Tips on fine Tuning the DTT TCFI IId

[-SeabrookTrickBagger]

Doug,

Chime in when you please.  We can always benefit from your varied and deep experience.   I am just an afficianado whom has made nearly every mistake you can make and I am not an expert.

There was another fellow on this site whom really knew the DTT TCFI III on down to the II.  He bailed out at some point; too bad 'cause he really knew it and answered a lot of questions I had in addition to those answered by Doug over the years.

If anyone knows much about the 2d tables, chime in 'cause they are mystery to me, for the most part.  I know a few things about them, such as the Start Adder Table interaction with the IAC, the Cranking Fuel Table and the Priming Fuel Table.   Same goes for Asynchronis Gain adjustment and a few others that are somewhat mysterious.

[-SeabrookTrickBagger]

Overdriving, underdriving, driving ........ injectors.

In parameters, you insert the crankshaft horsepower, not rear wheel horsepower.  And, you insert your injector flow rate in grams per second.  (I asked Chris S. if the injector flow rate was measured at 3 bar or HD fuel pressure.  He said it did not matter.  For example, a 6.1gps injector flowed at HD fuel pressure is equivilant to 5.3gps flowed at 3 bar ----- if I can multiply correctly.  I think it matters).  In any event, if you tell the program that the engine is making 130HP at the specified RPM in parameters AND tell the program that the injectors are 5.0gps, then it seems "logical" to me that the injectors will work really hard to achieve 130HP.  If in fact your injectors are 5.3gps injectors, then I assume the injector timing pulses and duration pulses of the injectors will be as if the injectors are 5.0gps which (it seems to me) over-drive the 5.3gps injectors (since if you put in parameters that the injectors are 5.3gps, then the timing and duration injector pulses would be lower).  Whether any of this matters, I don't know.  I am not interested in the semantics, just the operation.  It was just an experiment I ran at one time to see what would happen.  I thought the engine ran a bit better "cheating" the program.  But, it might have just been a rich condition which would tend to smooth the engine a bit.  I don't know since I did not check the BLM activity.  Whatever the difference was, it was not a great difference and I don't cheat the program as a rule.

[-SeabrookTrickBagger]

Correlating posts 1 and 18 ....... Alpha N with AFR


So, you have read and deciphered as well as implement posts 1 AND 18 and you are now ready to run down the road, but it ain't over yet.  Now, to complete that process one needs to consider this:  if you change the alpha n numbers in deceleration cells AND the BLM is active and trying to compensate it is because your AFR number in that cell is not what you want it to be.  Here is how it works:   if you put an alpha n number in a deceleration cell, and if the AFR command number in that cell is not in "harmony" with that Alpha N number, the BLM will try to adjust the Alpha N number to match the AFR Command; that is what I mean by "harmony."  So, what to do? 

Instead of changing the Alpha N numbers in deceleration cells, you can just put the desired AFR command in the deceleration cells of the afr table, such as 14.0.   The BLM will try to adjust the Alpha N to reach 14.0 AFR unless you exceed the adjustment range (79 to 125 more or less) of the BLM.  However, for those deceleration cells not accessed by the BLM, you need to do the manual smoothing mentioned in post 18. 

I wrote posts 1 and 18 to emphasize smoothing, the four theoretical table concept in regard the Alpha N table and the general concept of having to determine which are performance/acceleration and which are deceleration cells since those determinations should precede just trying to stick AFR command numbers in what you suspect are performance or deceleration cells without giving any thought to it.  In other words, my process is a more "performance oriented" methodology INCLUDING fuel mileage considerations.  If you figure out which are unused cells, performance cells, deceleration cells and idle cells, plugging in AFR command numbers becomes an easy exercise and will prevent, to a large degree, causing one big mess of your AFR table.  After you do all this, run your bike, BLM it and after you are satisfied with the BLM, go to the Alpha N table and manually smooth the four theoretical alpha n tables.  Ride it again.  If it is rough in a few spots, go back in those few spots to the prior number or go the other direction with a number in that cell since it could be exhaust reversion or exhaust over-scavenging or intake fuel robbing or just an inexplicable anomoly peculiar to your set-up or build.  More importantly, this process will help you understand what is going on and probably lead to Nirvana ................ or Utopia or a DTT honeymoon. 

Hopefully this post brings together the AFR and Alpha N tuning process for those whom are interested.  The way I described to do it is not the only way to do it.  It is the way I do it and nothing more.  For those wanting to take the short cut, well, take it to someone like Doug.  And if he is too far away, then plug in AFR numbers that look fairly good and let the BLM do the rest; it will be ride-able in all probability.  Good luck.

[Airglider]

STB,

What happened? You were going so well teaching us the little tricks you have learned. Logging in was like setting up the works, the tourniquet, the pin prick, then the flood of knowledge would invade our brains. It's been a week since you posted. I'M JONESING!!!

More, Please send More!

Thanks,

AG

[-SeabrookTrickBagger]

STB,

What happened? You were going so well teaching us the little tricks you have learned. Logging in was like setting up the works, the tourniquet, the pin prick, then the flood of knowledge would invade our brains. It's been a week since you posted. I'M JONESING!!!

More, Please send More!

Thanks,

AG

Don't know much more!   This is a fine tuning thread and not a basic tuning or "fix it" thread.  Basic tuning would take a few more posts, but it is more than my tired fingers can handle 'cause you have to start with "put a good floor fan blowin' on the motor" and go from there.  I guess I wanted to write all this for me and others to have a basic reference guide or a suppository for the CRAFT moments -- I mean "repository".

[Airglider]

Just sent my heads out to Bean this morning. I am going with a Woods 6G at 10:1 in my 95 with flattops.

Would I be better off starting with the generic base map or altering the one I generated with the Andrews 26G at 9.5:1?

TIA

AG

[-SeabrookTrickBagger]

Just sent my heads out to Bean this morning. I am going with a Woods 6G at 10:1 in my 95 with flattops.

Would I be better off starting with the generic base map or altering the one I generated with the Andrews 26G at 9.5:1?

TIA

AG

Compare the two alpha n number charts and "get a feel" for which one looks better.   This assumes you have tuned the map you choose to a degree that the BLM activity is minimal.  I suspect the tuned map with the Andrews would work better as a base map than the generic map assuming the Andrews map was developed from the base map.  The DTT TCFI has an effective tuning range of 20%, beyond that the unit will not tune very well by itself without a lot of hands-on manipulation.  I suspect that the most significant change in the map you will see is that the fuel needs move up the RPM scale since the 26 is a thumper cam.  Ask Bean if he suspects you will see a HP increase over your current build of more than 20%, if so, you have a bit more work to do than just BLMing it two or three times.  If you really want to get it right and tight, my last post integrates the main points of fine tuning and hopefully that will help you.

Personally, I find it fun to mickey with the TCFI, but a lot of people don't find it fun.  While I prefer to ride than wash or tune my bike, it is fun for me to go for a long hard putt and at the end of the putt, look at the logged data and make changes.  However, you can degenerate the map when you start making manual changes and that was the reason for my last tuning post.

One final matter involving the alpha n table.  On the IId, I find that the 1500 rpm cell at 2.5% throttle position just will not tune in that the longer you tune that cell by BLMing it, the worse it gets.  I notice a hesitation in the engine just off idle.  So, I find the best alpha n number for that cell and then put a "1" in the BLM cell at that rpm and throttle position:  it will no longer tune but will log data.  I don't know why this is ........... but enough people have experienced it that I believe it is a programming glitch and not due to build configurations of the engine/exhaust.  In addition to feel of the engine, you will notice this (if it is a problem) by looking at the alpha N number in that cell --- (2.5% tps at 1500 rpm)  if it is lower than the number above it (0 throttle position row at 1500 rpms) and assuming the number above it is a good number ( 0 tps at 1500), then you too have "the problem."  You can put a 2 point higher number (than that found in the cell above it - 0% at 1500) in the 2.5% row at 1500 rpms and see if it smooths out.  If so, then go up two more points, run it and then look at your logged data and check out the afr.  If the afr is good, stick with the good number and put a 1 in that cell in the BLM after you find the right alpha n number.  For example:  22 in 0% tps at 1500, but the 2.5% tps at 1500 shows 18. So, put in 24 in 2.5% at 1500 and then 26, until you get a smooth transition off of idle.  Then put a "1" in that cell in the BLM tables -- since there are two BLM tables even though I speak as if there is only one.

The advantage of the TCFI is that you get tuning information at all rpm levels and all throttle position levels as opposed to just tuning information at wide open throttle on a dyno if that is how the dyno tuner chooses to tune it.  A good tuner using a dyno can simulate different loads, rpm, speeds (gear chosen) and tune the heck out of it.  And that would take a lot of work.  You can do a lot of the same things (although you won't be able to measure HP or torque calculations) with the TCFI.  The point of this is to show you how much tuning you or the BLM has to do which takes time:  you have to hit all load conditions and all rpms to tune the whole map.  I find that putting the Palm pilot on the bike and doing spot checks is a valuable tool for small problematic areas.  For example, it diagnosed the high afr spikes I was seeing in logged data which the Palm Pilot told me was due to deceleration events and not something else.

Good luck.

[Don D]

After I get uncovered here I am going to get my 07 dialed in
I have had the WEGO IId for a few years and one and the only remaining problem is when I stop for gas, warm motor, and restart the idle hangs at 1500 until I ride off and come to a full stop and allow it to normalize. This can be very annoying. I have had some complex schemes to work all the warm-up tables but I would really like to nip this easily and move on or I will go back to the Delphi.
Any help appreciated. TIA

[Airglider]

STB,

Thanks again for sharing your knowledge. Are you using the 14.0 afr across the board in the 0 row from 2000 or so up? I am happy with my map except for the 35 mpg. I have locked the values in that range in the Alpha N. Maybe this is where my mpg problem lies. I am undergoing upgrades currently and will take your suggestion and start with my current map.

Would you share your map and build specs for educational purposes?

Like you, I enjoy tinkering with the mappings. After making changes and riding to work and home (approx 50 miles), I take the laptop out to the garage and download the new data. Gives me something to think about as I drift off to sleep.

Thanks again,

AG

[-SeabrookTrickBagger]

STB,

Thanks again for sharing your knowledge. Are you using the 14.0 afr across the board in the 0 row from 2000 or so up? I am happy with my map except for the 35 mpg. I have locked the values in that range in the Alpha N. Maybe this is where my mpg problem lies. I am undergoing upgrades currently and will take your suggestion and start with my current map.

Would you share your map and build specs for educational purposes?

Like you, I enjoy tinkering with the mappings. After making changes and riding to work and home (approx 50 miles), I take the laptop out to the garage and download the new data. Gives me something to think about as I drift off to sleep.

Thanks again,

AG

I don't remember what my afr commands are in the deceleration cells since I deactivate the afr commands in BLM by inserting a "1" and used alpha n numbers to get it where I wanted it which was by sound and feel.  I recognize that an alpha n number at, for example, 3000 rpms in the 0% row are deceleration cells.  So, I put a number about 5 points lower than the idle alpha n number and go for a putt listening for deceleration popping and a feeling like it is not slowing down quickly enough (too rich, maybe).  I don't know what the AFR number might be but when I look at the log, I might initially see a spike to 17 AFR which does not worry me since I don't have to worry about detonation when decelerating and the afr command is not controlling the alpha n number since I deactive BLM as stated above, in those cells.  I also watch for heat build up.  After doing all that, I end up with a alpha n number which works on my bike and my not work on yours due to exhaust reversion or over scavenging issues.  Again, if I were riding in the mountains with long down hills using engine breaking, I would run the deceleration cells richer.

I can provide my map to you, but trust me, it will do you no good since my heads, compression, cams, advance timing, exhaust, intake etc. are so different than most other builds, not to mention my altitude (3 feet below sea level, effective).  Let me give you one example:  I can run a 29 alpha n in the idle cells.  I bet your idle cell alpha n numbers are not very close to that number.  At present, I am running 26 in the idle cells and I intend to reduce those numbers to see how low I can go and get a good hot soak start when it is 100 degress F this summer.  I bet I cannot go much below 24............. .  Again, I bet your alpha n idle cell numbers might be around 19 . ........... just guessing.  What are they?

[Airglider]

STB,

My "0" cells are:

RPM     500,   750,   1000,   1250,   1500,   1750,   2000,   2250 and up

Alpha N  34,    32,    21.5,    18.0,    15.5,   16.0,    15.0,    13.5 and up

I am running "1" in cells 1750 and up. I had gotten the decel popping under control with these values. I expect I will be massaging the values when my build comes back together. These values are with the 26G at 95".

Any thoughts?

AG

[-SeabrookTrickBagger]

STB,

My "0" cells are:

RPM     500,   750,   1000,   1250,   1500,   1750,   2000,   2250 and up

Alpha N  34,    32,    21.5,    18.0,    15.5,   16.0,    15.0,    13.5 and up

I am running "1" in cells 1750 and up. I had gotten the decel popping under control with these values. I expect I will be massaging the values when my build comes back together. These values are with the 26G at 95".

Any thoughts?

AG

First, I wonder why your 1500 value is lower than your 1750 value.  It does not mean anything is wrong, it just means I would look at the reason for that.  My idea is that the 1750 alpha n number should be lower than the 1500 rpm number, but it is hard to tell over the internet.  Look at my post about downward progression in ROWS as rpms increase (and upward progression in COLUMNS as throttle position increases) which are general rules and not written in stone.  What do you see?

Secondly, if your bike does not idle above 1500, then why not put a "1" in the 1500 cell if you have found a good alpha n number to put in there?  Might do that later after you get a good alpha n number in that cell........ .

Now you see why my map won't do you much good since I run 29 or 26 in my idle cells.  Your average number is 20 since you have different numbers in each idle cell:  I assume your bike idles while bouncing below 1000 and above 1000 observed in real time data in the Log program.  Let me know if it idles above 1000 AND below 1000 under any normal condition even if only briefly AFTER the first five seconds or so AFTER the engine is started.  I assume your bike does not idle above 1250 rpms when in stable idle condition as opposed to immediately after a start-up.  What rpm is your idle set at in the 2d table at various temps?

1.  Check out reply #10 and tell me what you think about your alpha n numbers at 1000 and 1250. The "answer" is in reply 10 if your bike idles above and below 1000 rpms in a stable idle condition.   In reply 10, I mention AFR numbers, but keep in mind that you can tune using the alpha n numbers which ultimately, are the same thing, front cylinder trimming excepted. 
2.  Your 500 and 750 cells are no problem since that is above idle rpm for a twin cam.  You can whittle those down and see if it affects starting.  If it does not, whittle them down to 22 each.  It is merely a manual smoothing exercise in, largely but not entirely, unused cells.  You want to test this on a hot soak starting.   After you look at reply #10, we will look at 1500 and above.
3.  We need to look at more than the 0% row for idle control:  all the way up to 7.5% throttle position at idle rpms.  We can do that after we finish the 0% row.

[-SeabrookTrickBagger]

AG,

Please consider moving your questions to a separate thread you create in the AFR Zone since I think that I would like to keep this thread as a reference thread and not a "fix it" thread.  Moreover, others (who are "real" mechanics and tuners) might join in, too.

[speedglide]

Seabrook, Doug, or anyone with info....
How would you suggest balancing out head temps at cruise?  I'm in the fine tuning process, but can't get the cylinders balanced out temp wise.. Of course, it's still pretty cold here in MI, and I think to be fair, I should wait until the temps are above 45 to really get a good reliable head temp at cruise.  My front temp may come up a bit. My inital thought is I may need to fine tune the cylinders by going open loop and manually adjusting the front trim tables..
Jason

[tarheelrdr]

I too would like some information on how to get the frt/rear cyl. head temps closer together, I have an '04 ultra with a 113" Headquarter's build-10.5/1 comp. D&D fatcat/performance baffle, 51 HPI t/b w/marren 5.04 gps injectors. My rear cyl. is a consistant 75-80 degrees hotter. yesterday outside temps @ 75, my frt was 280 and rear-355. my rear cyl. off-set is a "0". Any advice is greatly appreciated.

Thanks

Tim

[Sonny S.]

I too would like some information on how to get the frt/rear cyl. head temps closer together, I have an '04 ultra with a 113" Headquarter's build-10.5/1 comp. D&D fatcat/performance baffle, 51 HPI t/b w/marren 5.04 gps injectors. My rear cyl. is a consistant 75-80 degrees hotter. yesterday outside temps @ 75, my frt was 280 and rear-355. my rear cyl. off-set is a "0". Any advice is greatly appreciated.

Thanks

Tim

bump

[speedglide]

Tarheelrdr-
What speed are you riding to get those temps? And exactly were are you measuring? Man, they vary 50 degrees or so depending on where you put that laser pointer...
Just for consistency, I have been taking my temps on the machined surface between my spark plug and compression releases.
I'm usually 40 degrees different at hwy speeds, 75-80mph.  At speeds under 50, my heads are usually within 10-20 degrees of each other.  I'm still in the early tuning stages. 

[Sonny S.]

Anyone measuring temps here in the yellow circle ?

[tarheelrdr]

Tarheelrdr-
What speed are you riding to get those temps? And exactly were are you measuring? Man, they vary 50 degrees or so depending on where you put that laser pointer...
Just for consistency, I have been taking my temps on the machined surface between my spark plug and compression releases.
I'm usually 40 degrees different at hwy speeds, 75-80mph.  At speeds under 50, my heads are usually within 10-20 degrees of each other.  I'm still in the early tuning stages. 

averaging 60 mph on rural country roads and I take  the reading just below the base of the sparkpllug, I put the laser on the sparkplug base and the instructions said the reading is about a 1/2 inch below.

I tried  -3 degrees rear cyl. offset yesterday on a 100 mile ride and the temps were still about 75* hotter on rear. 285 frt/350 rear.
Any suggestions are appreciated.
I took off the lowers a couple of days ago and the temps did come down 20*. But I prefer to have them on.

Thanks

Tim

[speedglide]

I did have the vinyl engine guard lowers on, and when I took them off, my rear cylinder dropped 40-50 degrees! So I guss I won't be running them unless it's below 45 degrees on mine.  I'm not sure what to tell you on the temps, mine are pretty close at 60mph, maybe 20 degrees different, and they are around 280 front, 300 maybe 310 rear...
What is your timing at 2500, 2750, 3000? What is your AFR set at in the same rpms, at say 10% throttle?
Jason

[speedglide]

Anyone measuring temps here in the yellow circle ?

No, looks like the yellow circles are targeting just above the exhaust valves?

[tarheelrdr]

I did have the vinyl engine guard lowers on, and when I took them off, my rear cylinder dropped 40-50 degrees! So I guss I won't be running them unless it's below 45 degrees on mine.  I'm not sure what to tell you on the temps, mine are pretty close at 60mph, maybe 20 degrees different, and they are around 280 front, 300 maybe 310 rear...
What is your timing at 2500, 2750, 3000? What is your AFR set at in the same rpms, at say 10% throttle?
Jason

At 16 map---2500-33.6/2750-35.4/3000-37.0
at  18 MAP---2500-25.7/2750-27.6/3000-34.8
AFR IS   14.1 at 2500-3000
Are you running any rear cyl. offset at all or still at -0-?
since it's getting hotter I might try pulling the lowers off again. outside temps are in the upper 80's now in NC.
WHAT are some other reasons why there would be so much timing difference between cyl.s'. This was my first attempt at doing a cam/topend build. so I might have done something wrong in the beginning.

[speedglide]

My timing was actually a few degrees higher than yours, but I have not ridden in 80 degree temps yet. My AFRs were set at 14.2.  I'm currently working new tables to lower my timing down to the mid 30's and 14 flat AFRs.  I think my current settings will be too high for 80+ degree days. I currently have my rear offset at 0 degrees. My plan, once I get the rear cylinder close to the optimal operating temp,( which is supposed to be 300 deg, yet Kevin did state on their forum that his rear cylinder will creep up to 330-340 on long hwy runs!!!) is to turn off the auto tune and start manually adjusting the fuel map for the front cylinder to bring it up to proper temp, then watch the spark plugs.  Kevin stated that if the cylinder temps were close, the plugs looked similar, and you are getting 40+mpg, you are good to go.

[tarheelrdr]

My timing was actually a few degrees higher than yours, but I have not ridden in 80 degree temps yet. My AFRs were set at 14.2.  I'm currently working new tables to lower my timing down to the mid 30's and 14 flat AFRs.  I think my current settings will be too high for 80+ degree days. I currently have my rear offset at 0 degrees. My plan, once I get the rear cylinder close to the optimal operating temp,( which is supposed to be 300 deg, yet Kevin did state on their forum that his rear cylinder will creep up to 330-340 on long hwy runs!!!) is to turn off the auto tune and start manually adjusting the fuel map for the front cylinder to bring it up to proper temp, then watch the spark plugs.  Kevin stated that if the cylinder temps were close, the plugs looked similar, and you are getting 40+mpg, you are good to go.
[/quote

Thanks for the quick reply, just what would happen if I can't get the temps any closer. What would happen to the engine in the long haul. It's been like this for about 2 years now, I just bought an i/r temp guage and holy s**t doug @ HQ tells me that some magor damage might happen. What will happen?

thanks

Tim

[speedglide]

I wouldn't be as worried about the temp cylinder seperation as much as I would high temps.  As with any overheated motor, piston and cylinder wall damage would result.  And I would not worry too much about your currrent temps, 350 isn't extreme. As I stated earlier, Kevin stated his rear cylinder would creep up to 330-340 on extended hwy runs. I bet you drop a good 30 by removing your lowers. You may notice a bigger impact from minor changes in timing and AFRs with the lowers off.   If you can get down to low 300's on the rear with timing changes, I would turn your auto tune off and start manually adjusting your front fuel cells to bring the front cylinder up!