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Time based access TPSdot and ms pulse width


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Would anyone have a time based acceleration curve that they would be willing to share?

MS2 pcb3.57

Engine is a 2jz, but I think any L28ET or such curve would be great to just get an eye on. A screen shot or the 4 points typed out would be fantastic. I'm running a bit lean on tip in, so I need to up the ms of fuel added on accel, but I'm just not sure what ball park I should be aiming for and would be nice to have something to kind of go on.

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Here are some resources that I was directed to when I started to focus on AE.  For now I have gone with the method outlined in the first video and have gotten decent results.  




and a post by someone in response to my question


"Personally I use EAE, once you get it all set up I get the best results with it. With the stock settings and no tuning it will make your car run like shit. If you want something to get up and running quick, use time based or AE pump. If you have the time and dedication set up EAE and use AE pump for large stabs.

For EAE your going to want to do some pulls at ~ half you rev range, ie your car redline is 8000, do the pulls at 4000. Negate the coolant temp and RPM corrections

Slowly, but steadily roll onto the throttle until WOT, hold WOT for ~2-3 seconds, then at the same rate slowly roll off the throttle till your in overrun.

There are a few methods to do this, what I find best is this.

Added to Walls is the coefficient that tells the ECU how much fuel is sticking to the walls, there for it directly controls pulse width. If you tell the ECU more fuel is being stuck to the walls, it will increase injector pulse width to compensate. If you are rich on tip in, decrease this value, too lean increase this value.

Sucked from Walls is the coefficient that tells the ECU how much fuel is being sucked from the walls, it indirectly controls pulse width, If you tell the ECU more fuel is being sucked from the walls, it will decrease injector pulse width to compensate. If you are rich on tip out, decrease this value, too rich increase this value.

Once you have this settled for your current rpm range, tune the RPM modifiers then I suggest setting up a rough map in the coolant temp modifiers based on logic. More fuel is going to stick to a cool engine wall, etc. Then tune that as you would cold starts.

Once that is all settled you will find you can greatly reduce your Accel pump AE and really only utilize that for large quick stabs on the throttle.

Turbomiata has a few good threads on setting up EAE, honestly for MS stuff look into the miata community. They by far have the most experience with the system and the community is good about sharing reliable information.

If you are using EAE with a flex fuel set up, keep that in mind and realize you'll need to make some compromises on each base fuel for blends to work smoothly.

If you got any question let me know."

Edited by Namor
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Thanks guys, I am familiar with the resources, my problem is more or less just the scale at the moment. The resources seem to run a more archaic % based fuel enrichment rather than the increased pulsewidth ms based fuel enrichment that seems to be the modern norm or at least the norm in the newer versions. Watching the supra video for example I tried using the first point as a reference only to find that my chart won't allow anything higher than 25.5ms which is when I realized that the supra video is in %. 

I'll be giving it a shot shortly.

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The TPS Threshold  Box is the key to getting AE working correctly.. The Default figure of 200 is way too high. Try 10 to 20. Even though you can have the graph line set very low, If you don't change the Thresh hold value, all areas below the Thresh hold point ( Default = 200 ) will be ignored. First picture is of some Default settings. Second picture is what works to get rid of that " Tip In " stumble. 

Some engines also like a blend of MapDot... so you have to lower the default setting of 100 to about 20 as well.

Default TpsDot Thresh Hold at 200. Even though graph line goes down to 20.4..all of that will be ignored till TpsDoy gets above 200. Rather silly programming od software if you ask me. Two values to change when one would do. 

TpSDot = 200.jpg



TpsDot thresh hold configured to 15.0. Now the low end of the Graph is not ignored and Tip In stumble magically disappears. Note that Slider is all the way to the right to use TpsDot only. As mentioned. Some cars like a bit of MapDot blend as in the upper picture. But the MapDot thresh hold ( Not circled ) would have to be lowered as well. I just Luv default values that don't even come remotely close to what real world engines require Grrrrr.

TpsDot  = 15.jpg

Edited by Chickenman
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Thanks Chickenman, would those values happen to be for a roughly 3L displacement motor? It definitely helps to see somewhat of a scale.

Mine is set to 100% TPS for sure and I think 50 for the threshold. It was fluctuating a bit and kicking it on, I'm not sure if that is from turbulence or what not, I'll plan on lowering it a bit more and see if it has settled.



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On 9/25/2017 at 10:41 AM, Namor said:

Oh, I didn't realize that older versions of MS use a time-based PW adder instead of percent-based.  All I know off the top of my head is that my car idles somewhere between 1.5 - 2ms, with 450cc injectors.  


Btw, why do you think percent-based is archaic?  

Kind of, not in that it won't work or anything like that, just that the newer version doesn't seem to use it. Makes it harder to translate and apply. 

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The TpsDot threshold is mainly set from the amount of noise that you have in your system. How I tuned my L28 is by turning the accel enrichment off and data logging the car driving steady state speed on a flat straight road. The data log will record the MapDot and the TpsDot. You want to set your threshold above the steady state TpsDot value so that your enrichment isn't being activated when cruising. 


Granted, I am using a blend of TpsDot and MapDot. I chose to go with both  because of the lag of my turbo and boost onset when shifting gears. It was terrible with the larger exhaust housing I had on the turbo.

(Disclaimer, that may not be the correct way of fixing the problem. I'm a novice tuner)

Edited by lowrider
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On 9/27/2017 at 9:47 AM, seattlejester said:

Thanks Chickenman, would those values happen to be for a roughly 3L displacement motor? It definitely helps to see somewhat of a scale.

Mine is set to 100% TPS for sure and I think 50 for the threshold. It was fluctuating a bit and kicking it on, I'm not sure if that is from turbulence or what not, I'll plan on lowering it a bit more and see if it has settled.



Every engine is different of course. A lot of variables. But think of the TpsDot as the accelerator pump shot on a carburetor. Now, in general, Datsun L series are a lot like SBC in accel pump shot. Thye like a quick fat shot of fuel. So start the left side of the graph at about 15 -20 TPsDot and then adjust the slope angle . Should be fairly steep. BTW, that graph shown is fairly steep. Due to a bug in the code. The Y Axis will not scale lower than 48. Even though it will prompt you for a number between 0 and 25.5 if you try and set the minimum value. 

You can monitor the TpsDot figure at idle. It should be fairly close to zero. That is the only sensitivity level you should be concerned abou. Do NOT worry about the AE ( TpsDot or Map Dot ) coming in at cruise. It is supposed to. Think about a Holley accelerator Pump cam system. There is absolutely no delay at cruise when pump shot AE  comes in. Any slight " Tickle of " the throttle will initiate some AE enrichment. And that is how it should be. Tip in at Cruise is often the hardest part for people to understand. You have to have IMMEDIATE AE, because you are already running lean mixtures and a low throttle angle. So any slight opening of the throttle " Or Tickle " will require an immediate increase in AE. 


I had a perfect example the other day when I installed a new Tune on a local car. Car was originally Pig rich, idle was near 10.0 AFR and cruise was in the 12.0 AFR range. After loading a " proper " tune engine idled smooth as silk at 13.8 AFR ( mild cam ) and cruise was dead smooth at 15.0 AFR. On problem was a  stumble at Cruise Tip in and just off idle. This wa due to the TpsDot Thresh hold being to high. Customer mentioned that it never did this on the old Tune. Reason was he was running so Pig rich that ZERO AE was needed at any speed. When you lean things out to get efficiency and fuel economy, AE " Tip in" plays a big part in obtaining smooth driveability. Full throttle AE is dead easy to set up. It's subtle little roll on or " Tickle " of throttle that is hard to get right. That you just have to play with, on the left side of the scale. 


The area between idle and 1,500 RPM is alo very important as a " Tip In" transition zone. Don't get it too lean. Should be under 14.0 to one with a stock engine. Around 13.5 to 13.8 with any decent Camshaft. 

BTW, 25.5 ms of extra fuel is the Maximum value that you can add.

As stated in the Scott Clarke video. Your first value should be a minimum of double the idle pulse with. A big camshaft will want more. As will a bigger TB. Send me you Current Tune.msq and I'll have a look at it for you. 

Edited by Chickenman
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Appreciate the offer. 

Let me take a stab at it first before I embarrass myself. The tune is off of the 7m motor so there are probably differences especially with this bigger turbo pushing more air.

Current plan will be to run the VE analyze live and dial in the background map, then adjust the AE. Will post results and screen shots, and Chickenman I'll be sending you the tune to see if there are any spots you can see that are problematic.

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Juts remember to leave the AE and EGO control enabled. It's a myth that you have to turn them off when running Auto-Tune. Old wives tales back from the days of the original B&G MegaTune. Since Tuner Studio has taken over tuning development, there are Automatic filters in place to compensate for the AE and EGO controls.

I like to make the VE Cells in the high boost areas about 10 to 20 % richer over what the MS VE Table generator calculates. Auto-Tune cannot compensate fast enough to correct a lean condition at WOT and high boost. Melty, melty. Where-as if you set the High Load areas purposely rich, Auto-Tune can pull the values down at it's leisure. No harm no foul. GL with your Project. 

Edited by Chickenman
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I bothered a friend who did a lot of autotune on his 2.7L engine with the same turbo although different engine, his car drives nice enough that he daily drove it in the summer. His AE values are quite a bit lower than mine or the ones in the picture you have were set to. Might be he is running bigger injectors or the values or more built into his table. His VE table is drastically different then mine. I honestly don't know what to go off of. I did play around with the generator for what I kind of expect the engine to make even at a modest 300hp at 6krpm and 300tq at 4krpm, it is way way different than mine. Honestly I think it has been so long and I copied and looked up so many thing I fear I might have taken values that don't make sense. 

I for some reason recall that VE shouldn't really go above 100, but at the same time, I believe on boosted cars the VE is higher since the boost. I wonder if that thought is from an NA perspective.

Your thoughts would be appreciated I am planning on consulting a tuner locally, found one that is willing to work with MS, but I also don't want to bring a car that needs a ton of work.


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It is really flat now, it was a bit more aggressive, but when I was looking at my friends tune and playing with it I wrote his values in. I think his has more fuel via the VE table so he doesn't need as much in the AE. 

Thanks for that I will take a look. 

The problem was when I was trying to play with it via how the video said, the initial response was going rich even with a low curve, I don't see how I can not add any fuel other than taking it out of the map, so I think the map needs a bit more adjustment before I start playing with the AE. The problem with that is that even with the autotune enabled it is getting no where near what the generated VE table looks like. 

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Brian. Which engine is that . The 2JZ I'm assuming by size. 3.0L

Generated VE table can be crap as Steve mentioned. . Very dependant on inputted values, and even when those are correct it can be as much as 20% lean on the Top end and 20 % rich on the bottom end. It is very much an approximation...

Setting Idle AFR manually is necessary om most cars, especially ones with a larger camshaft. I don't allow Auto Tune to touch the idle setting as it usually screws it up. I usually set Minimum VEAL RPM at 200 RPM above idle. Same with EGO control. This is absolutely necessary with bigger cams. 

The reason this Tune has minimal AE, is that I have a feeling that it is running very rich at idle and just off idle. Probably 12.5  to 12.0 or richer.  Common with big injectors. It can be hard to get the Pulse Width down low enough to get a good idle AFR ( more difficult with Batch Fire ) . Which should be usually end up at 13.6 to 14.0 with Batch fire and a stock cam. 13.8 is a good starting point. Big cams like the 13.0 to 13.5 AFR at idle range. 1st step off idle to 1,500 rpm should be very close to the idle calibration. This will smooth Tip in response from a stop and at cruise.

If the main Fuel Table is rich all over... you don't even need AE and the car may run surprisingly smoothly. It will be swilling fuel though and money will be flowing out the Tailpipe. Once you get an ideal AFR ratio dialed in... and that means Cruise AFR's of 15.0 to 15.5 ( or higher with CDI Ignition ), THEN you need more AE. 

He is also running a TON of ignition advance down very early. Turbo cars like to do this to build boost quickly and to combat low CR, but in this case I think it may be excessive.  Again, I'm thinking this car is running really rich down low and that is preventing low rpm detonation. But done improperly, it can  also make the Turbo lazy.  Once you lean it out a bit, you can back off the amount of low end advance. If you don't, the engine will be fighting itself one you get above the 1,500 rpm range because the flame front will burn quicker when closer to Stoich.  Flame propagation speed is affected ( slowed )  by excessively Rich and Lean mixtures.

I'd like to see some datalogs of idle and cruise if possible.... 



Edited by Chickenman
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Sorry just to clarify, the AE table is off my friends tune (I'll see if I can find my previous curve I was running), my tune is attached. So my VE values, AFR, Timing, etc, his AE table (car has not been flashed with this, something I am just playing with).

My friend's engine is a 2.7L BMW engine which I was looking at the VE values from for comparison. 

The tune attached on my post is my engine with his AE table 3.0L 2JZ which has the VE values all below 100, which the VE generator was making a table with over half the chart above 100, which was causing me concern.

Will disregard and work with what VEAL is outputting. Thanks, I was getting a little concerned that there is a mismatch, but the few times I've run VEAL it did not seem to bothered by it.


Hmm these are factory injectors, but I will take a look at my log and see what it is idling at. 

I think that is what my friends tune is based off of how low his AE values are. My car is cruising pretty lean for my tastes, but I was educated in AFR's on a very broad basis so that may be quite off.

My timing table I believe is pulled from this forum so it might have been to combat the low L28ET compression if my memory serves where I pulled it from. 

I am pretty sure I took some logs with my old AE curve with a small drive and playing with the throttle in anticipation of digging through the file a bit, let me pull it off my laptop and upload.

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One of the strange things about Tuner Studio is how they used Req-Fuel. Required fuel in most other systems is a calculation for the Master Pulse Width.  That is a multiplier factor. Then other enrichments such as AE and WUE are calculated separately as Additive factors.

Tuner Studio has combined both the PW multiplier and Additive enrichment factors in the Req-Fuel calculation. This is a bit of a programming shortcut, but it does have one undesirable effect. Often the Req-Fuel calculation is too large, especially with larger injectors. What this does is to create low RPM and Load Cells with very low values. This affects your resolution.in Tuning ability. IE; Go from a 10 to a 9 in an idle Cell, and that is a 10% change. Go from a 50 to 49 and that is only a 2% change. The VE cell values are just Hexadecimal numbers in Tuner Studio. They do not really represent a VE scale. They can be any where from 0 to 255. In fact it is desirable to have larger numbers to increase Cell resolution.

To do that, some Tuners reduce the Req-Fuel Calculation by a percentage and recalculate using the VE generator ( Or manually increase the whole VE Table by the same amount the Req-Fuel calculation was reduced ). This has the desirable effect of increasing the low RPM VE cell values to a higher value that gives better resolution when adjusting up and down. The overall fuel end value doesn't change, it's just how the tables are altered. It's all just numbers in an equation. 50 x10 = 500 is the same   as 25 x 20 = 500.

The problem with how Tuner Studio has done things is that they have thrown the PW calculators ( Multipliers )  and the Enrichment values ( Additives ) all into the same equation. Change the Req-Fuel to a lower value, because you've installed larger Injectors, and it also changes most of the enrichment calculations. That's why other manufacturers keep the two calculations separate.  Now, you could just lower the whole VE Table by a set percentage... but then you may run into the Low Cell resolution at low RPM problem again. 

Because Enrichment values are included in the Req-Fuel calculation it makes comparing enrichment curves ( and tunes in general ) very difficult. Lower Req-Fuel values mean higher enrichment values to get the same end result compared to a Tune with a Higher Req-Fuel amount. It's all a matter of Table scaling, but it's a PITA that Tuner Studio did it this way..... IMHO 



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Here's a quote from a long time Tuner at MSExtra Forums taht maybe explains the Req-Fuel scenario better than I have.


I think you have a misunderstanding of how REQ_FUEL and the size of the VE values work.

First off, the VE values in your table are not real VE. It's possible (and desireable) to use the full 8 bit resolution of the VE table on an n/a engine, and have values of 200 and higher. this is not related in any way to your duty cycle, although the actual PW calculation gets part of it's value from there.

The req_fuel is basically the base pulse-width that all of your enrichments, corrections, VE values, load, etc. get calculated into a final pulse-width that you see on a running engine. The manual probably needs to be updated - I believe the idea of keeping values in the range of 8-16 was because of an old firmware that could cause damage if you went too far outside these ranges. also, I believe warmup enrichments are a % of your req_fuel, so keep that in mind if you do any changes there.

Now - if you are saying that the highest VE you have in your table is 100 (or close to it), and your req_fuel is 22, this just means that your req_fuel is too high. What you want to do is minimize req_fuel as much as possible, in order to gain as much resolution as you can in your VE table. If you are only seeing values of 100 in your VE table then I bet at low load/RPM areas you are in the single digits, and it's even worse if you turn off multiply map. 

This is bad for tuning - it's impossible to accurately tune when the smallest possible change is 1, and your VE values are less than 10 (that's a minimum 10% change in fueling for moving the VE up or down by 1). I wouldn't worry about using small req_fuels too much either - lots of people have successfully tuned with a smaller req_fuel to gain more resolution. I'm currently using a req_fuel of 2.4, with multiply map enabled my VE values range from ~60 to 240. That's lots of resolution.

Here is what I recommend you do - save a backup of your MSQ since you just got it running decently. Open your VE table, go to Tools - VE Specific - Table Transform. You can safely cut your req_fuel in half and double your VE resolution, so I would enter 11 as your new req_fuel. save it and it will automatically rescale your VE table - your max VE value should be around 200. if you're comfortable, you can make your req_fuel even smaller - I like to leave a little margin at the edges, so try not to go much over 240-250 as your max VE. 

Keep in mind you may need to do some tuning on your warmup enrichments after doing this - I haven't experienced any ill effects after dropping my req_fuel however.

Super MS/Extra'er
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