A community of enthusiasts dedicated to Nissan's SR20DE/SR20VE/SR20DET engines.
Start here: forum search. Be sure to search on what you're looking for before posting a new thread.
You are currently browsing the forum as a guest. In order to access special features, the image gallery, and post you will need to be a registered member. Registration is fast, simple and absolutely free so please, join our community today!
If you have any problems with the registration process or your account login, please contact the administrator.
This is a question for you or anyone who can answer. I bought a Daughterboard + Consult interface from you a while back for my sr20ve. It was the one you package which is DE maf, VE inj, SR20VE tune.
It should be 8200. If you have a rom burner just read one of the roms directly, if not use the consult connection and dump the rom. Use rom edit to see what the limiter is set to (and adjust it to where you want it).
__________________
All posts by Calum in this thread are copyrighted by Calum, and cannot be edited, deleted, or copied without his express permission. calum@calumsult.com
The ecu can only count to 8000. If I was to rev to 9k the ecu will stop counting at 8000 rpms and just sit at 8000.
If your rev limiter is set at 8200 there wont be a rev limiter since the ecu stops counting at 8000. It never counts up to 8200 to trigger the rev limiter.
Is there any way of getting around this brick wall of fuel mapping on our ECU's with something like a Super AFC?
To be specific, yes the ECU doesnt recognize anything past 8000 or whatever it exactly is...... but with an AFC ( be it super AFC 1, 2, or the new AFC Neo) could it still be possible to correct the A/F ratio with other necessary tools ( aka wideband or whatever you want to use) after this drop off point of the nissan ECU.
__________________ 1993 NX2000
Last edited by JimmyNX2000 : 07-25-2006 at 06:40 PM.
Is there any way of getting around this brick wall of fuel mapping on our ECU's with something like a Super AFC?
To be specific, yes the ECU doesnt recognize anything past 8000 or whatever it exactly is...... but with an AFC ( be it super AFC 1, 2, or the new AFC Neo) could it still be possible to correct the A/F ratio with other necessary tools ( aka wideband or whatever you want to use) after this drop off point of the nissan ECU.
Is there any way of getting around this brick wall of fuel mapping on our ECU's with something like a Super AFC?
To be specific, yes the ECU doesnt recognize anything past 8000 or whatever it exactly is...... but with an AFC ( be it super AFC 1, 2, or the new AFC Neo) could it still be possible to correct the A/F ratio with other necessary tools ( aka wideband or whatever you want to use) after this drop off point of the nissan ECU.
If you get the signal through the ecu Your afc will only see what you ecu is seeing. This might stop at 8000 also. What I am thinking is grab the signal from an msd box or coil. Maybe it will show higher rpm.
Note: I have the blitz meter. Inj ms will stay the same when it passes 8000. 12.7ms at 8000 its 12.7 at 9000. timing will also stay the same.
If you get the signal through the ecu Your afc will only see what you ecu is seeing. This might stop at 8000 also. What I am thinking is grab the signal from an msd box or coil. Maybe it will show higher rpm.
Note: I have the blitz meter. Inj ms will stay the same when it passes 8000. 12.7ms at 8000 its 12.7 at 9000. timing will also stay the same.
If you get the signal through the ecu Your afc will only see what you ecu is seeing. This might stop at 8000 also. What I am thinking is grab the signal from an msd box or coil. Maybe it will show higher rpm.
Note: I have the blitz meter. Inj ms will stay the same when it passes 8000. 12.7ms at 8000 its 12.7 at 9000. timing will also stay the same.
The AFC or whatever else will still see RPMs past 8000rpms. Its the ecu that is hardware limited at 8000.
CALUM, why don't you chime in again here since you DO have first hand experience with the CODE in the ECU and with modded ECUs?
We have been talking about this every 3 years or so it seems and we have never had a conclusive answer to this.
Lets recap:
FACT:
Our ECUs are based on 16-bit processors. There is NO "hardwired" 8000/8012/80-whatever limit in the strict sense.
FACT:
the actual tables in the ECU do go up to a limit but it is NOT 8000/8012/80-whatever. It is lowert than that. The ECU from there on works with this "limit" and any other fuelling needs come from "enrichement" factors. In this sense, all reported above observations of 8000 rpm may/must be some restriction on the "reading" hardware/pins/software.
CHOADERBOY did verify that there is such a limit in a thread years ago but the final "verdict" was that it was probably a limit due to the SPEED of the processor, not the code or the architecture. We had "concluded" that the CPU in the ECU running at #.# MHz could not perform all the necessary fueling/timing/etc. calculations and operations in the available time when at/beyond 8000 rpm.
EXXD and SUPERCOWBOY report COnsult/Blitz sitting on 8000/8012 respectively no matter what the actual rpm is... this is considered a FACT as well.
SO, the real question is... CALUUUUMMMM... from your experience, have you seen such a limit anywhere in the code/data of our ECUs?
If you get the signal through the ecu Your afc will only see what you ecu is seeing. This might stop at 8000 also. What I am thinking is grab the signal from an msd box or coil. Maybe it will show higher rpm.
Note: I have the blitz meter. Inj ms will stay the same when it passes 8000. 12.7ms at 8000 its 12.7 at 9000. timing will also stay the same.
This is what I figured.... So heres an idea..
So lets say we can somehow tap the signal into an AFC from the ignition via MSD ( which really isnt a big deal because we are talking VE here and as far as i know its necessary in some cases) , From there we should be able to monitor/correct correctly... good.
On the note of injectors maxing out... that can be picked up from other readings( aka a wideband like I mentioned before) You should easily be able to pick up where the injs max out.
