with MAP based tuning altogether in favor of MAF .

My point of all this is, we really should have a dedicated "Harley Delphi Tuning Information Thread" for consolidating in depth tuning discussions and central repository of data. Someplace for experts, average and novice alike to discuss methods, details and what works / what does not in regards to tuning different parameters of the system (regardless of tuning product used). Particularly areas that are not commonly discussed such as how to optimize spark timing tables, DE, PE, CD, AE, etc. - That might be another good sponsor thread for FM, mainly because we know they are one of the subject experts in this area. - just a thought.

 

LA Dog, yeah that decel tuning tip was great. My bike idles at 31-34 kph, so I set the min to 25 kpa. I wonder if you can use say 28 kpa as a min, or do you have to stay within the kpa structure. There a lot of things with the Delphi system that are buried that we don't have access to. Probably to keep us from really screwing things up, lol. I used TTS for the 3 yrs before switching over on this bike. The can-bus system on the new bikes is a lot quicker for gathering data. If you ever get a chance look at some of the TTS ve tables for the 14's & up. They are pretty flat which make for a super smooth engine. I have always kept the PE enabled, never really played with it. I asked Jamie about upping some of the timing in some power areas. He said I could try, but, you might not get a ping, but the ECM would probably pull timing as a result in minor detonation.

 

Wmitz- yes all interesting questions. sort of seems like a lot of us are being pioneers with looking into these areas of the system and how to better use them. It is too bad that more of the system is not exposed. it would give us a lot better tuning options.

Check that link out in my last post- it covers a very interesting method of determining optimal timing using the spark knock detection system and data logging to your advantage. makes some sense to me and I'm going to try a few experiments along those lines.

From what I read on PE in a different HD forum, the consensus was to enable PE at 2600 rpm and say 90 TP. That makes sense because no one is whacking WOT at 4800-5000 rpm (default settings), you're usually whacking WOT at the upper 2k rpms.

The way we get PE explained to us is that it's there primarily to protect the engine from heat. But that is not PE's intended purpose or design within the Delphi system from wht I've read on it. If that were the case it would have been called "EP" (Engine Protection) instead of "PE" (Power Enrichment). ;p

 

Wmitz / Dog: you've provided meat to chew on for sure.
Your referencing the HD intake system design issues is accurate in my opinion. If I understand correctly, design changes were made around the '11 models which proved to degenerate those flaws further. Let alone manufacturing tolerances that introduce negative factors.

It is very difficult to ferret out definitive cause/effect descriptions of many of the Delphi parameters to which we do have access; I suspect part of that is because there are so many of which there is no to very limited access that can be destructively altered by the misapplication of changes to the parameters to which DY tuners do have. Still, I would like to know. I've had some lengthy discussions with some good 'authorized' tuners and they are very careful about what they say in that regard.

I've played with the SERT, then the TTS when Steve brought that out, then with PV and it's iterations, and some with SESTPro. The PV_TT is most appealing to me because of the access while riding, but the information regarding the parameters leaves me wanting.

I really appreciate the information the two of you just shared with those who've been following this thread since day one; and those who are invested in it now. Thanks much.

 

Thanks Jet- Yeh i guess I get a bit frustrated with some of the lacking data and current tuner mentality / unwillingness to share in regards to specifically, "HD Delphi". If you are a car enthusiast, and want to get info on tuning Delphi in general, you can find any bit of deep dark data you want- from experienced tuners. And the automotive tuning products are completely full featured without restriction. Most even include some very advanced suites of data logging software that assists with turning captured raw log data into improved tuning. really cool stuff.

So why then, the bad voodoo and hush hush mindset surrounding our stripped down version of a well known system? Seems pretty silly to me. It really hurts owners who have some knowledge of tuning and want to properly dial in their bikes to their own needs, add forced induction, etc. It also hinders new riders who want to learn more about tuning beyond "just use the auto tune feature" (which is perfectly fine for many, no discounting that!). Not like we are trading in nuclear secrets here. hah.

Anyway thank goodness for those here who do share advanced info and take time to answer advanced questions. We get a lot of mileage from Jamie / FM but that is only one guy, he's busy and we can't expect him to hang out and cover all questions in detail. We need like 5 of him. ;p

We need tuning products that continue to push the envelope and hopefully open up new parameters in the system for tuning. I don't know to what extent that is possible, but then again I don't know to what extent we are being restricted either.

 

I just got some very good and little known info on tuning spark timing using the wide band auto tune function of PV from another member here, Fat11Lo, wanted to post it up for anyone else here to read. Fat11Lo if I missed anything or stated anything incorrectly on the tuning steps please let me know -

This is applicable to wide band tuning only- AT Pro or TT. Not AT basic.

-----------
How to tune spark timing with PV and TT or AT PRO.

1. Tune VEs with TT or AT Pro Auto Tune first. You must get your VEs and AFR dialed in first before proceeding to tune spark timing. You cannot tune both fuel and spark timing in one step using this process.

2. When ready to tune spark timing, in WinPV timing tables or using the "quick tune" feature in the PV, bump timing map across board 5 degrees on your current VE-optimized tune. If you are doing this manually in WinPV, don't add timing to the idle, startup or decel areas of timing tables. Those should remain unchanged.

> Idle area is 20-40 kpa and 1250-750 rpm.

> Startup area is 95-100 kpa and 750 rpm. Actually you can exclude the entire 750-1000 rpm lines

> Decel area is the entire 20-25 kpa columns. You would go back later and manually tune decel timing separately to help cure things like decel cracking and pop.

>It's debatable whether you need to advance any timing in the cruise (light load) areas since it is already quite advanced. you could technically exclude the entire spark table values 50kpa and below at all rpms. but if you don't that's ok any knock will get trimmed since we will set 10.0 as the max knock retard value before running auto tune.

3. Prepare to do another auto tune session on your VE optimized tune. First be sure to set "Max VE learn" to 0 (so the AT does not try and adjust VE's), and make sure "max knock retard" is 10.0 for cushion.

4. Run the AT session trying to hit all areas of load and RPM, WOT etc. AT should trim any excess timing as needed to an optimum level for any given combination of rpm and load, and closer to best MBT.

You can run multiple AT sessions if neededand check the data logs. If you do not see any recorded knock events greater than 2-3 then you're good to go.
Any performance tuned HD will have some knock, and some of those detected knocks might be erroneous data caused by bigger cams, or temporary conditions like fuel quality, air temp, elevation, passenger on bike, etc. The spark knock removal system will do it's job if needed. If you keep trying to dial out any and all knock, you'll have a weak tune.

This can be repeated at any time. Now since I have not yet done this myself, the process steps are still "on paper" so to speak. Once I get my TT installed I will run through it and see how it does.
------------

About MBT and why it is important to tune spark timing, especially with cam or other performance related changes:

MBT timing = Maximum Brake Torque timing. Knock limit aside, at a given speed and flow rate it is the spark timing that gives maximum torque. It doesn't mean maximum spark advance. The word "maximum" refers to torque.

(simplified version to keep it short) If combustion starts too soon, gas pushes back on piston as it's coming up in compression stroke, creating negative force which reduces torque.
If the spark occurs too late, peak cylinder pressure is reduced and so is expansion force. So there is an optimum spark timing event for creating maximum torque. If we draw out a curve of torque vs spark timing advance starting out below MBT, as spark timing is advanced torque will increase until MBT timing is reached. After which point further advance will cause torque to drop back down. The top of the curve is somewhat flat, so the percentage increase in tq drops off as spark advance approaches MBT.

So typically we need to get a proper dyno tune to determine where these optimal spark timing events should occur to give us optimal MBT at any given point in the RPM/load range. No tuning products presently give us an obvious way to tune spark optimally to the engine in this manner. But with the outlined steps above we can get (hopefully) a bit closer to achieving this- Even though it was not the intention of DJ to have the PV's WB AT function used in this manner- It should still work.

I have also read "MBT" deciphered as "mean best timing", but since MBT depends on engine speed and load (and some other factors like fuel octane), that description doesn't seem to fit IMO... As usual, FWIW / YMMV and if I stated anything incorrectly please feel free to correct

 

Nice bike LA_Dog

 

thank you sir!

 

Ya know, that method was mentioned in the early Basic PV Help/Read me files,Cant really call it a manual but that's all we had then. Once you were satisfied with VE's,AFR,CDE,AE,DE, etc... It recommended setting VE learn to 0 and Max spark learn to 10, But...By doing so and enabling Basic AT it would still set AFR to 14.6 and disable most other settings as well as pulling 4* Spark Advance right off the top.Not an ideal representation of whats going on in the actual tune you were trying to fine tune timing on. So back then Log Tuner "was" the BEST tool to use for timing by using logged data from the actual tune you were riding around on. I did it carefully and with small areas at a time rather than adding X number of degrees across the board. And then pulled a little/added a little here and there to smooth things out. If your data showed say a 2 degree hit, Log Tuner would pull a much smaller amount of timing in the cell or cells just before and around the recorded event due to the lag time between the actual event and when the data was being recorded. That's a very simplified explaination of it. I ain't the smartest kid in the class but I could make it work.Then DJ "retired" it and stopped supporting LT. Even then one very smart member found a simple work around by editing the .cvs Log Files after DJ made changes in them in an update to the PV. Now with the Rushmore's I have no idea, I recall a few posts by Jamie (FM) telling us how the Spark Knock detection data logged by the Can-Bus, ECM, PV differed from the way it used to be on pre Rushmore models. So if they have updated the PV software to work like the old Log Tuner in TT and/or Pro WB AT that would be a good tool to have. I don't know which or if any tune paramaters are disabled or changed in WB Pro AT besides AFR going to 13.0 for tuning. TT seems to be mainly focused on realtime VE/AFRs. I wonder if AT'ing with TT set to VE Learn 0, Sprk Learn 10 would really be more like the old LT after all.