I'm thinking about pulling my MAF and tuning my car for Speed Density (Open Loop) whatever Anyway's what all is involved? I know I have to raise the coolant temp to stay in open loop or whatever but is there anything else?

As far as tuning for it do I just log everything with datamaster and then run VE Master?

Also what does Speed Density use for tuning in WOT? Does it still use the PE Tables?

thanks

 

speed density still uses closed loop like the MAF sensor. all you do is go to the ECM switches and enable speed density mode.

next you wanna get VEmaster to get all your BLMs in line. WOT tuning is the same as before.. use the PE table.

why do you want to get rid of the MAF sensor?... its so simple compared to speed density.

 

Cause it seems to be an endless battle trying to tune these POS MAF's when they are ported. I know they are more restrictive when you leave them stock so i'm thinking about just removing it that way I can tune it easier and let VEMASTER do all the thinking..

So speed density has nothing to do with open loop or what? Why do people choose to run their car's in OPEN LOOP then? why not just use speed density for part throttle and then still use the PE tables for WOT?

PE Tables are NOT used in open loop correct?

Also when I tune with VEmaster should I run datamaster with the MAF plugged in or should I have it unplugged? Also when i log with datamaster should I have speed density CHECKED or UNCHECKED? or does it matter?

Someone needs to make a MAF Master or something that would be the $hit

 

I tried and tried to get my PCM tuned with a ported MAF but it was useless. Once I put stock ends back on the car ran like a dream. I even disabled MAF mode but getting the Speed Density tune was next to impossible. Plus when there was a wether change ( colder or warmer air, more or less humid) the SD tuning ran like crap. Good luck if you can get SD tuning doen, but it takes alot of time. I found going with stock MAF ends solved all my problems and the car runs great.......and I put over 400 HP to the rear wheels with stock MAF. Its not a restriction.

 

Open or closed loop only has to do with whether or not the O2 sensors are used to control fueling, making it richer or leaner based on the O2 reading and adjusting the BLM cell number above or below the "perfect" 128 reading for that rpm/tps combination. When in "open" loop, the BLM value of 128 is used all the time and fueling is not adjusted, uses whatever values are calculated from the VE and MAF tables with no consideration of the current BLM cell value, assumes 128.

 

If you have a good maf reading you can calculate your VE tables using


VE = ( MAF * (IAT + 273.15)) / (MAP * RPM * Displacement) ) * 212544


Where MAF is in g/sec, IAT is in Centigrade, MAP is in kPa, and displacement is in cubic inches (displacement of the whole engine)

here is the derivation
http://www.slowcar.net/VE.gif

This will give you VE in units of percent. If you really want to go SD, throw in a good MAF, calculate your tables, input those, then pull off the MAF.


That said I would stick with the MAF.

Chris

 

OK so when I run my log file in datamaster do i need the SPEED DENSITY setting CHECKED or UNCHECKED in the ECM SWITCH table? or does it matter? I know that to use the ve tables the computer needs to be in speed density mode but for logging purposes does it need to be?

 

What motor are we talking about?

 

LT1

 

you want to check it do enable SD mode. then youll need to get a very extensive datamaster log for VEmaster... the more variation and cell range you have for VEmaster, the better your results.