Serious statement:
I have not found proper information how to tune ignition (all fields in low cam and high cam tables in any sw U use) when U are dyno tuning a car.

Add or pull a couple of degrees and dyno again then add or pull more then dyno again method is BS. We pulled and added 2-4 degrees but minimal changes measured in performance. Stock knock sensor sux according to many people. My MSD Knock Alarm is quite useless, because it is picking up too much noise or it is impossible to set its sensitivity, also I can not log its readings (like AFR). I do have an EGT sensor installed, but it is slow and I can not log its readings, I use it to avoid too hot exhaust gases.
I know my knowledge is very limited, just like my equipment, but THERE IS NO GUIDE AND INFORMATION AVAILABLE HOW TO DO IT PROPERLY.
I mean sg. like get XY stuff, buy that sw, install these like that, measure this, log that and adjust accordingly... U can find it for AFR tuning, but not for ignition.

Share good info on this if U are aware of any! (sorry for bad english of mine)

Edit> I will come back in 2 days and check whether we have a FAQ here or a lot of BS has bees generated.

 

Good topic.

I will help you with this offline.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Master of the Universe &raquo;</TD></TR><TR><TD CLASS="quote">Good topic.

I will help you with this offline.</TD></TR></TABLE>

Hence why no one can find any info about it

 

Just sign up at EFI University. Professor Ben Strader

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Master of the Universe &raquo;</TD></TR><TR><TD CLASS="quote">Just sign up at EFI University. Professor Ben Strader </TD></TR></TABLE>

thats all great but there are a lot of people who would benefit from a little info here. I understand that you have put your money and hard work and experience into knowing this stuff, but I am definitely interested now and slightly disappointed to not be able to find anything on it (unsurprisingly, google has nothing for me here ) lol

 

ive been on the dyno and tuned ignition but only at full throttle so take that fwiw

but on my car (NA) i found no gain by adding or subtracting timing values from my full throttle columns from my stock timing map

on my buddies turbo car who was running a basemap with some pretty retarted timing we added timing and it made huge jumps in power up to a certain value and then it stopped making power past that so we backed it back down.

again im no expert but it seems to me that if the fuel type is the same (burn rate) and the rpm is the same then timing values prolly wont vary too much from a stock ign map because your really just changing the start time of the "bang" and trying to line it up with the most effective crank angle for the most power. retarding timing isnt really tuning to me, it seems more like a "fix" for detonation in high compression engines with lots of cyl pressure or boosted engines.

again im not downplaying piston dome or chamber profiles, compression/cyl pressure, mixture, or any of that im just saying that there doesnt seem to be alot to gain if you have some form of a good timing map to start with.

please feel free to chime in and add or correct anything i said if you have any experiance

 

having thought about it i realized that port velocity would also play a pretty big role, since you want to have the "bang" occur during peak cyl pressure for max power so somthing with a lazy port might want to be lit off at a different time. i suppose this would affect low RPM operation on engines like mine more than a vtec engine with properly sized cams and ports.

 

http://www.motec.com

 

There used to be some helpful threads at the pgmfi.org forum. Your might have to search around a bit. I'd start with "tuning timing" and "MBT"

 

http://racingsecrets.com/spark_plug_reading.shtml

Do higher learning. Not Donf says this or Rocket says that.

 

I recently purchased a book about this igition timing, give me a few hours and i'll write some neat stuff up..bought this kool book at books a million called " How to build a powerful honda" basically in a nut shell, all motor wise, you need to create more cyl pressure to make power.. because unlike v8's we hardly have any displacement, specially if ur tryin to make stock block power. i'm at my mom's right now but when i get back to my house, i'll write some **** up for you to hopefully help you with some tuning.

 

On my old B18C5 engine 81x87.2mm 11.5:1 comp engine, the local tuner did at WOT a max ignition of 32' @ about 7000rpm then slowly dropping back to 30' at peak rev.

On my new setup engine 85x87.2 13+:1 comp engine, the local tuner said due to the high compression, i should run only max ignition of 24-25'. I think it is very low and wont make full potential or power out of the new build.

What do you think then???

 

NO good info on pgmfi.org

Please, share good info here in order to help the entire NA Honda builder community (what must be the main purpose of this forum).

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chris2000 &raquo;</TD></TR><TR><TD CLASS="quote">On my old B18C5 engine 81x87.2mm 11.5:1 comp engine, the local tuner did at WOT a max ignition of 32' @ about 7000rpm then slowly dropping back to 30' at peak rev.

On my new setup engine 85x87.2 13+:1 comp engine, the local tuner said due to the high compression, i should run only max ignition of 24-25'. I think it is very low and wont make full potential or power out of the new build.

What do you think then???</TD></TR></TABLE>
the engine will want what it will want disregarding what anyone tells you... all engines are NOT equal...

 

i'm not an expert either but my view on this is to make use of time based low latency datalogging devices such as those from Innovate.

take some time and read pages 17-24 of <U>this manual</U>. Measuring Ignition Advance.

i have yet to try with mine as soon as i finished assembling my motor.

 

I'm claiming to be no expert, but after hours of writing and researching myself because i know timing is alot of hidden power, i care to share what i've found.. threw ht, superhonda, and tons of books on tuning / building hondas


Optimum timing of the spark is the number of crankshaft degress that builds peak cyl pressure at 12~14 degress ATDC

Being all motor, (Like me, and others in this fourm) Power isn't just based upon stroke/bore.. although it is easier to make power like that, I myself am tryin to make the most out of a stock block(as well as others) to make power from a stock block you must find a way to increase cyl pressure.
As the engine speed increase, there is less time for the flame front to consume the fuel and build pressure in the cyl. Creating the reason to advance igition, however flame speed increase in exact proportion as engine speed.
Theoricity this means that a turbulence incerase in the combustion chamber, more of the fuel turns to vapor, allowing it to react witht he oxygen more quickly. due to this relationship, the amount of advanced required is stable.

to do this is two stages, one setting your base timing with your dizzy, at 16~18 degree's, to maximun poteinal would be to set it to 16 TDC. Adding initial timing advance is what is needed to balance engine rpm and peak cyl pressure.
From 2k ~3k rpm more crankshaft degress from the point of the ignition are required for the cyl pressure to reach MAX then it does say above 3.5krpm.
This means you have to steady feed in timing advances.
As a normal rule, and take into consideration every engine is different but use this as a baseline , it takes 20~32 degress at 6,000rpmms to reach maximum cyl pressure for a N/A engine. generally speaking honda put around 28~30degress advanced on the p30~p72 maps around 7k rpms..so they were right on the money..for the lower part of the cam maps you could tweak and gain alot of power same with the high cam.. the igition maps are pretty based, after 7k you tend to want to start running things back.. but then again i've seen motors, and mine is one of them, at around 8100rpms it was asking for almost 32 degrees.. it really depends on your mods, the way your cams are setup, and ur current timing.. it all depends.. using the stock igition maps make a few pulls and record data. Try retarded some of the ignition first, to see if any gains can be made, by like 2~4 degrees, if none is made, advance it 2~4 degrees and use this as a stepup..it isn't hard to tune timing just "time consuming".

 

H-T input on this topic seems ~ZERO to me, meaning none uses a sophisticated method to tune ignition maps.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by koczeka &raquo;</TD></TR><TR><TD CLASS="quote">H-T input on this topic seems ~ZERO to me, meaning none uses a sophisticated method to tune ignition maps. </TD></TR></TABLE>
WTF?!? did you not just read what i said, thats the WHOLE bases of tuning ignition read what i said..it gives you a starting point..

 

I have read that, sorry...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IntegraType-R &raquo;</TD></TR><TR><TD CLASS="quote">I'm claiming to be no expert, but after hours of writing and researching myself because i know timing is alot of hidden power, i care to share what i've found.. threw ht, superhonda, and tons of books on tuning / building hondas


Optimum timing of the spark is the number of crankshaft degress that builds peak cyl pressure at 12~14 degress ATDC

Being all motor, (Like me, and others in this fourm) Power isn't just based upon stroke/bore.. although it is easier to make power like that, I myself am tryin to make the most out of a stock block(as well as others) to make power from a stock block you must find a way to increase cyl pressure.
As the engine speed increase, there is less time for the flame front to consume the fuel and build pressure in the cyl. Creating the reason to advance igition, however flame speed increase in exact proportion as engine speed.
Theoricity this means that a turbulence incerase in the combustion chamber, more of the fuel turns to vapor, allowing it to react witht he oxygen more quickly. due to this relationship, the amount of advanced required is stable.

to do this is two stages, one setting your base timing with your dizzy, at 16~18 degree's, to maximun poteinal would be to set it to 16 TDC. Adding initial timing advance is what is needed to balance engine rpm and peak cyl pressure.
From 2k ~3k rpm more crankshaft degress from the point of the ignition are required for the cyl pressure to reach MAX then it does say above 3.5krpm.
This means you have to steady feed in timing advances.
As a normal rule, and take into consideration every engine is different but use this as a baseline , it takes 20~32 degress at 6,000rpmms to reach maximum cyl pressure for a N/A engine. generally speaking honda put around 28~30degress advanced on the p30~p72 maps around 7k rpms..so they were right on the money..for the lower part of the cam maps you could tweak and gain alot of power same with the high cam.. the igition maps are pretty based, after 7k you tend to want to start running things back.. but then again i've seen motors, and mine is one of them, at around 8100rpms it was asking for almost 32 degrees.. it really depends on your mods, the way your cams are setup, and ur current timing.. it all depends.. using the stock igition maps make a few pulls and record data. Try retarded some of the ignition first, to see if any gains can be made, by like 2~4 degrees, if none is made, advance it 2~4 degrees and use this as a stepup..it isn't hard to tune timing just "time consuming".</TD></TR></TABLE> Well your first sentance is correct. But peak cylinder pressure is decided by compression, chamber design, and the fuel used. Leaving the first 2 as a constant, if you switch from Sunoco Blue to VP 15, you will have to change timing. Different fuels have different burn property's that will change wher the peak cyl. pressure is.
Also learm to read a spark plug, this will help tell you cyl. temps. Next go dyno your motor and figure the timing for what you are using. Shell 93 here in FL. will have a different timing number than Shell 93 in the NE as they use more MTBE's. I have no idea what the number would be for Shell 91 in CA would be, except less.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DonF &raquo;</TD></TR><TR><TD CLASS="quote"> Well your first sentance is correct. But peak cylinder pressure is decided by compression, chamber design, and the fuel used. Leaving the first 2 as a constant, if you switch from Sunoco Blue to VP 15, you will have to change timing. Different fuels have different burn property's that will change wher the peak cyl. pressure is.
Also learm to read a spark plug, this will help tell you cyl. temps. Next go dyno your motor and figure the timing for what you are using. Shell 93 here in FL. will have a different timing number than Shell 93 in the NE as they use more MTBE's. I have no idea what the number would be for Shell 91 in CA would be, except less.</TD></TR></TABLE>
thx donf for adding / clearing up some mix ups,
i use shell 93oct v-power / chevron supreme down here only, but i've seen tunes where they both make different numbers..
Chamber design will also play a big role i'm assuming because it defines the burning of the fuel process and how fast it burns... i think what donf is tryin to point out is that, every motor is different because of the varibles that apply, u gotta try things out for yourself there's no SET rules to this..its what works.

 

yeah there are no set rules, but the stuff you're talking about is not even useful.

yes we realize that you tune ignition timing to maximize cyl pressure. The OP wants to know the actual method of doing this. Read more of that book, all the stuff you posted is a bunch of science, which is fine, you definitely need to know, but some more applicable information is the goal of this thread.

The reason chamber design plays a role is because it alters how the flame travels, not the burn rate. The fuel used is what determines the burn rate.

I guess reading the plugs is a step in the right direction.

 

If you're not load cell tuning and just doing wot pulls then start by retarding all your values in the highest load areas of the map. Make a pull on the dyno to get a baseline.

Once you have the baseline advance each cell by a degree and re-dyno. Compare the graphs inbetween by overlaying them on the computer screen and anywhere the power did not increase, or increased very little... go back to the map and change the value of the corresponding cell back to what it was on the previous pull.

My guess is that if you are advancing it and retarding it a few degrees without seeing any changes, its already higher than it needs to be.

 

Answer the original question please:

How do U tune ignition on the dyno?
Not only @WOT, but all fields...

 

the rest of it and what you should do before the wide open pulls is called "load cell tuning"

By using the rpm holding of the dyno and your foot to adjust load, tune each individual cell the same way. start out lower on the timing and advance it degree by degree until you see the power output on the screen start to level out, then stop and back off a degree. You obviously can't do the whole map that way but you should be able to clean up the map to about 5k rpm doing cell by cell tuning. Once you set this up you'll see the map start to take shape and then you will interpolate or project the rest of the map in the direction that it is going.

After that do the wide open tests like I stated above and once you get that tuned you'll be able to see the full curve of the map and be able to interpolate and tweak in some of the harder to reach areas a little better.

This is all pretty general and assumes your fuel map is already setup and your engine combo and fuel choice were carefully thought out. Always start out with safe numbers and go from there.