'88 5-speed dyno log
#436
What are your thoughts on making an 'S400' using a MAP type setup for the 928? I would love to ditch the MAF and go MAP.
Some obstacles I forsee:
-A newer, more accurate TPS must be used for the relationship between MAP, load and engine temperature
-Custom 'black box' that will require the MAP, TPS and Temp II sensors to connect to for communication.
While it may seem like more trouble, your maps will be significantly more accurate.
Some obstacles I forsee:
-A newer, more accurate TPS must be used for the relationship between MAP, load and engine temperature
-Custom 'black box' that will require the MAP, TPS and Temp II sensors to connect to for communication.
While it may seem like more trouble, your maps will be significantly more accurate.
If I get time, I would like work on a WOT adjuster for the S4 chips (possibly incorporating a bridged air temp sensor), but that's about it. An altitude switch would be nice, too. (WOT gets richer as you go higher.) I removed references to the coding plug in my S4 chips, so those inputs are available.
The LH has a variable resistance input in the coding plug (#4) plus a couple of switches (#2, #6). The EZ coding plug inputs has only switches (#7, #5, #3 might be variable, IIRC) but the auto trans shift retard input is variable.
Both the S4-up LH and EZ can accept variable resistance via the WOT input (LH idle too) so a real Throttle Position Sensor could be programmed to work without new wiring.
#437
Looking at some EFI books, volumetric efficiency is key to a well-running engine and optimized power. If a potentiometer type TPS is used, the voltage (or ohms) of the switch's output would be key to the LH gaining a more accurate measurement of the air swallowed into the intake for distribution into the cylinders.
However, how about intake temperatures? I don't know if the LH has the capability of measuring this in relation to mixture. There is the IAT sensor on the top of the 87-on cars, but I think that is mainly tied into the radiator fans. Intake temps are crucial also to proper mixtures. Can the PROMs be programmed to read the IAT sensor? Is it accurate enough for the job?
Lastly, wideband O2 sensors. Is the standard board capable of handling a 0-5v sensor rather than a narrowband 0-1v?
However, how about intake temperatures? I don't know if the LH has the capability of measuring this in relation to mixture. There is the IAT sensor on the top of the 87-on cars, but I think that is mainly tied into the radiator fans. Intake temps are crucial also to proper mixtures. Can the PROMs be programmed to read the IAT sensor? Is it accurate enough for the job?
Lastly, wideband O2 sensors. Is the standard board capable of handling a 0-5v sensor rather than a narrowband 0-1v?
#438
The intake sensor (S3/S4) is just a switch to turn on the radiator fan(s) only. No connection to the LH or EZ.
A WBO2 connection would be sweet. I would definitely try to program this if I knew how to input a voltage easily. WOT feedback, lean burn...
Except for the MAF and O2 sensor all the variable inputs are voltage dividers which expect a certain resitance range. I don't know what it would take to work with this. (Electronics are a still a black art to me, unfortunately.)
A WBO2 connection would be sweet. I would definitely try to program this if I knew how to input a voltage easily. WOT feedback, lean burn...
Except for the MAF and O2 sensor all the variable inputs are voltage dividers which expect a certain resitance range. I don't know what it would take to work with this. (Electronics are a still a black art to me, unfortunately.)
#439
The only other thing I'd like to do - if only for myself - is to let the LH to control the A/C compressor for a little extra torque on demand.
The LH has inputs for compressor-enabled (#14) from the freeze and pressure switches, and A/C-on (#15). (Both inputs do different things in the code.)
I already programmed the (unused) shift light output (#26) to go to ground when Sport Mode is active so the easiest would be to just connect a relay to it. (If the vapor recovery system is deleted, that solenoid output could be used, too.)
The LH has inputs for compressor-enabled (#14) from the freeze and pressure switches, and A/C-on (#15). (Both inputs do different things in the code.)
I already programmed the (unused) shift light output (#26) to go to ground when Sport Mode is active so the easiest would be to just connect a relay to it. (If the vapor recovery system is deleted, that solenoid output could be used, too.)
#441