ive been trying to figure out how i can get AE TPS in faster because i have a huge lean spot when i open the throttle and when the ae actually gets delivered its wayy too much. you would think its too much MAP AE and not enough TPS ae but it isnt. ive been tweaking AE for over a year and i cant get it right. if anyone knows the filter i need to be changing i would appreciate it. i just need to get TPS AE in ALOT faster, i think i could be using alot less TPS AE if i did. i know when i was running $42 and $99 it didnt need much AE over stock and this is the same motor

thanks

 

The TPS AE and MAP AE are best used seperately. There are two parts to the AE equation. The first part is fuel wetting that ocurs when the MAP suddenly rises above the vapor pressure of the fuel. If the temperature is cool enough, the fuel will settle out onto the manifold walls rather than enter the cylinder like it should. This obviously causes the engine to go lean. This is mainly a function of the intake manifold temperature and manifold pressure (MAP). When the manifold is cool, the fuel will readily settle out. Hot, and no fuel will settle out. In between there is a transition region as only some of the components in the fuel can settle onto the walls, but not others. There is also an inverse where the fuel flash boils on a throttle closing, but we'll leave that aside for now.


The TPS AE is for the sudden inrush of air on a throttle opening. The manifold itself, on a throttle opening, will rapidly fill with air. The size of the throttle body and the ammount of throttle opening dictate how rapidly the burst of air will enter. The fuel calcs in the PCM will not take this into account, and youll get a momentary lean spot. The engine will hesitate for about 1/4 of a second, and then go normally. The TPS AE allows you to add fuel during a throttle opening to offset this. You should set the filters to nearly 255 (or unity if there is a conversion factor specified in the XDF) so that the TPS AE is very short. Then, increase the ammount of fuel delivered until the momentary lean spot goes away. The TPS AE comes in instantly (or no more than 12.5 msecs), so there is no real issue of it not being delivered quickly enough, just insufficient fuel volume.

It sounds like your currently trying to use the TPS AE to cover for some of the MAP AEs job, which is why your having a lot of trouble. The long term AE is not a function of the TPS directly, only MAP.

 

your absolutely correct here, but i have to add TPS ae to get enough volume out of it but it last so long it nearly floods the engine after tps ae is over.. i think (if its the right thing) my tps filter is set at 1. for map AE ive had the best luck tuning it in OD with the converter locked because you can get a huge MAP jump with very little tps change. and tuning it for hard upshifts. map AE is pretty good. anyone have any adresses for filters? thanks

 

thistable is set at 10.2 %
Title: TPS Filter Coefficient
Location: 48BF
units:% TPS
Address:48BF

and this table is set at 0.1 sec
Title: Execution Time to Filter MAP/ TPS AE
Location: 48BE
units:Sec.
Address:48BE

only filters i have found

 

You may still want to avoid running the TPS AE. I ran an RPM airgap, which is basically as bad as it gets, and the MAP AE, when properly tuned, was enough to compensate for all teh needs, and that was with a stick.

It sounds like you may want to up the volume of the MAP AE at higher delta MAPs, and increase teh nemerical values of the filter coeffs. This will result in a stronger, shorter pulse of AE. As for the TPS. Set the coeffs. to around 250 or so. This will make it last only a moment if you have a momentary flat spot on tip-in. IIRC, you can get a good deal of AE out of it by manipulating the cool temp compensation multiplier. One thing I have seen is inconstant units in the difinition of the AE PWs in the XDFs. This can cause the impression of more AE than you actually have.

I have all teh AE addresses defined in a hack that I can post later, although they should be in the XDF that your using.

 

im using the latest XDF from 93v8s10, i cant remember the name of it off the top of my head. but i will try raising the values. one question tho. i have a BBC TBI and performer RPM intake. if im in neutral and i floor it until 4000rpm or so and let off it will nearly stall and huff smoke for a few secs and pick back up. this tells me im way rich on ae. but if i decrease AE i get a big lean pop from the tbi. ive never had this issue with any other ecm. maybe im overlooking something or blowing it out of proportion. i would be willing to send you my bin if you wanna take a peek and do some comparing to bins of your own, as far as ae goes. i know they will have different needs being we have different setups, but it could give some ideas

 

adresses would be good tho. thanks

 

Here are the addresses and tables:

 

thanks, i saw that first table but didnt know iif it was related to AE at all

 

This came from RBob: "The purpose of the filter tables is to create the delta MAP and delta TPS values. The smaller the filter value the larger the delta. This is important to understand as it affects three areas of AE.

Remember that the smaller the filter value in the table the sooner, larger, and longer lasting the delta MAP/TPS value will be.

In the end the filter values affect three areas of the AE functionality: the threshold for AE, the volume of AE, and the duration of the AE."

I find that by significantly reducing the filter values it greatly helped my bog. Now it is nonexistant. 7.4L TBI with larger intake runners(Holley Projection).

 

thanks! that helped alot. when i ever get my body back together i will try playing with the filters. im in anti-rust mode right now. i will be shure to let you know what happens

 

the only filters i see that you posted are the MAP filter and that is listed under the DFCO parameters in my XDF. am i missing something? and the TPS filter coefficient only controlls TPS AE(volume) vs Temp correct?

also Location 48BF is a TPS filter but its shown in % tps. what exactly is that used for?

 

The cool temp based TPS filter coeff. controls the filtered TPS based on the engine cool temp. The filtered TPS is subtracted from the current TPS to get a delta value, which is then used to look up the injector firing time for the AE. This may not be defined in your XDF. Do you have the latest one?

The filter coeff. at L48BF is for the slow filtered TPS, and is not used in the AE calcs per se. Its more used for determining if the throttle position is stable for things like DFCO, baro updates, and EGR.

 

yeah its the latest one, i got it from 93V8S10. its ok, i know now. thank you. i was looking and i had actually increased the values in the TPS vs cool Temp table in alot of areas for some reason, not really shure why. i halfway remember doing it to lean out TPS ae in the cool temp areas. now that i know what the table is actually for i will cut the values way back and see what happens. thanks alot