Positively Displaced

[tooquick260]

Great,, How does it feel? Did you get on it at all. 

[Xnke]

Feels terrible. I may have been able to get control of the spark map, I'll know if it worked after work today. No plenum installed, so I am pretty much just running long-runner ITB's right now.

[Xnke]

Made the switch to MS2-extra; and am tuning the alpha-n table right now. Car feels great from idle to about 3500 so far; as long as you are accellerating. On a cruise throttle, the car wants to go seriously lean and jerks and misfires pretty bad. Autotune wasn't even CLOSE to being able to correct this, so some gross tuning adjustments and we'll see how it goes.

[Xnke]

Ok, no improvement at ALL on this front. The car is undrivable. At this rate, I will never get it running correctly. An LS1 is really looking good right now.

 

I'm getting ignition hiccups at idle, and while driving the car bucks SO HARD I'm afraid of snapping an input shaft. Yes, It's that bad. My face has hit the steering wheel a few times.

 

Nothing at all should be causing this. There is nothing special here compared to any other ITB intake, I'm not running any boost, there is NOTHING at all wrong, mechanically. I can't find any noise electrically, but the MS resets and I hear a fuel pump relay clicking, or the RPM burps, or I get another bloodied nose from the car pitching me into the dash again. Alpha-N tuning in megasquirt REALLY sucks. There are apparently NO tools for it, everything is completely setup for MAP only setups, and even the logging tools in tunerstudio don't seem to be able to do it. I've followed all the instructions I can find anywhere on any website for any engine in any car and can't find any rhyme or reason to it.

[tooquick260]

Somebody has to have some infor for this. Sorry you are have these issues. Take a step back and clear your head. You can figure it out.

[Tony D]

Tuning acceleration has always been the easiest part.

Start rich, work lean, disable all fuelling tweaks and warmup enrichments and work on a warmed up engine first to get a good map.

Auto tune does not work unless you are already close, but never depend on it to do the work you should be doing.

 

Hold load points, lean till you buck, go back rich five clicks and move to the next load cell. You should be able to get close ping that with a long gradual hill and no other instrumentation.

 

If you are belching fire out to ITB's consider you have too much spark advance and are early-firing the next cylinder in the firing order, or previous one! Or are lean.

 

Leading us back to richer it up, go from rich to lean...

 

This isn't endemic to MS, it's the same for all EMS

Edited May 4, 2013 by Tony D

[bradyzq]

Also, when using Autotune, it is slow to change the mapping. I've found that it's better to uncheck "update controller" and simply log while driving slowly through as many cells as you can, then update the controller manually.

 

If you're getting resets, try using the noise filter on the crank trigger input. You should be able to see the trigger waveforms in Tunerstudio, and will get hints as to what the noise is. Do you know what the reset/sync reason is? You can log that.

[Tony D]

One thing experienced tuners do on the dyno is HOLD THE LOAD POINT... Let the tuning take effect and see what it does.

It takes about 45 minutes to do most of the driving map with a WBO2 in the collector. It takes two to three times that long if its a sniffer in the tailpipe!

 

You have to see what your lag is from a change to where it shows on the wbo2 as a STABLE reading... Then you know how long you need to stay in the load cel before making an adjustment

[bradyzq]

Not that you were necessarily referring to my "slow" comment, but in case you were, and to clarify in general, with the MS2 autotune, you can choose to have the ECU update the fuel map automatically, but it will do it in small steps. Or, you can get only WBO2 readings in all cells, with no live changes to the fuel map, then after ask the ECU to calculate the full change needed in each cell. This can be done in either Tunerstudio, or with VE analyze in Megalog Viewer.

[Xnke]

Well, I found the big problem...there is a bug in MS2/extra v3.2.4 that really makes TpsDot flip it's wig. This, in turn, causes the accel enrichment to trigger when it shouldnt, and sends the engine into such a rich mix that it stalls...the rpms drop, accel enrichment drops, engine catches, revs up, accel kicks in, ect.

 

Moving to the 3.3Alpha5_gslender_v2.8 modified code changes the TPSdot system to a moving anchor type setup, backported from MS3. This cured the issue, and now I'm just tuning two tables; the Alpha-N table has to be done by hand, but the speed-density side of things is being handled pretty easy by the autotuner. It takes some time to get the tuner setup, but once it is, it handles things OK. It's not perfect, but it gets me close enough to make the adjustments by hand. It cruises a little rough, accel is ok, low-rpm, low load is crappy and I'm still working on it. The constant rain is KILLING me...I can't get on it much at all without blowing a tire off. Yes, I'm still running an open R200 diff...the OBX helical is on the list to obtain this year.

 

All of this may go out the window if I can get my ford MAF installed...I have a nicely calibrated curve for it and it will handle the HP with plenty of headroom. I will have to do only minor tweaking to the correction table, but it seems to be the universally preferred method for boosted ITB's in factory installations. With MS2-extra, if you have a good calibration curve it's a plug-and-drive tune. Directly metering the air coming in, plus directly metering the fuel going in, makes for very little tuning to be done...set your AFR tables and the computer is already doing the math.

 

Just have to figure out how to get the behemouth installed! I have a Nissan N60 MAF too, which would be easier to install between the intercooler and the manifold...but I don't have a good calibration curve for it. The ford MAF would have to go pre-super, and I'm not sure what kind of compensation I'd have to do to make up for the temperature change from the intercooler.

 

It's a Ford Taurus SHO V8 MAF, good for as much as 400HP. It's also the unit installed on the Ford Lightning pickup. In the lightning, it's installed as a draw-through meter right infront of an Eaton M112, so I know it can handle that type of service. The only issue I have is room! This thing is just BIG. 80mm diameter; Ford F50F-12B597-AA AF80H-01A.

 

Even if I don't use it for fueling, having a calibrated mass air meter would allow for ballpark HP estimates based on real airflow numbers, so it's a decent tuning aid. More air being consumed = more horsepower out, generally.

[Xnke]

As far as being lean and snapping out the throttles, I've got most of that cured. The timing curve is the same one I ran on this motor with the old intake; and it's only a lean snap occassionally right now. Putting your foot into the throttle sends the motor dead rich at this point; but even dead rich it is getting squirrly on the constantly wet pavement.

 

Lots of tuning to do. It's getting better, once I figured out the TPSdot issue I wasn't so upset with the work/result curve. I will be driving the car to work in the morning.

 

I did get the hood cut out and the cut edges painted this afternoon, and I'm rocking the UPS hood vent right now. (cardboard box taped onto the hood.) It's only there to keep moisture off the paint till it cures up.

[Xnke]

As far as the actual tuning goes, the speed-density part of the map is going well. The alpha-N portion just doesn't have very good tools yet, and it's slow going. I've been trying to get a few hours of tuning done at a time, a little every day, and mixing in some mechanical work to keep my mind from going berserk on this. Hopefully I'll have some good shots of the hood bubble tomarrow.

[Tony D]

Ford Lightning MAF... Argh! Someone is making an offset box for it because he's running off its calibrated tables already!

 

Like you said, the airflow allows pretty easy correlation of dyno readout to Theoretical HP being produced... But the overhead everyone thought was there really wasn't... Not in turbo form above 7,000 at least! ;^p

[Xnke]

It'll do close to 350 grams/second of airflow, which I won't exceed with this supercharger. I would be very close to maxing out the N60 Nissan MAF, but it would fit so much better...argh.

 

I am going to be hunting down a 4" cone air filter and a piece of 3"-ish hose to clamp the MAF to the inlet of the super, and I'll give it a go tomarrow. Should pull about 4.5g/second of air at 1100RPM Idle, which I can datalog (after modifying the logger! Why does everyone always just assume I'll use speed-density!?!) to make sure I have the calibration curve correct, and If it's correct I'll flip the maps up and see if I can get it to drive politely on the MAF...it would be so bitchin' if it works...HUGE amount of time saved.

 

The list of "finish this NOW!" is below:

 

Make the car run and drive acceptably

 

Make the car run and drive under boost

 

Exchange transmisison and shorten driveshaft

 

Put the studs into the hood vent. Finished up with 3 layers of 6.5oz cloth, 2 layers of chopmat, and 3 layers of 6.5oz cloth.

 

Bolt the hood vent onto the already-holed hood. (did it this afternoon, It isn't so bad. I could probably just leave a hole in it if I *had* to, but I don't have to and I've already got the vent ready to bond studs into to bolt it down.

 

Proper MAF sizing (this one is just a little too big, but i can deal with it) means better drivability; which is going to be the hard thing to get with blended tables and ITB's with MS2-extra. Going for max power, the blended table system should be fine...but the MAF setup should give me better in-town manners for far less effort, so I hope it works out for me. If it doesn't, well I've driven a rowdy car for a bit, I can deal with it for a little longer.

[bradyzq]

You can also try ITB mode instead of blending manually. This results in only one load axis that autotune understands.

[Xnke]

ITB mode absolutely will NOT currently work with a boosted motor. It has no idea how to handle a MAP signal over 100kpa; and the developers are not concerned with it right now...too many other things on the table. It wouldn't be too hard to get it to deal with the MAP signal properly, but as it sits now...ITB mode doesn't do boost.

 

(wish I'd known that when I started!)

 

Anyway, the MAF sensor will be mounted in the car this evening, and I'll have to work out an air filter mount. It is supposed to rain every day for the next month...just about. There are two days with a rain chance of less than 50%, so hopefully I'll get the transmission installed on those days.

[bradyzq]

Hmm, hadn't thought about boost being an issue. Sorry! I guess you are in the unlucky minority. Been there.....

 

MAF is definitely a good solution, but trickery _might_ work too.

 

There may be a hole in this idea that you could drive a truck through, but at the moment I can't think of it:

 

Turn off, or adjust according to the "new" MAP sensor output, any baro compensation, then tell ECU you're running a 1 bar MAP sensor. ITB mode should then work. It's kind of a weird load scale anyways, so it might not be too hard to deal with. The only issue I can think of is that the switchpoint is not adjustable in MS2, just MS3. So, I'm not sure if the Alpha-N portion would ever activate.....

[Xnke]

Yeah, it's adjustable in the newest alpha code versions...and you don't want to tell it that it's a 1 bar. If you do, it won't run at all...different voltage ranges. I *DID* get it to run a little on ITB mode N/A, and it was much smoother...but...

 

This car is a total animal under boost. I hooked the MAF up with no filter on it this evening, it's just floating there on the inlet to the super. Slapped the needs-work belt tensioner on there and snugged up the belt, hooked up the pneumatic bypass controls, and fired it up on MAF-only fueling, with a speed-density spark map. Never made it over 2500RPM and it's already AWESOME.

 

Having a very good MAF curve is essential! So far, I have done ZERO adjustment to the MAF curve, and have carefully edited my AFR target table to put me at about 12.5:1 under boost, and 13.8 when out of boost for now. I'll adjust the fueling later, once I have the MAF curve fully proven. (I'll probably do most of the fueling adjustments on the dyno in late June/early July.

 

This is TOTALLY the way to go, if the engine is well suited to MAF operation and a good quality unit can be obtained with appropriate flow ratings. It really is a plug-and-drive operation, if you have a good curve!

 

Tonight, I'll be finishing up all the minor vacuum leaks (thus the tuning for rich operation right now...vacuum leaks will cause a lean condition under vacuum and a rich condition under boost) and figuring out an air filter. I would love to get a filter box made and installed so I can duct cool air to the filter, but I need a filter to go on there first! The belt will come off and the tensioner adjustments will be made, then I'll be reassembling the tensioner and hoping my belt tracking problem will be fixed.

[Tony D]

Watch for stray air currents...shield your MAF well, like with a long inlet tube.

JeffP ran into an issue while moving that threw the MAF off compared to running and tuning on a dyno!

 

Having it sit perpendicular to vehicle direction with at least 4 diameters of straight tubing before the filter does orders for consistency of flw numbers, stationary or in motion!

[Xnke]

I don't have any real room to put a lot of tubing between the maf and the filter...but the filter will be going into an airbox. The MAF was bolted directly to the airbox in the original application, so I figure if that worked for a production car (most all production cars) then I could do worse than to emulate them.

 

More composite work will be needed to get an airbox built, but now that i am not spending three weeks on street tuning, I have a little time to get that done.

 

I think I'll have to pull cool air from a fenderwell...any real downsides to that? It's a low pressure, moderate turbulance area, with potential for debris, but the other option is go straight down and pull air from beside the starter.

Edited May 8, 2013 by Xnke