So what's your process starting out? Do you get a map that idles and revs decent with no load and go from there adding and subtracting fuel while driving? I'm just talking about baseline stuff.wondering if we're on the right track.
CK5
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76 K5: Megasquirt EFI, Electric Fan, and ICON Coilovers
- Thread starter secutright
- Start date
Ah, I happen to have screen shots of all my settings on this PC. Here's my AE setup. I gave up on X-Tau because it always ended up giving me pulsewidths of 0 on decel. With your wet manifold, you should try to make X-tau work, but save that for after your VE is finished.
I like to set it to 100% MAPdot and play with those settings until lean tip-in is minimized. Then do the same at 100% TPSdot. Once both work as well as they can on their own, find the blend that gives the overall flattest AFR. So on small transient events, AFR should be flat. On big throttle stabs it should go rich. That's why it's progressive.
No, AE won't mess up your VE tune. For tuning you will use slow throttle changes anyway and try to hold the engine "in each cell" for several seconds at a time. Only during steady state can the O2 lock in a good number and the autotune make corrections.
I like to set it to 100% MAPdot and play with those settings until lean tip-in is minimized. Then do the same at 100% TPSdot. Once both work as well as they can on their own, find the blend that gives the overall flattest AFR. So on small transient events, AFR should be flat. On big throttle stabs it should go rich. That's why it's progressive.
No, AE won't mess up your VE tune. For tuning you will use slow throttle changes anyway and try to hold the engine "in each cell" for several seconds at a time. Only during steady state can the O2 lock in a good number and the autotune make corrections.
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Here's my AFR and VE tables. I run dual O2 and fuel the left and right bank separately, but the tables are nearly the same. You can see that my TPI pulls hard in the midrange. Your peak VE numbers will be at higher RPM because of the cam and intake. You can see that I idle just under 14:1 and have a sort of lean cruise setup.
Here's my timing - see how the lowest bin has higher timing. This pushes the engine towards the desired idle speed.
Here's my timing - see how the lowest bin has higher timing. This pushes the engine towards the desired idle speed.
Have you read the tuning section of the megamanual? The hardest parts are usually getting it to actually start and keep running, then getting the transients and cold enrichments right. You want a starting table somewhere in the ballpark (i.e. from a similar engine), but once it runs and you get O2 readings you can let it tune itself. Start with low loads and low speeds and slowly increase both. It will keep adding to cells as you get close to them.
Team208Motorsports
Its Magic Bitch
I think you have a basic grasp on tuning but there are problems in the maps you just put up. Especially for a street driven rig.
The idle area of you VE is too coarse, you can't rely on interpolation to control idle. High timing won't push the engine towards idle, it'll actually keep the engine idled higher. Does it take it a few seconds to return to idle? Like it hunts a little. If the timing and VE table are truly set properly you can just use them to control idle, as in turn off any advanced idle control.
I'm not critiquing here, just an observation with the data that was given. MS is one of those systems that has subsystems which can take up the slack from coarse tuning.... A lot of newer aftermarket is that way as well.
The idle area of you VE is too coarse, you can't rely on interpolation to control idle. High timing won't push the engine towards idle, it'll actually keep the engine idled higher. Does it take it a few seconds to return to idle? Like it hunts a little. If the timing and VE table are truly set properly you can just use them to control idle, as in turn off any advanced idle control.
I'm not critiquing here, just an observation with the data that was given. MS is one of those systems that has subsystems which can take up the slack from coarse tuning.... A lot of newer aftermarket is that way as well.
Pretty sure that fits the definition of critiquing...
Those tables are 10 years old, it's just all I have on me. Perhaps I shouldn't have posted them. I wasn't planning on him copying them, just an idea of what somebody else had set up with a SBC. I have revised the idle areas since then (I think I changed the RPM bins, too IIRC) because it wasn't entirely consistent. I actually use closed loop mixture for idle now. There are provisions for closed loop idle speed with the IAC motor, but it works well enough I've left it set up only for warm-up.
But we're not tuning my truck...
Those tables are 10 years old, it's just all I have on me. Perhaps I shouldn't have posted them. I wasn't planning on him copying them, just an idea of what somebody else had set up with a SBC. I have revised the idle areas since then (I think I changed the RPM bins, too IIRC) because it wasn't entirely consistent. I actually use closed loop mixture for idle now. There are provisions for closed loop idle speed with the IAC motor, but it works well enough I've left it set up only for warm-up.
But we're not tuning my truck...
Interesting, DIYAutoTune actually recommends setting the lowest bin below your idle a tad higher like @Blue85 suggested, which is how I set mine up. I have read the tuning portion of the megamanual, feels pretty vague to me. I'll go read over it again right now. I feel like we've got the idle mixture down, I'll probably try to lean it out again just to see what happens. I'm hoping to get to play around with it some more this weekend, so I'll get that AE in place, I was doing some reading on how to tune that. I didn't think about it for gradual tip in. I was thinking more along the lines of a carbed accel pump, where it only squirts when you stab the throttle. I could see where that could be messing with the area in concerned about, since it's running to those guns with no AE, it's already starting off lean, then takes a while to recover, by which time the engine has already sped up more and has moved on to another bin...
I'm not looking to copy anyone's map and just run it, but having a baseline to compare to is very useful, and I've had a hell of a time finding maps for anything but Miatas...
Goodwrench 350 (stock cam) with TPI on top and Ford EDIS ignition.
I think I used a VE table from a TPI Camaro as a starting point.
If you look at the AE settings, there are thresholds - below those levels no AE happens. So it's up to you when you want it coming in.
I think I used a VE table from a TPI Camaro as a starting point.
If you look at the AE settings, there are thresholds - below those levels no AE happens. So it's up to you when you want it coming in.
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Any updates?
Wow, it's been a little while....
Been busy building other people's trucks lately. Fuel injection is pretty close, enough for me to run it anyways... Front suspension is awesome, rear is still awesomely awful.
On that note, the rear end of it is currently being developed. I have most of the parts, just waiting for the time between our company projects. Probably be installing it between the end of July and beginning of August. If all goes well it should be pulling some good numbers. I'll put some pictures up of the progress when it starts to happen...
Mostly been enjoying driving it in the meantime, taking trips with the family to go "treasure hunting," what the kids refer to Geo caching as.
Oh, reading back through the last couple posts, I did find that it ran much better when I took some steps out of my IAC, and used the idle screw to put the air in instead. I remember seeing somewhere that helps with the initial tip in, since the blades are already cracked open a tad, it doesn't get as much of an inrush of air when your crack the throttle.
Hope I moved the right direction with that, made a huge difference in the coughing off idle...
Hope I moved the right direction with that, made a huge difference in the coughing off idle...
Stumbling off idle is usually lean. Look at the VE bins at idle and where it moves right as you tip in. You probably won't be there long enough to get good O2 readings, but try richening those cells a little at a time and it will probably help. I fixed my tip in problem entirely that way. If you try to get it with AE, you'll have to crank the mapdot settings enough that's it's triggering all the time.
Oh yeah, I do the same thing - I set the base idle with the screw and basically only use IAC for warm up. I thought it would be unstable without closed-loop idle speed control, but it seems more stable this way, vs. having the IAC keep moving. I always thought I would go back and set it up on closed-loop idle control, but there really hasn't been any reason to.
Oh yeah, I do the same thing - I set the base idle with the screw and basically only use IAC for warm up. I thought it would be unstable without closed-loop idle speed control, but it seems more stable this way, vs. having the IAC keep moving. I always thought I would go back and set it up on closed-loop idle control, but there really hasn't been any reason to.
OMG thank you!
Double triangulated rear links is now in process. The single triangulated wasn’t cuttin it.
Here’s the 5 day thrash we did to build the rear. Yea 5 days.. we actually had the links on in once night with the brackets racked up. Only because @secutright does so much preplanning, unfortunately that can only take you so far so the rest of the time was making hoops and the mezz stuff fit.
And yes it works, no we didn’t get video, and yes it has 23 inches of usable working travel, with a 2.5 coilover and 3.0 bypass along with the 2 in bump stop.
Here’s the 5 day thrash we did to build the rear. Yea 5 days.. we actually had the links on in once night with the brackets racked up. Only because @secutright does so much preplanning, unfortunately that can only take you so far so the rest of the time was making hoops and the mezz stuff fit.
And yes it works, no we didn’t get video, and yes it has 23 inches of usable working travel, with a 2.5 coilover and 3.0 bypass along with the 2 in bump stop.
Here’s a couple more pics from building it and I actually don’t know why we keep trying to do the impossible.. really hurts a few days after it..
Why the big arms out the back?
Martin
Martin
So you're able to mount the hoops and shocks at the rear of the truck (which could allow for a back seat) and you're getting a greater total travel than the coilover itself offers. What about the non-linear movement of the coilover vs the axle? Won't that be difficult to tune? Is it stable at speed to have the weight of the truck supported 2 links away from the axle? How is the frame reinforced for this?
This truck kicks ass! 
