mastacox
04-06-2007, 05:44 PM
Alright, time to jump right into the thick of it and add some supercharger tech in here. For those that don't know, I have a 1998 Toyota 4Runner SR5 with the Gen 2 TRD SUpercharger, and URD's 3.4l Supercharger Fuel Upgrade Kit (http://www.urdusa.com/product_info.php?cPath=79_80&products_id=1230100017).
Why I added the Fuel upgrade kit is a very long story, but suffice to say no Supercharged 3.4l is safe without it. Stay tuned for detailed descriptions of exactly why and how in the Supercharger Section of the Toyota WIKI in the coming weeks. TRD 3.4l Supercharger WIKI (http://www.ultimateyota.com/index.php?option=com_openwiki&Itemid=60&id=wiki:trd_3.4l_supercharger)
Sorry for the book, but I'd like to try documenting some of my tuning efforts. Just so everyone is clear, all of this tuning is being done in Los Alamos, and the highway between LA and ABQ. Elevation is anywhere from 5500ft ASL to 7800ft ASL. There are lots of big hills between the two which are excellent (and horrible) for inducing ping, so usually if I hear ping it's in top gear under high boost going up a 6-10% grade.
With my fiance's help I have semi-successfully made myself the beginnings of a "Summer Tune" fuel and timing map. She has gotten very good at driving for me while I sit and stare like a little nerd at the computer screen, trying to spot problem areas. I have decided I definitely need to make a little momentary switch connection for ECU power for easier resets though (I'm copying you Mark), as I have been pulling the ECU fuse after each modification to the map. For this new summer map I pretty much started from scratch, and have embraced a few functions in the tuning software, specifically the "fill cells with X" and "adjust by X%" buttons.
Strangely, as things have been starting to warm up, I actually began experiencing ping again in the mid-to-high boost region (3-5psi on the boost gauge, but more like 1-3psi absolute) at 2000-2500rpms. This was a bit of a surprise to me since I hadn't had any ping all winter after I upped my timing retard to 6.5deg in some spots. I had to up the retard to about 7.2deg IIRC in order to fully eliminate it again. Perhaps from the winter/summer blend gas switch? Winter blend gas has more ethanol in it, it may have a cooling effect on the intake charge helping with ping in the same way a WMI system does. Anyway, I really need to take a long hard look at my timing map this summer because I get the feeling it just covers WAY too much area, and the only way to tell if I need retard in a specific spot any more is to lower the retard and see if it pings, which is a time-consuming process to say the least. Still, better safe than sorry I suppose. I may be interested in that "knock sensor light" you mentioned for something a little more accurate in detecting problem areas.
As for the fuel map, I have pretty much revamped it and have had pretty good luck at keeping the most of the long-term fuel trims near zero for closed loop operation (they usually hover around -0.8 to +0.8). I discovered a very useful feature in the tuning software is the "change cells by X%" button, because the fuel trims are also a percentage value. So I can take a look at the long-term fuel trims in a selected area, select the cells that I want to change by using [shift] highlighting, and chage them by the fuel trim's value (say -6% for example). This really has made tuning closed-loop much easier.
My current map is actually much more uniform than my original one, it seems to me that fuel map values are largely independent of the amount of boost applied (thanks to the FPR mod perhaps?) So looking at a specific RPM row, the values accross it are all the same, until I pass into boost and open loop. As a matter of fact, all of the values are the same from about 2000 rpms to 6500 rpms (I know that's way past redline) and -25inhg to 0inhg/psi, that value being 9.2 IIRC. When I pass into boost, the values decrease to 9.1 for under about 3000 rpms, and above 3000 they stay at 9.2. I have yet to tune open loop, but I suspect they will need to be decreased to 9.1 or even 9.0 because I am running at about 10.0:1 in open loop hard throttle right now.
On another note, the fuel map values at idle ended up having to be much different. I have them set at 9.8-9.9 from 500rpms to 1500rpms in vacuum after some warm-start and open-loop idle testing. I don't have it perfect yet (and I'm not sure I ever will) but I have helped alleviate many of my problems for warm-start lean conditions and cold-start lean conditions (as well as open-loop idle after heavy throttle applications, which is kind of unexpected). Getting the idle just right is the hardest part by far, but worth the effort. It is also difficult because I need to think about tuning open-loop engine decleartion (engine braking) where I'm running at about 12.0:1 (and have been ever since I installed the URD kit and wideband stuff) and I would prefer it to be closer to stoich. Problem is, some areas between idle and engine decel overlap and idle will have to take priority.
So that's what I've done thus far. It's a long read, but maybe some of my experiences will help you in yours. Expect updates as I continue tuning throughout the summer.
Why I added the Fuel upgrade kit is a very long story, but suffice to say no Supercharged 3.4l is safe without it. Stay tuned for detailed descriptions of exactly why and how in the Supercharger Section of the Toyota WIKI in the coming weeks. TRD 3.4l Supercharger WIKI (http://www.ultimateyota.com/index.php?option=com_openwiki&Itemid=60&id=wiki:trd_3.4l_supercharger)
Sorry for the book, but I'd like to try documenting some of my tuning efforts. Just so everyone is clear, all of this tuning is being done in Los Alamos, and the highway between LA and ABQ. Elevation is anywhere from 5500ft ASL to 7800ft ASL. There are lots of big hills between the two which are excellent (and horrible) for inducing ping, so usually if I hear ping it's in top gear under high boost going up a 6-10% grade.
With my fiance's help I have semi-successfully made myself the beginnings of a "Summer Tune" fuel and timing map. She has gotten very good at driving for me while I sit and stare like a little nerd at the computer screen, trying to spot problem areas. I have decided I definitely need to make a little momentary switch connection for ECU power for easier resets though (I'm copying you Mark), as I have been pulling the ECU fuse after each modification to the map. For this new summer map I pretty much started from scratch, and have embraced a few functions in the tuning software, specifically the "fill cells with X" and "adjust by X%" buttons.
Strangely, as things have been starting to warm up, I actually began experiencing ping again in the mid-to-high boost region (3-5psi on the boost gauge, but more like 1-3psi absolute) at 2000-2500rpms. This was a bit of a surprise to me since I hadn't had any ping all winter after I upped my timing retard to 6.5deg in some spots. I had to up the retard to about 7.2deg IIRC in order to fully eliminate it again. Perhaps from the winter/summer blend gas switch? Winter blend gas has more ethanol in it, it may have a cooling effect on the intake charge helping with ping in the same way a WMI system does. Anyway, I really need to take a long hard look at my timing map this summer because I get the feeling it just covers WAY too much area, and the only way to tell if I need retard in a specific spot any more is to lower the retard and see if it pings, which is a time-consuming process to say the least. Still, better safe than sorry I suppose. I may be interested in that "knock sensor light" you mentioned for something a little more accurate in detecting problem areas.
As for the fuel map, I have pretty much revamped it and have had pretty good luck at keeping the most of the long-term fuel trims near zero for closed loop operation (they usually hover around -0.8 to +0.8). I discovered a very useful feature in the tuning software is the "change cells by X%" button, because the fuel trims are also a percentage value. So I can take a look at the long-term fuel trims in a selected area, select the cells that I want to change by using [shift] highlighting, and chage them by the fuel trim's value (say -6% for example). This really has made tuning closed-loop much easier.
My current map is actually much more uniform than my original one, it seems to me that fuel map values are largely independent of the amount of boost applied (thanks to the FPR mod perhaps?) So looking at a specific RPM row, the values accross it are all the same, until I pass into boost and open loop. As a matter of fact, all of the values are the same from about 2000 rpms to 6500 rpms (I know that's way past redline) and -25inhg to 0inhg/psi, that value being 9.2 IIRC. When I pass into boost, the values decrease to 9.1 for under about 3000 rpms, and above 3000 they stay at 9.2. I have yet to tune open loop, but I suspect they will need to be decreased to 9.1 or even 9.0 because I am running at about 10.0:1 in open loop hard throttle right now.
On another note, the fuel map values at idle ended up having to be much different. I have them set at 9.8-9.9 from 500rpms to 1500rpms in vacuum after some warm-start and open-loop idle testing. I don't have it perfect yet (and I'm not sure I ever will) but I have helped alleviate many of my problems for warm-start lean conditions and cold-start lean conditions (as well as open-loop idle after heavy throttle applications, which is kind of unexpected). Getting the idle just right is the hardest part by far, but worth the effort. It is also difficult because I need to think about tuning open-loop engine decleartion (engine braking) where I'm running at about 12.0:1 (and have been ever since I installed the URD kit and wideband stuff) and I would prefer it to be closer to stoich. Problem is, some areas between idle and engine decel overlap and idle will have to take priority.
So that's what I've done thus far. It's a long read, but maybe some of my experiences will help you in yours. Expect updates as I continue tuning throughout the summer.