Hey Guys,

Just a general question mainly aimed at the experts on here - C.Ludwid

Just wanted to ask the general rule behind the timing of a map.. i have used microtechs in the past and just wanted to understand a little better as to why in the haltech timing maps they arent static arcoss the whole boost and rev range?

I have been provided some basics from a local tuner and they look like the below - fairly basic numbers..

Then looking at a haltech map you get the increase in timing across the map and no actual static timing.. (pic below)


Is there any reason why i cant set up the tune like the above static numbers or am i going up the wrong path..

Is there any benefit of doing it like the attached pic over static timing per load point?

Is the way i am possibly attempting to time the engine against the way a haltech works?


The motor for now is just a stock 12a tall port running 7psi until i build my new engine.. Injectors will be 550cc primarys and then 1200 RCI low impedence.

Open to any advice guys..

 

static timing is the locked timing value when you apply timing lock for testing,, this is the minimum number the timing will get to


important differences to note---

the microtech sees the TPS threshold as a switch,, and so when the idle flag is up,, will jump onto a dedicated locked idle map to give a steady idle that cannot hunt

if the tps is at 2% the flag is down and so it will look at the rpm table ,, and interpolate that with the load table , which is pretty much what the haltech does full time

as you can see ,, the haltech map you have posted keeps all the numbers the same in the lower rpm values
this is a trick to stop the idle hunting
,, it will stick in the same timing regardless of vacuum fluctuations until rpm is at a point that it is obvious even to the ecu that it is no longer trying to sustain an idle

the micro sees things a little more digitally on/off ,, idle is either on or off and the flag falling is the trigger for the low speed accel "pump" enrichment
because of this digital "flag" arrangement with a narrow scale tps ,, the micro must use a rapid vacuum change with rpm flag to trigger the 2nd " high speed" acell pump function
--- very ambiguous actuation of the secondary fuel pump enrichment is the price you pay for that digitally switched smoother idle
,, a bug that often comes to play at about the point the secondary staging occurs
,, and a reason why they can be so inconsistant to tip in throttle movement around that point

the haltech on the other hand,, has no "switched" idle ,,the tuner resorts to that trick with all the low rpm values the same regardless of vacuum
importantly it uses a full range tps,, and senses the high end throttle pump by the rapid change in the tps signal ,, from whatever throttle angle , a much more reliable trigger command for the accel pump enrichments



--------------------
the load theory -
at high vacuum, timing advance is needed to excite the inefficient filled charge , this is to speed up the burn rate
as you move to WOT,, chamber filling is more efficient and the timing lead in assistance required drops to zero,,, under boost chamber filling is past 100 % efficient and so you pull timing out

the micro map you have for timing retard isnt too bad under boost
, looks like one of my 8.5:1 rotor maps that is basically initially offset by 2 psi then is 1 degree for every 2 psi up to 10 psi then 1 for 1 for boost above that

if i use higher comp rotors i generally leave the initial 2psi without retard offset ,, but go 1 for 1 from 4 psi
ie ,, 18 psi = 16 degrees retard from load ( 0 vac ) @ 26 degrees = 10 BTDC

------------
the rpm theory ,, the rpm map has a curve shape from idle to 2500 rom ,, where thing begin to get onto the port,, and this timing value is sustained within 1 or 2 degrees until past the rpm at which peak TQ occurs
and from there upwards the timing should start to climb once again
( known as a z curve )

ie,, if a ported engine likes to idle at 5- 10 BTDC ,, if will be around 24-26 degrees ( comp ratio depending ) by 2500 rpm
this value will sustain itself till the motor begins to rev beyond the optimum port rpm
then,, the timing value ( at zero vac ) may just climb a few degrees upwards to 27 by 7000 rpm and 28 by 9000 rpm ( example only )

this reflects that there is not enough period at rpms to burn all the fuel in time to apply effort to the crank

 

Thanks for the update Bumpstart..

I guess what i really am asking is a haltech be set up with static numbers or shall i just use the map ive screen shotted..

Also ive got a 2 notch pulley from a tall port 12a which according to my manual is 0 TDC and 20 ATC - i have reflected this in the setup menu..

As you can see im struggling a bit to get my head around this ps1000 when there is little help over here in the UK..

 

Didn't I email you on this subject?

What you see in the MT "map" is only part of the story. MT and Haltech do effectively the same thing, they just have two different ways of visualizing it in the front end software. What you're showing is the MT base load map. There is also an RPM offset that works off of that base map. The Haltech does the same thing, it just represents it differently.

I've sent you a base map. Without the full MT map I can't say how close what I sent you is to the MT settings you're looking for, but my guess, based on what you've posted, is that they're fairly close in most regards. What I have sent you is certainly safe to run, though it will likely leave some power on the table.

The first thing you need to do before proceeding is zero the timing. If you have a mark on the pulley at 0*, then set the timing lock in the ignition setup page to 0* and trail at 0*. Crank the engine with the fuel shut off and check that leading 1 and trailing 1 fire at 0*. L2 and T2 should fire at 180*. Manipulate the trigger angle and/or tooth offset to get them to line up. Once they line up, unlock the timing in the ignition setup menu and start the engine. There are many threads on zeroing the timing. This procedure needs to be followed in order to ensure you're getting the spark advance that you program into the ECU. If you're familiar with the MT, it's the same procedure, you just have the option with the Haltech to choose the timing lock advance.