Ka24et timing map

Discussion about ECU Tuning Products and Theories

Ka24et timing map

Postby Crack240 » Fri Feb 10, 2017 4:18 pm

Whats up fellas. I've had my car tuned multiple times and I've been going through all my tunes trying to get a grasp on what they did for timing, as I want to tune my next motor by myself. Here are a few screen shots of different tunes on the same setup with different boost levels.
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby Crack240 » Fri Feb 10, 2017 4:29 pm

Built soch ka 7.9:1 CR 18psi pump gas gt3076r

Image
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby Crack240 » Fri Feb 10, 2017 4:31 pm

Built sohc ka 7.9:1 CR 21psi on 93 pump gas gt3076r

Image
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby Crack240 » Fri Feb 10, 2017 4:38 pm

Now this timing map is the same ad the map on my built motor@21psi but the tuner used it on my buddies stock motor @13psi. Image
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby Crack240 » Fri Feb 10, 2017 4:58 pm

I see most of the ka-t guys run around 12-14 degrees @ around 18-16 psi. I feel like my maps are way off from where they should be. Maybe the tuner was just going until he saw max tq and left it..idk but both motors stock and built spun bearing within 6months of these tunes. (Not sure if tunes were the issue , that's why I'm here lol)
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby BigLoukaT » Sat Feb 11, 2017 7:01 am

First, comparing DOHC to SOHC timing maps isn't necessarily apples to apples - SOHC combustion chambers by design will require more ignition advance than DOHCs to achieve the same flame propagation completion relative to crank movement.

Second, the way your tuner has established your load axis, means that for ANY of the boost pressures you mentioned as being run, only the very top row is being accessed at 18 psi or 21 psi. 204 kpa is equivalent to (204kpa-101.3kpa)*14.7PSI/101.3 kpa = 14.9 PSI boost at sea level.
13 psi boost = 190.9 kpa (ok, so this one mainly uses the 185 kpa load row)
18 psi boost = 225.34 kpa
21 psi boost = 246.01 kpa
There is basically no change in commanded timing from 120kpa to 160 kpa. This means that at best case, your tuner is not using the load axis efficiently (two or three of your 12 load axis rows are not doing anything differently - your map could be run off of 10 rows basically).
At worst case (and what is happening here), is that there is no differentiation in ignition timing once you surpass 204 kpa or 14.9 psi of boost. The ignition timing you command at 15 psi, will be the same ignition advance for 18, 21, 30 etc.

In the attached screenshot, and concentrating on peak torque (4300 or so), the tuner has removed 9.5 degrees of timing for 12 PSI (185 kpa) and 10 degrees of timing for 15 psi (204kpa). UNFORTUNATELY, as you increase boost, no further timing is reduced.
As you increase boost from 15 psi in this map, your ignition timing gets increasingly more aggressive related to boost pressure.

IMG_20170210_183320_zpsof1bmyhp_biglou.jpg


I can't say whether or not this ignition map is the cause of spun bearings. However, I'm glad to read you are seeking to do your ignition map yourself, because IMO the tuners have not spent your money very well so far. I will admit, I do think your 2nd/3rd guy did a bit better and incorporated some finer details (increase after peak torque to chase the piston), but that's about all I like about that map.

Post up your msq if you'd like me to look at the rest of the tune and give you a second opinion.

I posted my ignition table to show you what I mean about load axis distribution. I run 8 psi which is 156 kpa. I have reduced more than 1 degree per psi of boost, and have not incorporated any additional advance after peak torque. I have been running a similar map for the last 3 years at least, and my engine has been beat relentlessly. Still on a stock block, 200k+ mile engine that was pulled from a backyard with no cover. I intend to build some knock muffs and make this a bit more efficient this summer, but it's hard to mess with something that has worked so far.
biglou_ign.JPG


As you're running more boost, you would use more than two rows in your boost region, but I would be very surprised if you needed more than four total to get enough resolution in the boost region.

eta: just seeing my ignition map for the first time in a year or so, I've realized that I have some goofy **** going on in the 80-100kpa and 2000-3700 region. My map is far from perfect, but it was free
1990 S13
Boosted single slammer
MS DIYPNP

npx from 240sxforums wrote:i figure from my very limited knowledge about the 240 and under the hood about cars in general i would follow the sr20det trend.
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Re: Ka24et timing map

Postby Crack240 » Sat Feb 11, 2017 8:56 am

Here is the tune that is on my car at the moment for 21 psi. I usually run 13-15 psi on track days
Attachments
CurrentTune.msq
(108.58 KiB) Downloaded 24 times
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby BigLoukaT » Sat Feb 11, 2017 5:15 pm

Is your idle pretty lopey? 10% fuel difference between load/rpm cells at idle is a pretty stark difference, and any change in rpm/load may send your engine into a vastly different fuel region.

Same comment about your ignition table applies to your fuel map - load axis ends at 204kpa. I would prefer to see your load axis hit the highest boost you plan to hit (or more). The four load rows from 110kpa to 160kpa are not doing you too much good IMO - you likely don't spend very much time in those cells and the interpolation will take care of the momentary fueling needs. At 21 PSI, I would want to see a table that reaches at least 250kpa to cover the bare minimum.

Do you have a cam in this engine? Your peak VE values seem to be focused later than peak torque on a stock cam motor - could be a lot of additional fuel that you're not using after peak torque.

Additionally, seems like you're commanding a lot of fuel on your 204 kpa line (and in your higher boost ranges in general). VE at 100kpa (4600 rpm) of 85 to 142 at 204 kpa (with Multiply MAP = on) implies that you are commanding 67% more fuel per amount of air up there. With multiply map on, roughly the amount of extra air is already taken into account in the fuel equation (so let's assume that's equal and relative). I would estimate that your fuel is very rich in higher boost regions - if that VE of 85 at 100kpa nets you 14.0 AFR (assuming lean just to make sense of the resulting number), the extra 67% of fuel (not counting the increase based on MAP pressure alone) would drive an AFR that is 67% richer than 100kpa. 14.0/1.67 = 8.5AFR. I doubt that you are that rich, but if it's anywhere close to that, it's possible that you've been diluting your oil with fuel from running so rich, and that could easily lead to spin some bearings.

Your fuel pressure regulator does have a reference to boost/vac, right? That would be the only thing that would make sense to me if your FPR wasn't adjusting for boost, and that's why you need to command such high fuel values in boost.

Do you have a run log/msl that ties to this tune?
1990 S13
Boosted single slammer
MS DIYPNP

npx from 240sxforums wrote:i figure from my very limited knowledge about the 240 and under the hood about cars in general i would follow the sr20det trend.
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Dont Question My Nissan Knowledge
 
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Re: Ka24et timing map

Postby Crack240 » Sat Feb 11, 2017 5:36 pm

The idle wasnt super lopey I figured it was the cam making it feel that way.yes I do have a cam in the engine and the fpr is rising rate and does see vac/boost.on higher boost levels the AFR was usually pretty good ,a little on the rich side (10.8-11.4)

And my oil constantly smells like fuel I tend to change it out when it gets bad. I did try to run the VE analyze feature and it made the car feel a lot smoother but I wasn't too sure about it so I put the original tune back on.
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby Crack240 » Sat Feb 11, 2017 5:37 pm

I'm going through my PC now to try and find a mega log file associated with that tune
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby Crack240 » Fri Feb 17, 2017 5:13 am

So I can't find a log of my car on 21 psi. I have one @12-13 psi but I can't figure out how to upload the MSL.
89 Ka24e-t
completely stock
49k miles
550cc injectors
z32maf
GSP.50 trim
38mm WG
10 psi
260wtq
Crack240
Driving Mom's Station Wagon
 
Posts: 49
Joined: Sun Dec 06, 2009 6:56 pm
Location: Norwalk, CT

Re: Ka24et timing map

Postby BigLoukaT » Sat Feb 18, 2017 7:07 am

I'll send you a pm with my email, feel free to send it
1990 S13
Boosted single slammer
MS DIYPNP

npx from 240sxforums wrote:i figure from my very limited knowledge about the 240 and under the hood about cars in general i would follow the sr20det trend.
User avatar
BigLoukaT
Dont Question My Nissan Knowledge
 
Posts: 879
Joined: Sun Jul 23, 2006 11:03 am
Location: MA

Re: Ka24et timing map

Postby BigLoukaT » Sat Mar 04, 2017 12:52 pm

no MAT (intake air temp) reading - stays at 70 full time. This needs to be fixed or your fueling during different temperatures will not be correct.
Battery voltage very low through log - 11.3-11.8 at it's highest. Does the readout from tunerstudio match what you measure at the battery?
Rich - mid 10's in boost
Injector Duty cycle impossibly high. 1076 seconds in the log - over 100% duty cycle. All the way up to 158.2% duty cycle. Though as you know, log doesn't match your tune file (VE1 recorded as 220 at 5962rpm and 188.7 kpa, while tune file has ~140 VE1 from the table), so I can't immediately tell if that has been rectified by your log file. I would estimate you're still at or above 100% duty cycle there though based on the tune you posted above (140/220 * 158% = 101%)

How soon are you retuning? First step in my book is to concentrate on rescaling the fuel and ignition tables to cover your intended range, thereby allowing the ecu to command different ignition timing at 15 psi and 22 psi.

I uploaded your msl here for anyone else that might want a look - if you don't want it posted, let me know and I'll delete

edit: actually, just realized the date stamp on that file - is this a recent log? Can you grab a copy of the tune you were running that day?
Attachments
2017-02-16_18-31-53.zip
(169.76 KiB) Downloaded 5 times
1990 S13
Boosted single slammer
MS DIYPNP

npx from 240sxforums wrote:i figure from my very limited knowledge about the 240 and under the hood about cars in general i would follow the sr20det trend.
User avatar
BigLoukaT
Dont Question My Nissan Knowledge
 
Posts: 879
Joined: Sun Jul 23, 2006 11:03 am
Location: MA


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