Practical Standalone Tuning: Step 3: Base Table Configuration

Back to course

Watch This Course

$229 USD $91.60 USD

-OR-

Or 8 easy payments of only $11.45 USD Instant access. Easy checkout. No fees. Learn more

Enroll Now
8 easy payments of only $11.45 USD

Course Access for Life

60 day money back guarantee

Step 3: Base Table Configuration

20.15

00:00	Now, we can move on to our base table configuration step.
00:03	And the idea with this step is essentially just to get some broad numbers into some of our key tables that are going to be close enough to at least get us up and running and get us started.
00:13	They do not need to be perfect and we can easily come back and make adjustments as we see fit to these tables as we go.
00:20	So, it's just enough to get numbers in here to get the engine up and running.
00:25	The key tables we're going to be looking at here are our fuel table, or more correctly our VE table.
00:31	That works in conjunction with our air fuel ratio or lambda target table.
00:35	So, we'll also be addressing that.
00:37	Of course, we're going to be addressing our ignition table and then we'll look at a couple of our engine protection tables, namely our boost cut or manifold pressure limit and our engine RPM limit table.
00:49	So, let's start with our fuel table.
00:51	Alright, so looking at the fuel table, we've already got numbers in this, it's already essentially set up from a base file.
00:56	So, do we need to make any changes? Well, yes we probably do.
01:00	What we want to do is have a look for a start at the setup for our load and RPM.
01:05	And our load at the moment you can see is set to manifold gauge pressure or MGP in link spec which is essentially the difference between our barometric pressure and manifold absolute pressure.
01:18	This is a personal preference really and what I'm going to do is go through and adjust that to manifold absolute pressure which would be more typical.
01:27	Of course, we've got engine RPM on our horizontal axis which is also normal.
01:33	So, what we can do here is press the X key which will bring up our axis setup box.
01:38	If we don't remember the hot key though, we can always go with our right press of our mouse and axis setup is right at the top.
01:45	So, let's change manifold gauge pressure to manifold absolute pressure.
01:49	So, all we need to do is type in MAP and it will fill itself out there and we can click on initialise axis.
01:56	Now, by initialising this axis we can just scroll through here and have a look and we can see that it's put breakpoints essentially every 20 kPa in there.
02:05	And it's spanned out to 240 kPa.
02:09	This is 240 kPa absolute so 140 kPa of positive pressure.
02:17	That's probably actually about right, that's about the peak number that I'd expect to run but let's just add another breakpoint here at 260 kPa.
02:26	So, 20 or even 25 kPa, absolutely fine, we may want to come back and add a little bit more resolution around our idle and cruise areas, but we can do that at a later point.
02:36	Let's have a look at our engine RPM and our breakpoints here look pretty good.
02:40	Generally, I recommend 500 RPM breakpoints.
02:42	We can see that we've got a couple of extra ones in here, 750 and 850 RPM.
02:48	Arguably at this stage not necessary, but it can be beneficial to have a little bit of additional resolution around the idle areas.
02:55	We've also got one in here, 4750 RPM, probably at this stage that one not necessary, so I can use the little X and remove that.
03:04	Basically, I don't want to make more work for myself than I absolutely need.
03:09	We've got the RPM spanning out to 8000 RPM and I'm going to be rev limiting here at 7500 so pretty normal just to span out a little bit beyond the normal RPM range that I'm going to be expecting.
03:23	So, I'll click OK and we can see that's shrunk our table quite nicely.
03:27	So, just again just discussing gauge versus absolute pressure units, now it's really important to understand which we are using.
03:36	And we can see here that at the moment with the engine not running, we've got this little yellow box that shows us where we're currently accessing which is the 100 kPa site.
03:44	So, 100 kPa, this is essentially our atmospheric pressure.
03:47	So, one bar of positive boost is going to be our 200 kPa row.
03:52	And as I mentioned, 240 kPa, about our maximum, just span a little bit beyond that.
03:58	Alright, numbers for this table and with a VE fuel model, as you've already learned from the body of the course, generally I'm just going to start by setting the entire table by clicking the box in the top left to a value of 50.
04:10	Don't need to worry any more about that, we can again come back and start adjusting this as we see fit when we get the engine up and running, but this should be now enough if we've got our fuel configuration set up and our injector characterisation about right, should be enough to get us up and running.
04:27	So, that's our first key table addressed there.
04:31	Let's now head across to our air fuel ratio target table.
04:36	So, we'll just access that by using our search box and entering AFR.
04:41	So, we really wanna make sure here that the break points and load axis just sort of make sense and match.
04:48	We can see that we are already using manifold absolute pressure here.
04:52	The key one to watch out for is if this ends up accidentally configured with throttle position as the load axis, that's not going to work on a boosted application.
05:02	So, we wanna make sure that that is correct for our application.
05:06	We don't need to be as granular here with our break points either.
05:10	You can see this is a much smaller table.
05:13	So, the numbers that we're gonna put into this, well let's understand what we're looking at here.
05:17	So, we can see already by default this table, most of it here in the cruise area is set to lambda one which is obviously good for fuel economy.
05:27	Probably a little bit premature here at 90 kPa, going as rich as 0.95.
05:32	Generally, I'll make that change at around about the atmospheric pressure.
05:36	I mean these are also not set in stone and we can make whatever changes we personally prefer.
05:43	To make my life a little bit easier here we can just use our shift key and our arrow keys to highlight those three rows and then if we right click here and we come back to interpolate and we use interpolate vertical or of course shift plus V, that'll just interpolate those numbers nicely for us.
06:03	Now, what I'm gonna do here, add a positive boost pressure of 100 kPa, so 200 kPa absolute, 100 kPa gauge.
06:12	I'm gonna set the target there to 0.80, reasonably conservative there and again I'm just gonna highlight up to that 100 kPa and shift plus V and that's going to fill that in.
06:25	And then what we can do is come down above 200 kPa, I'm gonna target 0.78 lambda and we really shouldn't be getting anywhere near 300 kPa, so that's gonna be absolutely fine.
06:39	Again just to reiterate, we can always make changes to these lambda targets, the idea here is just to get some conservative safe lambda targets that we know we don't necessarily worry about right from the immediate first start.
06:52	Now, one thing I will mention here is that at higher RPM, sort of 4000, up to 8000 RPM, in vacuum, so no load there.
07:02	You can see I've got those set to lambda one at the moment, nothing necessarily wrong with that but for a car that's going to be pushed hard, particularly a competition car, maybe one that's going to be also road driven, it can be beneficial to set those lambda targets at higher RPM, but low load, a little bit richer, maybe 0 .95 for example.
07:22	That's just going to add a little bit of additional fuel to help cool and control our combustion charge temperature on overrun.
07:29	This obviously only works if we've got our deceleration fuel cut off disabled, so that we're not switching the injectors off, but that's something I'll quite often do on cars that I know are going to be driven hard.
07:39	Doesn't really affect our fuel economy dramatically because when we are actually genuinely cruising, it'd be unlikely that we'd be much above about 3500 RPM, so it can just be a little bit sensible in the areas that we choose to change.
07:53	OK, so now we've addressed our fuel table or VE table and our AFR target table.
07:59	Let's press the i key and we'll come across to our ignition table and have a look at this.
08:04	I should have also mentioned here by default the way the link tables are set up is the load goes from the top to the bottom, from low to high, so as I move down this table we're actually increasing boost pressure or load.
08:18	Somewhat counter intuitive in my personal ideas, but each to their own.
08:24	It doesn't take too long to get your head around it and you can swap this if you really prefer but by default this is how the link maps work.
08:32	So, again looking at our breakpoints here on our load for manifold absolute pressure, it is already mapped, so I'm not going to need to change that.
08:41	We've got breakpoints about every 20 kPa.
08:43	We could go a little bit broader here, engine's not as sensitive to ignition timing as it is to fuelling, but I'm quite happy with that.
08:52	And again looking at our breakpoints on our RPM table, we're pretty much exactly what I'd normally, run with the exception we've got a couple again down in the idle area, so I'm happy to leave those there.
09:04	So, what we want to do is just get some numbers into the table here that are going to be pretty conservative while we get up and running.
09:12	So, what I'm going to do is highlight here out to 100 kPa and we're going to start by setting this all to 15°.
09:20	Now, this is what I've done through the majority of the worked examples and I know how conservative this is, we've had a few comments about this and really I'm just trying to teach a method that is absolutely as safe as it possibly can be.
09:34	But if you're a little bit more competent with the tuning and maybe you've done a couple of engines already, what we can do in the lighter load areas again is we can just step this up a little bit.
09:44	So, now I know in this region I'm probably more likely to be in the range of 35 to 40° so 25 is still very conservative, this is coming from my own experience, but I understand if you're getting started, you don't have that experience.
09:59	Stick to 15, it's OK, it's just going to give you a little bit more work to do when it comes to optimising the ignition timing.
10:06	Alright, so now what we want to do is look at our positive areas of boost.
10:11	We do need to be mindful with the 4G63, particularly on a lower grade of pump fuel than the 100 plus that we're running, they can be very knock sensitive, particularly around peak torque, so they're 3500 to 4500 RPM, so we do want to be a little bit mindful of that.
10:27	So, what I'm going to do here is just set our entire table to 10° at the moment, and then we're going to make a few changes here.
10:36	So, what I'm going to do is above 5000 RPM, we'll ramp that up to 12°, and what we'll also do is around that 4000 RPM and down to let's say 180 kPa here, what I'm going to do is pull that down to 5°.
10:54	Now, this still may turn out to be a little aggressive in some places and that's fine, remember we are going to be using audio knock detection, so if I hear any knock, I can just stop, address the timing and make the appropriate changes.
11:06	Now, just because I am a little bit fussy here, we've got a big step here, 25 down to 15° so what I'm going to do is just hand smooth that, we can either use the interpolate function or in this case I'm just going to do it by entering the values.
11:20	Now, I just did also notice there I missed out, we've got a couple of additional breakpoints in here in our load that I don't necessarily think we need and again I'm all about making my life easy where I can so 170 kPa, I'm just going to take that one out, and 190 kPa, we'll take that one out there and we will press yes to interpolate, that's going to mean that essentially we've made no changes to the table itself.
11:44	Again we can always come back and add in additional breakpoints if we really feel we need it, but generally it's very unusual that you'd need or want to do that on the ignition table.
11:55	So, at this point our ignition table is set up and we're comfortable, that's going to be a pretty good safe place to get ourselves started.
12:02	Let's press the escape key and what we're going to do is to have a look at a couple of other tables and actually we'll start by having a look at our fuel corrections.
12:12	And what we want to do is look at our cold start and specifically here our warm up enrichment.
12:18	Now, this shouldn't be a problem, but it is something that we want to be mindful of and actually, straight away I can see there's a potential area here where we could maybe end up with an issue.
12:30	I've had this a couple of times in the past where I haven't actually made a point of looking at the warm up enrichment table and I've found that I'm having trouble getting consistency in my fuelling.
12:41	And when I've looked back at the warm up correction table, I've found that in the area that I'm actually running in, there are corrections.
12:48	So, typically we'd expect this engine to be running between around about 75 and 85 degrees when it's up to normal operating temperature.
12:56	And you can see that this axis here is related to throttle position, not manifold pressure.
13:03	So, if we're at very light throttle here, we can see that we actually could potentially be dropping into that 70 degree cell and adding warm up enrichment.
13:12	So, what I want to do is just make sure that when the engine is truly warm, that I am not going to be getting any warm up enrichment.
13:20	So, now from 60 degrees, which I would consider fully warm, we should not need warm up enrichment at that point, we've got all zeroes.
13:27	Now, I want to just make sure you understand here, this is not the process of tuning the warm up enrichment table, this needs to be done after the engine is properly tuned because the numbers in this table actually act on top of our base map.
13:42	The other aspect here is it's not uncommon to add additional fuel at higher operating temperatures as well as a bit of a safety.
13:50	This is personal preference, we're not really dealing with tuning this table in our worked example, I just want to mention it, seeing as I've come here and shown you what we should be at least looking at before we start tuning.
14:02	Alright, last couple of tables we're going to look at now are under our engine protection.
14:07	So, we can see engine protection is right here, we'll open that up.
14:10	And we'll start with our RPM limit.
14:14	So, couple of things we need to consider here.
14:17	The first and most important is our RPM limit mode.
14:20	We can double click on this, we can see we can turn that off.
14:23	Not entirely sure why we would want to turn our RPM limit mode off.
14:27	We've got ignition cut, fuel cut or disabled.
14:31	Ideally where possible I would always set this as a fuel cut because it is the most gentle mode on the engine.
14:38	Ignition cuts can end up causing unburned fuel and air to combust in the exhaust.
14:44	This can play havoc with the valve train on some engines.
14:47	It can be a very costly accident if you're not careful.
14:51	So, fuel cut is always the safest option and we will leave that there.
14:56	We've got advanced mode which gives us a lot more control over the rev limit.
15:00	In most instances this will not be necessary and again for simplicity, we're going to leave that off.
15:06	So, what we'll now do is actually have a look at the actual RPM limit table.
15:11	So, we can do that by pressing the escape key and that will bring up our menu and RPM limit table one.
15:18	Alright, so we can see that our RPM limit here is relative to engine coolant temperature.
15:24	Now, at the moment we've got, in our normal operating range, the RPM limit is set to 7700.
15:30	There's a subtle aspect with the way Lynx limiting is done that can catch you out.
15:36	They're at soft limit or control range which you can adjust if you enable the advanced mode, by default it's 200 RPM.
15:44	But this begins before the number in the RPM limit table.
15:48	So, what I mean by this is with a number of 7700 RPM in here, it will start soft limiting 200 RPM prior or at 7500 and by the time we're at 7700 RPM we would have a 100% cut.
16:02	So, just keep this in mind because you may notice that the RPM limit starts to activate or appears to activate before it should and that is why.
16:13	It is actually a known behaviour and that is how it should operate.
16:18	What you can do with this while you are just getting started, it's not a bad idea to just set this to something quite conservative, maybe 4500, 5000 RPM, just, so the RPM is not going to get out of control if something's wrong, particularly with drive by wire throttle engines, if the throttle ends up being way more open than it should be by some miracle, this can just protect the engine.
16:42	If you do this however, just remember that you've done it because it can catch you out and it probably will later in this worked example once you start trying to rev the engine higher.
16:51	So, we'll leave that there at the moment, it's nice and conservative.
16:53	You can see also that above 110° the RPM limit is conservatively dropped down, probably arguably too conservatively, but this is just for engine protection essentially and that basically prevents the driver from driving the car too hard while it's overheating and damaging it more than it otherwise could be.
17:16	Alright, RPM limit is dealt with, let's have a look at our last table which is our manifold absolute pressure limit, our boost cut table.
17:23	And exactly the same behaviour goes for this table.
17:27	Again you can access this through the advanced mode and we'll actually come back to that.
17:32	You can see again you've got the same controls here for the limit mode and again, same reason, fuel cut is where I would go with this.
17:39	Let's just activate this advanced mode for a second.
17:42	I'm not gonna go through all of the settings.
17:44	But what we can see here is the limit control range which is what I was talking about for our RPM limit as well.
17:50	I mentioned for the RPM limit the control range is by default 200.
17:54	For boost, by default it is 10 kPa.
17:57	So, I'm just gonna turn that back off now.
17:59	And now if we go back to our map limit table, what this means is that we will begin boost cutting 10 kPa below the numbers in this table.
18:09	And I just know that this is something that catches out a lot of people, a lot of tuners who are new to link.
18:14	So, again what we want is conservative numbers in this table, I'm not gonna really worry about the coolant temperature at the moment.
18:21	So, let's just start by setting these to 200 kPa.
18:25	So, one bar of positive boost, well we now know that we'll actually start boost cutting at about 90 kPa, so what we can do is bring that up to So, that will now start boost cutting at one bar of positive pressure.
18:40	Nice and conservative and again just like with the RPM limit, we do want to make sure that we keep this in mind, so that we can address this before we start trying to raise the boost.
18:50	Now, I would say this is really really critical to make sure you're conservative with this because particularly if you're dealing with a car that's been built by an owner, or it's a bit of an unknown quantity, time and time again the most common mistake I saw with cars that I was professionally tuning is boost control setups that had been incorrectly installed.
19:10	And the number of times I'd get on the dyno with all of my boost settings trying to aim for wastegate boost or our minimum possible boost and you'd start doing a ramp run and the boost would just ramp up towards infinity before the boost cut saved it, I would say four out of every five cars I tuned, that was the status of them.
19:29	So, it's a very common mistake for people to make and this can be an absolute lifesaver to save your engine, so make sure that you've got that set up.
19:38	Alright, we'll press F4 now to save those changes and also what I should have mentioned right at the very start of this module, because I didn't at the end of the last one, remember we had turned our fuel mode off, we must turn that back to sequential.
19:55	Otherwise, when we do get to the point where we start the engine for the first time, it's obviously, not going to start.
20:01	So, we've got numbers into our key tables here that are nice, safe and conservative.
20:05	We've got nothing to worry about here with our engine protection strategies, those are also set up, let's move on with the next step.