ozzimark

I've had to dig three of my neighbors out of the parking lot so far, one of whom slid sideways into my bumper trying to get out. Unfortunately, no damage, so no R bumper yet :lol:

The front passenger seat folds forward. There are two little black catches that you have to lift to release it.

Thank you for that, for your straight-forwardness, I present to you: :pizza: But know that I'm still gonna test it when I get the chance. This brings up an interesting thing though. The ECU relies on airflow to monitor boost. If you end up increasing pressure enough that the airflow limit on the MAF is exceeded like you are doing, how does the ECU monitor and control boost? Perhaps it's for the best that you are not using the ECU for boost control ;)

Exactly. When so little is known about the fundamental operation of these ECUs, why leave it to shouldn't, when we have the ability to find out what the actual effect is? Maybe my philosophy of finding out as much as I can about a system will get me into trouble someday, but this type of response is the plague of the Volvo performance community imo. I don't mean to offend, but you created this functionality in the ECUs, and gave us the ability to mess with it, and yet you're suppressing the quest for additional knowledge and understanding of the tool you have created by simply saying that it "shouldn't" do anything besides induce fuel cut. :blink: I'm still in favor of adjusting the sliders, just not so much that the ECU hits fuel cut. If you don't wanna do it, I'll just find out on my own later :lol:

That's exactly it I figure it takes 5 minutes. Log a run, change the sliders a bunch, log another run, look for any obvious changes in what the ECU is trying to do. B)

Hm. does the ECU behave differently if you have it set otherwise?

Fascinating. I'll keep that in mind for when I change my O2s.. If I didn't live on the opposite side of the state, I'd offer to help you out with monitoring data during pulls Adam needs to get the built-in data logging in TT sorted out asap, it's pretty much the only thing that's holding me back from getting one at this point. Also, you haven't messed with the boost control within TT at all because you're running a standalone EBC? Have you considered switching back to ECU control? From some things that I've read on teh intarwebz, it seems that the ECU may do funky things with fuel and timing when it can't quite get the boost levels it is aiming for. Who knows if that's actually true though :blink:

Wow, looking pretty good H! How much smoother is the engine when pulling in high gear? I'm glad to see that the timing is coming up as well. Sounds like it's time for you to get back into that Quaife group buy. ;)

Yeah, you definitely seem to be on your way towards resolving the issue, I'm just concerned that both your custom TT tune and the Woth tune have the same richness issues combined with what looks to be timing pull. I'm picking my brain over possible underlying issues that would cause that behavior in your logging, or if it's really just a tune problem. Did you try unplugging the knock sensors from the wire harness as was suggested?

I don't actually, I was just curious. You're definitely not running out of fuel, that's for sure, but it occurred to me that the opposite could be happening, and FP is higher than expected, causing the strange richness. The ignition timing is also still slightly retarded from what would be expected. Have you messed around with cam timing recently to see how it affects the rich area?

I'm convinced that this is more than just a tune issue. How close to stock is your fuel pressure?

Huh. Interesting routing on the air intake and clocking on the compressor housing on that 4cyl edit: are there larger versions of the engine pics? I didn't see them with a cursory glance at volvo's website.

Both are explained in the pics themselves Green is how much fuel the ECU should be injecting at various RPM and load points, I'm assuming a duty cycle ranging from 0 to 250, where 250 is fully open all the time. Blue is timing, in degrees BTDC

Or try simply re-torquing the bolts that hold the knock sensors in. That might be a tight squeeze with the manifold on though :lol:

It would be nice to know how the ECU calculates the engine load... and what it considers to be that "full throttle" tripping point. I believe he is not stating that 15psi is different at 1/3rd throttle and WOT, but that the ECU interpolates different load cells for the two different conditions.

It's not the electrical wiring that would be the hard part. It's the software in the ECU. Changing tables for fuel and timing maps is one thing. Changing the way the ECU interprets inputs to read those maps is entirely different.

I suspect very difficult, since the basics of how the ECU controls ignition and fuel has changed Also, from the get-go, my impression is that TT's main super awesome feature is that you can just drop it in without having to make significant changes for it, such as doing custom wiring for a MAP sensor or COP outputs. Doing these things would be awesome, and I'm all for it, but it seems to me that they are outside of the scope of the product. It's also not too far from just moving to a complete standalone system at that point. Jan, even if you do have all those cells in the middle, if the ECU can't distinguish the difference between 15 and 20 psi in airflow, you end up with a big dead zone in boost where it's gonna run pretty rich if you're not quite at target boost. I was having this discussion with Eric yesterday, and he assured me I was just being too anal about it, and it's a non-issue. To an extent, that is true, because there are plenty of high powered cars out there that run just fine on the motronic system. However, it just strikes me as being a solution that is far less than optimal if you really want to have good control over what the ECU is doing with the engine. Perhaps there is a way to remove the ECU imposed limit on the MAF sensor signal. That would solve a lot of the problems I am having with airflow measurement :ph34r:

I don't disagree at all, but I find it curious that even though in theory, the 3" MAF doesn't improve flow limitations by that much, Jan still went through the effort of scaling all of the load cells for the larger housing, while possibly not seeing the actual benefits of being able to accurately measure airflow at 400hp. As such, I assume that there is something I am overlooking in the behavior of the MAF sensor.

Though even if you move up to a 3" MAF housing, that's only a 20% increase in flow area.. so if Hussein's limit of 231 g/s is the actual limit for all M4.4 ECUs, that only brings us up to ~280 g/s, which still isn't enough to give satisfactory flow headroom. I know Jan will read this as some point. Jan, on your setup, have you kept track of how much air flow the ECU reports going through the MAF? I know you've said that you don't hit 100% load, and you're closer to 50% by the time the rev limit rolls around, which implies that there is some other factor at work here that I'm mindlessly overlooking :blink:

I'm not expecting it to be. I also suspect that something simple like removing the knock sensor bolts and properly torquing them might eliminate the issue, if it actually exists

But if the ECU is reading engine vibration as knock, it will pull the timing, even if there isn't actually knock, which was his point. Thus why adjustability of the knock sensor sensitivity would be nice. :)

Sounds like tonight is a good night for a 1am drive. I woke up this morning to a few inches of unplowed snow on my way to work. I love being behind pickup trucks that don't think snow tires are a good idea, and then getting a windscreen full of snow flung at me as they pull away from a light or stop :rolleyes:

I don't think he has a choice in the matter unless he switches to a larger MAF housing and does a lot of work scaling the tables around. I've seen around 215 grams/sec on a 100% stock setup, so it doesn't seem that Volvo gave us a lot of headroom to work with if 231 g/s really is the max <_<

Magic gas goes bang and the car goes vroom. Plain and simple, the right amount of overlap is good. Too much is bad, too little isn't as bad, but isn't optimal. Too much WILL result in reversion. How much is too much? As Lucky took the time to explain, it depends on your own setup, tune and operating conditions. You say that exhaust is being forced out? It seems to me that you're treating the exhaust as an incompressible fluid. Flow depends on pressure differential across the valve, not the cylinder motion. If the intake valve opens while there is more pressure inside the cylinder than in the intake port regardless of N/A, turbo or supercharger, guess what happens? :lol:

I get 83.4%. The TPS has a wider range of motion than the throttle plate does as far as I can tell, thus why it never hits 100%. I'm also pretty sure the ECU knows this and scales the input accordingly based on the min and max values it sees.