Update on my car and review of the Enthalpy Ecu

[Jookmasta]

So i know its been a while since i posted about my car but as many of you know, if everything is running well with it since the last changes or add ons, then there's not much to post up on it. So down to the update. Well i finally got a break from school and i was able to get to my car finally. My friend 240sxsickness deserves super thanks for all the help with the car while i was out of the country. The upgrades consisted of 480cc deathwerks injectors, a SARD fpr, and an Enthalpy ecu. The injectors came with the printouts and all that jazz and have been running fine. The Sard fpr is a nice little unit that ran about 100 bux (not including the fittings) and sits currently on the firewall near the intake mani. The fpr has been working fine and no issues so far with it.

Last but not least, the golden Enthalpy Ecu. First off, i will say that its worth every penny. By far, anyone not running a tuned ecu, standalone, or emanage ultimate should invest in this cuz for the price, it really eliminates alot of guessing with certain variables and will most likely make ur car run better than u could even imagine. So as a fellow ka-t that was on a budget, i was previously using an SAFC, and the base retard timing method to tune my car. not to say that it doesnt work, but the power you make (both in and out of boost) is probably not as safe or as much as with the enthalpy or other variants i listed in the beginning of this paragraph.

So of course, i started out with just the stock wastegate boost setting (6-7 psi) and ran the car like that for about a week. There was a significant increase in gas mileage due to the ecu as i can now achieve more than 300 miles out of a tank of gas.............. Me and my friend did monitor the a/f's via the Zeitronix while in boost and the a/f's were a SOLID 11.8-12.0 across the board. It was crazy as i think on one of the runs the a/f stayed at 11.9 while flooring it and never changed.

Now after running like that for about a week and a half, i decided to up the boost and see what she could do. So we went out to the "truck road" and did a little tuning session by doing boost pulls, monitoring them via the zeitronix, and by checking the sparkplugs after each pull to check for detonation and to look at the color of the plugs to ensure an even burn. So first adjustment was to about 10 psi. This went well but we thought that the timing should be retarded like 1 degree as ten psi wasnt going to be the final mark for the nite. Another adjustment on the mbc netted a real nice 15 psi pull which once again, the a/f's were a SOLID 11.4-11.5. Then of course we were like, y not more? lol. So the final adjustment led me to a solid 1.30 bar worth of boost. of course my luck, the labtop battery called it quits so it was a blind run without the aid of the zeitronix but we did check the plugs immediately after the run. The car didnt break up through out the entire pull at all and the plugs checked out fine but since we didnt have any data on the a/f's, i decided to turn down the boost as i really didnt know how the a/f's were looking and since at 19 psi, the car feels like its hydroplaning lol. So as of now the car is set at around 15-16 psi (pending on weather conditions) and is pulling strong like no other.

I will comment some more on the ecu as there are some things that i found to be nice. Of course, Enthalpy will tune for your z32 maf so no need to make that adjustment on the SAFC anymore. Next thing is the rev limiter and speed governor. The speed governor is eliminated and the rev limiter is defined at where u want it. I put mine to 7200 or 7300 since im all stock internals and what not. Last but not least is the atmospheric BOV. I run a greddy type S and with the Enthalpy, i can now go to neutral without fear of gigantic backfire after moving off again and without fear of the car stalling.

Unfortunately, I wasnt able to check the total timing i was getting due to the lack of a mdm or snap on control module. If i get the numbers on the timing i will let you know, but im sure it's the same as cory's (nissanfanatic).

All in all, that ecu is amazing. I wish it was out back when i went ka-t. Definitely worth every bit of money. As for my car, i think i am really happy where it is right now. 16 pounds out of the str8 t3 is enough to put the car fully sideways in 1st and second gear and i know for sure that the car is running 13's on the track. My main goal was to just run solid 13's with the car while still maintaining its reliability. So now that i have accomplished that goal, i will enjoy it for what it is.

[NateDogg]

Just goes to show the Enthalpy ECU can do wonders but can't stop people from running 20psi on 480cc without any datalogging!!!

ARE YOU NUTS!!???

What octane are you using/tuned for?

[GEO]

price and turn around?

[Jookmasta]

well didnt mean to run 19 psi cuz as you very well know, u can't predict what the boost level is when your adjusting an mbc. nonetheless, i turned down the boost and its all good.

and for geo, price was 500 bux and the turn around time was 4 business days from when he gets the ecu. just be VERY VERY VERY VERY detailed when ur describing ur setup to get tuned for as i'm sure you want to get all that can be taken care of by the ecu done to ur ecu.

[MarkEmark]

Makes me wish all the more that Enthalpy existed when I bought my JWT ECU...Too bad he doesn't program them for Ford Cobra MAFS, otherwise I'd have sold my JWT by now and bought his....although I guess I could always sell my Cobra MAFS (costs quite a bit more than a 300zx MAFS) and JWT ECU to someone on ebay and buy his ECU...I may very well do this if I'm not pleased with the power I make @ 15 psi. We'll see.

What's funny is that I was just reading a post on Fresh Alloy where some embittered doucherag was saying tuned ECU's are a complete joke and that fully stand-alone is the only way to go.

Anyway, have you dynoed the car at all?

Is the engine built or stock block?

[Edub1]

Increasing boost shouldn't change A/F ratio because the MAF should keep adding fuel. This isn't a fixed number.

How much boost did he tune for? The timing is fixed, so either he was very conservative with timing or you have been very lucky.

I'd lower your boost back to what he tuned for before you blow your motor. Either that or add a BTM.

[MarkEmark]

Increasing boost shouldn't change A/F ratio because the MAF should keep adding fuel. This isn't a fixed number.

How much boost did he tune for? The timing is fixed, so either he was very conservative with timing or you have been very lucky.

I'd lower your boost back to what he tuned for before you blow your motor. Either that or add a BTM.

Not worth it to blow the engine up just for a short adrenaline rush...

The more I think about it, the more absurd JWT's "tuned" ECUs seem to me...they don't take into account turbo size, any head work (cams, valve job, larger valves, different valve springs, etc, which can allow you to run more advanced timing), boost level, anything like methanol injection, or even octane used (I think they by default tune them for 91 octane because there's a lot of cheapos who don't feel like paying for 91 or just don't have 93 in the area). Kind of sucks, because at 15 psi with my turbo and modifications, I could probably make 330 rwhp on an Enthalpy ECU; with a JWT, I'll probably barely make 300 rwhp.

[Jookmasta]

well when you order ur ecu, u mention ur entire setup as well as what boost level your planning on running................i told him 15 psi so i assume thats what he tuned for. nonetheless, yes this is stock internals. and as for dyno, didnt get a chance to dyno it before i left for school again.

[Jookmasta]

me running 15psi shouldnt be bad once the tune is dead on. the tunes have been proven as do remember that cory is also running the same ecu tune at 20-22 psi on his stock block............................and thats with a 50 trim t3/t4. yes its tru that the tune makes the world of difference especially when it comes to things such as longetivity of the engine. but as said before, the boost level was specified in the description of what to tune for. not much more u can do.

the btm would be a waste of money as if the ecu is retarding timing while in boost, a btm on top of that would super retard the timing, especially at 15 psi...........plus i trust the ecu to take care of my timing as that is one of the main reasons of gettin your ecu tuned.
Modified by Jookmasta at 2:50 AM 5/7/2006

[NateDogg]

Increasing boost shouldn't change A/F ratio because the MAF should keep adding fuel. This isn't a fixed number.

How much boost did he tune for? The timing is fixed, so either he was very conservative with timing or you have been very lucky.

I'd lower your boost back to what he tuned for before you blow your motor. Either that or add a BTM.

I assume your comments were directed at me..My point is that 480cc injectors are only good to 300whp, which seem small for 20psi on a T3, especially without any datalogging on the first run!!!

The MAFS can add fuel as much as it wants but if the injectors max out the duty cycle at 3V MAF reading you aint gettin no more juice at 4V! KABOOM! GALANGALANGALANG

[Jookmasta]

well needless to say, enough hating on the 20 psi pull lol. one pull and didnt really know what the level would jump to. nonetheless, 480cc injectors are not only good to 300whp. try checking the sticky for that info that proves that.

and yes this is on good old 93 octane ($3.17 a gallon )

[LEMHEAD16]

What is the AR on your tubro Jook?

[Jookmasta]

str8 t3...........60 trim compressor, .63 a/r exhaust internally wastegated..........

[crzycav86]

it's spelled straight btw.

and when you overboost while setting the mbc, you're supposed to let off.. not see how high it will go.

anyway, enthalpy is a good tune, but 480cc/min injectors are probably the smallest you'd want at 15psi with that turbo. According to the injector spreadsheet, the 480's are rated at 330 crank hp at 100% duty cycle. So you're pretty close to 100% duty cycle.

[S14tat]

sounds great, i really do wish that enthalpy made a real S14 ecu tune not some S13 ecu with a harness. but your very lucky that you didn't blow your headgasket at that boost level. cory ( nissanfanatic ) blew his at 17-18 psi. thats pretty much the only reason why i'm not running any higher boost then 1 bar.

edit: not to mention cory's 20-22 psi runs were all done on race gas. even his 18 psi run is done on race gas.

[Edub1]

me running 15psi shouldnt be bad once the tune is dead on. the tunes have been proven as do remember that cory is also running the same ecu tune at 20-22 psi on his stock block............................and thats with a 50 trim t3/t4. yes its tru that the tune makes the world of difference especially when it comes to things such as longetivity of the engine. but as said before, the boost level was specified in the description of what to tune for. not much more u can do.

the btm would be a waste of money as if the ecu is retarding timing while in boost, a btm on top of that would super retard the timing, especially at 15 psi...........plus i trust the ecu to take care of my timing as that is one of the main reasons of gettin your ecu tuned.

Modified by Jookmasta at 2:50 AM 5/7/2006

Let me try to explain a little better.

Unlike fueling, the ECU does not add or subtract timing via sensor. It has a spreadsheet of fixed values that the ECU looks to depending on engine load & RPM. What the tuner does is determine where the areas of this spread sheet will be under boost. Then the values in this area are altered. Take for instance the WOT, higher RPM columns. Assume this will be max boost. If you specify 14Lbs as your max boost, the tuner will pull say 9 degrees from this column.

The thing is, the map can only be set for one boost level at a time. So, if you add boost, the timing stays put and you will not have enough retard. Conversely, if you tune for 20Lbs but only run 7 you will have too much retard.

In the end, it is better to be conservative on timing as it will increase longevity, as will staying at about 250HP. If you want to adjust boost you can get a dual tune or use a BTM to pull extra timing when you surpass the max limit of the ECU tune. Of course a conservative tune should handle a few extra pounds for a few 1/4 mile passes. Use copper plugs, learn to read them and don't drive around like that. Don't go crazy with boost either. You might have just gotten lucky.

[Jookmasta]

well i didnt carry out that 19 psi pull to the redline as i set the warning meter for the 1.30 bar on the blitz gauge.

excuse the spelling as you are right, it is spelled "straight".

as for your post edub, thanks for the explanation. from reading on the forums, that explanation that you said is what i understood as to how timing is tuned for with an upgraded ecu.

i do use copper plugs and like i said, the boost is now down to 15 psi and pending on the nite time conditions, will rise to 16 psi. your right as reading the plugs is probably one of the standard things that anyone ka-t should know how to do. i don't plan on going crazy with the boost either as my goal for the car was simply 13's on the track with as little lag as possible.

as for luck, well i guess part of it was luck as i'm sure there have been plenty of people who have blown their engine or something has gone wrong at 19psi. ya its a good thing that the engine is still going after the whole ordeal.

the part about staying at 250hp will increase longevity though i dont agree with. longevity isn't defined by a certain hp level..........

[S14tat]

Let me try to explain a little better.

Unlike fueling, the ECU does not add or subtract timing via sensor. It has a spreadsheet of fixed values that the ECU looks to depending on engine load & RPM. What the tuner does is determine where the areas of this spread sheet will be under boost. Then the values in this area are altered. Take for instance the WOT, higher RPM columns. Assume this will be max boost. If you specify 14Lbs as your max boost, the tuner will pull say 9 degrees from this column.

The thing is, the map can only be set for one boost level at a time. So, if you add boost, the timing stays put and you will not have enough retard. Conversely, if you tune for 20Lbs but only run 7 you will have too much retard.

In the end, it is better to be conservative on timing as it will increase longevity, as will staying at about 250HP. If you want to adjust boost you can get a dual tune or use a BTM to pull extra timing when you surpass the max limit of the ECU tune. Of course a conservative tune should handle a few extra pounds for a few 1/4 mile passes. Use copper plugs, learn to read them and don't drive around like that. Don't go crazy with boost either. You might have just gotten lucky.

i would like to rebute that. cory ( nissanfanatic ) was using anthony's techtom to double check his timing when he over boosted to 31 psi. his timing went waaaay down from 23 degree btdc when running 9 psi down to 8 degrees btdc. how else would his engine have survived that? he went all the way to 120mph at 31 psi.

to further prove this, his timing went from 23 degrees btdc down to 18 degrees btdc when he went from 9 psi to 1 bar. so even though jwt doesn't do squat for timing when you add boost. enthalpy tuned ecu's somehow does.

[deviousKA]

Enthalpy's timing drops a little too much imho, but hey, its not like its some large endeavor to retune the ecus, he tunes them just like everyone else.

Your probably just a tad slim with that injector size, but timing should not be a problem as his maps load scales encompass a good amount of boost and continue to drop timing, basically to nothing. Enthalpy likes to set the ecus to run ~11.5 A/F any time the engine is in boost (1 psi, 20 psi, same), regardless of rpm. This is simple to do, but there is no need for as much fueling in some areas and there is more power to be had with appropriate tuning.

A JWT ecu does not have the load scales set to encompass as much boost, when you have passed this maximum load the timing will not drop any further than the last set of values on the map. This could be fixed easily with a retune. The JWT boards use a configuration to try to deter people from retuning their ecus (couple address lines are reconfigured), but they are still easily modified. Enthalpy uses a basic generic "skip" board like us open-info tuners and can be reflashed in a matter of seconds.

[deviousKA]

Oh and BTW, a techtom is not required to monitor the timing advance of your ka24de's.

All that you need is a $40-80 consult adapter and a PC. You can tap into all ecu data and monitor it in real time. You can even dump and examine your ecu tune with these devices, something a techtom will never be able to do.

[MarkEmark]

Enthalpy's timing drops a little too much imho, but hey, its not like its some large endeavor to retune the ecus, he tunes them just like everyone else.

Your probably just a tad slim with that injector size, but timing should not be a problem as his maps load scales encompass a good amount of boost and continue to drop timing, basically to nothing. Enthalpy likes to set the ecus to run ~11.5 A/F any time the engine is in boost (1 psi, 20 psi, same), regardless of rpm. This is simple to do, but there is no need for as much fueling in some areas and there is more power to be had with appropriate tuning.

A JWT ecu does not have the load scales set to encompass as much boost, when you have passed this maximum load the timing will not drop any further than the last set of values on the map. This could be fixed easily with a retune. The JWT boards use a configuration to try to deter people from retuning their ecus (couple address lines are reconfigured), but they are still easily modified. Enthalpy uses a basic generic "skip" board like us open-info tuners and can be reflashed in a matter of seconds.

I'm glad you brought this up, because I was just about to make a separate post regarding how exactly the ECU handles timing...

So is the ECU really that "static" as far as controlling timing goes? In other words, it doesn't deviate much (if) at all from the timing maps programmed into it, regardless of any other factors, such as the difference in air density between a 20 degree night and a 100 degree day, holding "load" constant (e.g., WOT, 4000 rpm, 4th gear)? It'd seem to me that it'd be able to run quite a bit more advance safely on a 20 deg. night compared to a 100 degree day.

The ECU changes timing based on load....what does, say, a JWT KA-T ECU use to measure load? Throttle positions sensor? MAFS voltage? RPM? Gear? I know it doesn't use boost because they don't ask you how much you plan on running....

Does the ECU at all change timing due to overly rich or overly lean conditions? (Of course, the stock ECU with a stock KA engine would not need to deal with anything but minor, insubstantial fluctuations from what is considered the ideal A/F)

Because rich conditions don't need as much timing advance because the mixture burns faster, does the ECU retard timing automatically if there's a really rich mixture; by the same token, will it retard timing if the conditions are overly lean?

How does the ECU function in conjunction with the knock sensor? I know that it takes readings from the knock sensor and automatically figures out what is too much knock, and if this value is reached, the ECU retards timing...but again, in WHAT manner does it do so if too much knock is detected? Is there some absolute value that once reached, the ECU quickly and abruptly retards timing, or would it gradually and progressively retard timing as the knock got more intense? From your description, it seems like it does not do the latter, but rather the former...

Also, from your description it seems like the ECU can adjust the A/F ratio based on boost pressure (or vacuum)...If this is the case, why does JWT not care how much boost you're running when they program your ECU? For example, my ECU is programmed for 50 lb/hr fuel injectors, cobra MAFS, but they didn't care what boost I was running. So, from the standpoint of a company who doesn't want their customer's engines to blow up, do they assume that the max amount of boost and power will be run for a KA-T with 50 lb fuel injectors, e.g., 15-17 psi and 350 bhp? If the timing maps are made such that timing is retarded as load increases, wouldn't JWT pretty much be guessing about the load at some RPMS? For example, they could be retarding the timing too little at 3000 rpm if someone's running a small turbo that hits a full 16 psi @3000 rpm; similarly, they could be retarding the timing too much at 3000 rpm if someone is running a larger turbo that doesn't hit full boost till 4000 rpm...

I should definitely get on the phone with a JWT tech and ask him about this, because I really want to know what the hell they do to their ECUs when they're "tuned"....I've called them before asking if they could give me the timing numbers they use for their different tunes, but being at school without my car, I couldn't give them some serial number they wanted on the ECU to answer that question...

[Jookmasta]

well u brought up some interesting points markemark, and i think that you should definitely get in contact with them to see exactly what they do or perhaps what they should do better.

also, do they ask you what turbo you are running when you get your ecu tuned by them?

[deviousKA]

Good questions MarkEmark,

So is the ECU really that "static" as far as controlling timing goes? In other words, it doesn't deviate much (if) at all from the timing maps programmed into it, regardless of any other factors, such as the difference in air density between a 20 degree night and a 100 degree day, holding "load" constant (e.g., WOT, 4000 rpm, 4th gear)? It'd seem to me that it'd be able to run quite a bit more advance safely on a 20 deg. night compared to a 100 degree day.

The timing will deviate from the map value only due to engine temperature (you hit the nail on the head here). There is a seperate set of values that will dictate an addition or subtraction of timing advance due to temp. when the throttle is open, and one for when the throttle is closed (2 seperate tables, maybe more). Full understanding of the ecus exact usage of these tables is yet to be determined (see some of the later posts at eccs.hybridka.com).

Enthalpy/JWT are either unaware of these values or do not care to adjust them. There are certain applications that can benefit from a modification to this temperature based timing adjustment, most of which falling under "performance" turbo applications when running high boost. An unintended change of 1-3 degrees can certainly be an issue, depending on when the car was tuned (temperature) and what not.

Knock is a little different I, I will explain below.

The ECU changes timing based on load....what does, say, a JWT KA-T ECU use to measure load? Throttle positions sensor? MAFS voltage? RPM? Gear? I know it doesn't use boost because they don't ask you how much you plan on running....

"Load" as commonly referenced when discussing a Nissan ecu is actually a base factor of injector pulsewidth (TP, Theoretical Pulsewidth). The ecu has calculated that this pulsewidth, theoretically, would provide a 14.7 (stoich) AF for that particular RPM and load point on the map (at a "zeroed-out" setting). RPM is static, TP is factor of a main global fuel trim setting (K number), airflow percentage, rpm, temperature, and throttle position acceleration (simplified). This theoretical pulsewidth will then pass through the interpolated map value (which trims to a different final A/F).

So, the TP has more purpose than being the "Load" axis of the fuel and ignition table, but it works quite well for this task. TP reacts similarly to a pressure (map sensor) in nature, and the two can almost be directly correlated in linear fashion as far as map axis is concerned. The higher the boost the higher the TP (load) value, so it really isnt that difficult. The only problem is that any time changes are made to the global trim settings > TP to provide a different injector pulsewidth (maf change, injector change, more boost) The TP axis scales must be adjusted so that they lookup the proper cells on the map with the (generally smaller) calculated TP.

**EDIT**^this paragraph is generalized to make it easier to understand, see below regarding different turbo chargers with same boost level.

This is really simplified and condensed, you might want to do some more reading on nissans TP (theoretical pulsewidth). We have actual nissan patent information to reference for this calculation but it is more than I could fit in here.

Does the ECU at all change timing due to overly rich or overly lean conditions? (Of course, the stock ECU with a stock KA engine would not need to deal with anything but minor, insubstantial fluctuations from what is considered the ideal A/F)

Because rich conditions don't need as much timing advance because the mixture burns faster, does the ECU retard timing automatically if there's a really rich mixture; by the same token, will it retard timing if the conditions are overly lean?

How does the ECU function in conjunction with the knock sensor? I know that it takes readings from the knock sensor and automatically figures out what is too much knock, and if this value is reached, the ECU retards timing...but again, in WHAT manner does it do so if too much knock is detected? Is there some absolute value that once reached, the ECU quickly and abruptly retards timing, or would it gradually and progressively retard timing as the knock got more intense? From your description, it seems like it does not do the latter, but rather the former...

The ecu does have some "feedback control" using the factory narrowband o2 sensor. This is used after a certain engine temperature and only in a certain (low load, cruise, idle) portion of the fuel table. It is unknown how much this closed loop function can actually alter the fuel maps/fueling, but it is hardly anything substantial.

It can be removed if desired, or even set to encompass more of the fuel map. The targetted A/F for these closed loop areas is also adjustable.

The Knock function is almost similar to the feedback control (closed loop) function, except that it does not actually modify the value from the timing table. After a certain amount of times that the ecu has passed its knock listening threshold, the ecu will actually revert to a completely different fuel and timing table altogether. The areas in the timing table that are prone to knock, are similar to the closed loop fuel areas (specialized offset), and both the main and the "knock" timing table will have these areas to tell the ecu to listen for knock. In order for the ecu to switch back to the main fuel/ignition table from the knock table, it must meet a certain amount of no-knock threshold samples within this knock prone area.

Also, from your description it seems like the ECU can adjust the A/F ratio based on boost pressure (or vacuum)...If this is the case, why does JWT not care how much boost you're running when they program your ECU? For example, my ECU is programmed for 50 lb/hr fuel injectors, cobra MAFS, but they didn't care what boost I was running. So, from the standpoint of a company who doesn't want their customer's engines to blow up, do they assume that the max amount of boost and power will be run for a KA-T with 50 lb fuel injectors, e.g., 15-17 psi and 350 bhp? If the timing maps are made such that timing is retarded as load increases, wouldn't JWT pretty much be guessing about the load at some RPMS? For example, they could be retarding the timing too little at 3000 rpm if someone's running a small turbo that hits a full 16 psi @3000 rpm; similarly, they could be retarding the timing too much at 3000 rpm if someone is running a larger turbo that doesn't hit full boost till 4000 rpm...

It is generally accepted that timing advance should be dropped in accordance to boost (psi), this makes it easy to discuss and understand. The nissan ecu uses calculated load similarly to other maf based systems. Believe it or not, calculated load via airflow calculation is actually much more accurate when determining the engines fuel and timing needs than a pressure reading. The calculated load will take into account the actual flow entering the engine (turbocharger based, in this case) rather than the boost psi it is providing, and thus two different turbos running the same boost level would actually place them differently on the tables as they should be. Certainly there are limits to to how much boost/airflow the ignition/timing maps can handle, I assume JWT looks at your general needs based your your basic specs, and provides something that should cover your needs. It is quite simple to adjust the settings for additional capability while at the same time suiting the customers possible lower-level requirement.

[deviousKA]

Here is a visual example of the 1991-1994 ka24de 240sx main ignition timing map. The Y axis is rpm and the X (very bottom) is TP (load) value scale as described above.

The cells of the table in red are the actual timing advance the ecu will provide at that particular TP and RPM point. The cells in blue are offset by 128 to indicate a "knock-prone" area to the ecu so that it starts listening for knock as described above. Subtract 128 from each of these blue cells for the actual timing advance the ecu will provide at that point, (unless it has decided to switch to the knock map).



Forget the description "boost" and the -0.XX Kg labeling as those are incorrect, and a poor translation of this particular software.

Here is the same main timing table in inverted 3D wireframe. Here I have set the software to view without 128(knock detect) offset.



You will see the indicator is at full (TP) load and 4000 rpm, 24 degrees btdc. If you are running a stock ecu without any sort of airflow alterations or ecu tune, and distributor set to base 20, this is the timing advance that you will have at 4000 rpm with any sort of boost.

Here is the oem knock map in similar fashion.



As you can see the timing of the knock map drops considerably, 16 dbtdc at 4000 full load.

These settings are completely adjustable to user desire, this full load point could be XX psi providing XX the timing, and knock functions can be removed or changed. All things you could easily do yourself, and with a little work, get your ecu setup extremely well for your application.

I put these example pictures up to possibly help explain but also to spark interest. Even if your not planning on doing any rom tuning yourself, you can download all of the information for free and explore the oem (or tuned) ecu settings.


Modified by deviousKA at 5:11 AM 5/8/2006

[crzycav86]

Awesome, man. Very enlightening.

[Edub1]

MarkEmark, the short answers are, there is a seperate timing map for knock conditions on equiped cars.

As far as atmospheric pressure changes and temp. This is mostly a fuel issue. Temp is addressed by the ECU (mostly for fuel enrichment) and pressure will not change things because the MAF reads actual air mass. There is a closed loop operation in which the ECU measures O2 emissions and adjusts fuel.

To answer your question more directly, these changes are small and none of these factors are going to call for the sweeping change in timing needed by a turbocharged motor.

If you really want to understand the ECU, there is much to know.

For our purposes, there is a spread sheet (map) that looks at RPM on one scale (Y) and a few things such as throttle position & MAF input (load) on the other scale(X). From these values it looks to a given column & row and reads the cell value.

Because it reads MAF input, fuel is handled dynamically. It is not necessary to handle timing this way because charge density doesn't vary that much for non-turbo motor. It is only when you increase charge density by a significant margin as with a turbo, that you need to pull timing.

So, the answer is that timing, for our purposes, is fixed and must be changed according to where boost will occur and how much.

I assume JWT has some general, safe tunes for most popular turbo apps. But, if they don't tune for a given boost level they will certainly lean toward the conservative side.

If you decide to tune yourself, you will have to determine where your car will come into boost and by how much it will be boosting at the related load V. RPM range. This can probably be done If you have a Consult ECU and with enough dyno time.

Or just use a BTM.

[BlackHat]

Quick noob question...

That table is for the advance right? Maybe I'm misunderstanding how advance works... but if I'm reading that table right, 4000rpm at full TP you have 24 degrees advance, but 4000rpm at low TP you have 43 degrees... Don't you advance more on hard throttle than when you're just cruising? And I guess that's the advance + base advance (of 20 degrees right?). That would me 44deg on full TP 4000rpm and 63deg on low TP 4000rpm....

I have to be reading this wrong...

[1WheelWonder]

Awesome Jookmaster makes me want to go the tuned ecu route.

[Craving4Boost]

thanks a lot for the update jookmasta...i cant wait to test my enthalpy tune.

[onosqv]

enthalpy's ecu allows you to run open atmosphere? did you have to request this specifically or are all his ecu's like this (he doesn't answer his emails quite as fast as u do ).