jreynish

iTrader: (2)

Ok here are the tools that I have to see a/f and inition,
Haltech E6X
Stock Ignition coils
550cc Primary Injectors
1600cc Secondary Injectors
AEM WB02 Guage wired to datalog in the haltech
Blitz EGT sensor and guage
Autometer Narrow Band O2 guage

Now I have read the haltech manual and many other tunning resources online, and I bought how to tune and modigy engine management systems by Jeff Hartman.
Now I have a very good grasp on air fuel ratios and such, however I want to know how to guage whether i need to advance or retard the Timming. Please help me out!
Give me pointers or the theory behind it or just rules of thumb I am sure that all good knowlege would be greatly appreciated.
Thank You
Jeff

RETed

Advance the ignition until you hit detonation and back it off.
That's it.
The only useful tools that are easily available are the EGT gauge and a dyno.
The EGT will show how hot the exhaust is; if you have a clue on how hot the EGT should be running, then you shoot for that EGT number.
Keep in mind that the EGT has a lag time, so adjust accordingly.
The dyno will show the onset of detonation when power starts to drop.
I typically jack down 3 to 5 degrees from this "limit" from detonation for street vehicles.
For rotaty engines, advancing the ignition does not have gains like piston engines, so even a 5 degree retard will maybe lose 3 to 5 hp in most cases.
The safety factor is a lot more important to me that trying to get that last 10% of power...

As a side note, ignition maps are different from car to car, so to get the most out of your engine, don't expect someone elses ignition map (hell, the entire map) to work the best for you, even with identical mods.


-Ted

jreynish

iTrader: (2)

I do realize the theory behind it based on countless sources of reading. but for instance how do I know when I am reaching detonation? i do intend on doing my final tunning on the dyno but since the nearest dyno is like 9 hours away... I want to get her descently tuned on the street to get there without worries.

RETed

1) You'll hear it.
2) The EGT will start to skyrocket.
3) The dyno will show a drop in power.


-Ted

jreynish

iTrader: (2)

I will hear it like, it is my understanding that one knock is enough to through an apex seal?
I would rather not have that happen, The dyno I understand the power will drop suddenly so I have no problem there.
But with the egt it has a lag how bad is the lag, I should be able to keep my ear to the car and watch the egt and I should be good ?
is there a rule of thumb for increase in boost and a retard in ignition?

GUITARJUNKIE28

ever try hooking the knock sensor up to hte stereo? i've heard of guys doing that with one of those cassette adapters. i've heard of a company that makes a unit like that--it's pre-eq'd so all you hear is the engine, then you just wear some headphones while tuning.
it's supposed to work really well. it may be my next investment.

jreynish

iTrader: (2)

so you mean the stock knock sensor? how would that be hooked up to the stereo?
I mean where does it go? there is only one wire comming out of the knock sensor, and it owuld require two to even connect it to mono onto the stereo. Any toughts
Thanks
Jeffrey

jreynish

iTrader: (2)

Guitarjunkie28,
thank you for your suggestion It led me to find this I hope this might help you out too (that is assuming you didn't already read it)
http://www.autospeed.com/cms/article.html?&A=0353
I hope this will work for me while driving.
Thanks again.
Jeff

GUITARJUNKIE28

that's it
although i haven't tried that one, i've heard nothing but good stuff.

GUITARJUNKIE28

oh wait.. that's not the one i was thinking of, but same thing anyway

jreynish

iTrader: (2)

do you tune while you guy's are driving on the street or on the dyno, or do you get someone else to drive whille you tune, because I am having trouble trusting anyone to drive my car whille I tune.
any suggestions on street tunning hints tips.

GUITARJUNKIE28

i'll usually pop on the freeway at 2 or 3 am to get the cruise down, for the higher rpm, high boost stuff, i'll datalog a run, then pull over and make adjustments.

for the REALLY high hp stuff (450+) i'll get it rich, then fine tune it on the dyno-as that hp level isn't exactly safe when you've got to worry about laptops, displays, and a bunch of other crap flopping around in the car.

RETed

The EGT lag is somewhat of a myth.
You'll see it start to jump before any serious damage happens.
UNLESS, we're talking about serious detonation.
Specifically to ignition timing adjustment, go up in 2 degree increments slowly.

Yes, there are rules of thumb for retard versus boost, but this doesn't give you the best ignition map for power.

There is also max and min ignition timing at boost, and I think a thread is in here about that.
Basically 15-degrees is what you want to shoot for.
You can back it down to about 12 or 13, but any less is too much.
Ramp up ignition advance up to *peak torque* RPM and then ignition advance flattens out.
Try do a search ignition advance in here - the threads are around.
I keep a general ignition map in my head and fine-tune adjust after the fuel maps are taken care of.


-Ted

Bond

Holly cow, did you say advance till you hear a knock? Have fun with that one, Try setting your afr's first, then start ajusting your timing. Use the conservative timing maps your hearing on the forum ie: 12=15 deg under boost. Watching the egt slowly increase the timing till you quit producing power, this may take some time on the dyno but wont end up with needing a new engine. The egt reading you get are going to depend on where your sensor is mounted as well, downpipe or manifold. My best advise would be call a respectable tuner and ask them about your setup, this forum is full of useless info.

mike

RETed

Why don't you reread my posts before claiming I said that.
I did NOT say to advance until you hear knock - get that straight.
I said to advance until you hit detonation - detonation does NOT equal to knock.
If you think they are the same thing, then you need to education yourself on the differences on both.

A very well-known shop in the U.S. uses a J&S Safeguard calibrated for a specific engine.
They will advance the ignition timing until the J&S display lights up.
Can you HEAR this detonation?
No.
Is it knock?
Technically, NO.
This is NOT audible detonation - "audible detonation" is what most people call knock.

A dyno will easily show the drop in power from inaudible detonation.
This is your limit.
You cannot hear this inaudible detonation, but it easily shows up on the dyno.

This also shows up on the EGT as slightly elevated EGT's, and it won't be stable.
The nature of detonation is uncontrolled combustion, and EGT's will always start to rise (noticably) when you do hit detonation (from overly advanced ignition).

Yeah, you got that right.

Bond

When i get to 12,000 posts i should understand the difference in knock and detonation.

CCarlisi

Great info Ted. I noticed you said timing should increase until torque peak and then flatten out. I have had my car tuned by a couple people in the past. One of them did just what you suggested. Another tuner flattened timing out at the torque peak but then continued to advance it from 6500rpms to redline. Some people have said this is a SAFE way to broaden the power curve, but the tuner that favors flat timing told me the gains from advancing timing after torque peak are minimal and it causes the egts to increase. Can you tell me why you favor the flat timing approach. As rpm increases there is less time to complete the combustion process, therefore theoretically I would imagine that what works at say 6000rpms would not be ideal for 7500.

jreynish

iTrader: (2)

ok so With the setup on the website I posted earlier in the thread it should be able to give me that advance notice?
Thank You
Jeffrey

RETed

If you're assuming that, no wonder you're confused.


-Ted

RETed

To tell you the truth, I just flatten the timing out cause it's easier to "draw out".
In my experience, I agree that high ignition advance does increase EGT's - the increase in EGT is not worth the minimal increase in power.
Now, I cannot comment on "complete combustion", but what I look at is the EGT.
If the EGT is stable and not that high (I shoot for a stable EGT from 4,000 on up to redline), I'm satisfied with the ignition timing (map).


-Ted

jreynish

iTrader: (2)

I reiterate my earlier question dirrected to RETed, but anyone who is able to answer then feel free.
ok so With the setup on the website I posted earlier in the thread it should be able to give me that advance notice?
Thank You
Jeffrey

RETed

Using an EGT gauge to tune is dependent on the abilitiy and experience of the tuner.
I know what to look out for, and I know when it starts to get dangerous.
It's hard to explain this in text, as there are a lot of other factors you need to remember - this doesn't help that not all EGT gauges measure identically, although they are supposed to.
Different cars generate different EGT numbers, and I note this everytime I touch one.
The key to using an EGT is to be able to spot *trends*.

I learned how to use an EGT gauge by watching an EGT gauge operate on a near stock RX-7.
This gives you a good idea on what the EGT is supposed to display at any one time.
I don't really want to go into a detailed dissertation on how I use an EGT gauge, because I do charge for my services.
Yes, this is one of my "trade secrets".

Personally, I haven't killed any engines due to a lagging EGT gauge, with the exception of one instance which was the fault of improper ignition timing control.
No, a wide-band wouldn't have caught it either.
That engine let go with no warning.


-Ted

jreynish

iTrader: (2)

That is fair enough the info you have given me added with the theory gives me a good idea anyways.
I also respect your "trade secrets".
But thanks for sharing everyone. I knew the theory behind things but didn't know exactly how to apply them.
Thanks
Jeff

p51020b

Detonation is pinging is leaning out is uncontrolled combustion IS a bad idea.

Hello, the only reason i joined this forum is to state that Reted is clearly WRONG.

Detonation... audible or not is causing damage to your engines. Do not tune motors to detonation, then back em off a notch... that is just silly. Especially with a rotary, where as much as i hate to admit it, dont cop pinging like a piston engine.
I have 2 posts after this one, and i know this how could someone with 12000 posts not know ? or maybe he is just heeps used to feeding all you fella's a load of crap, and thinks he can change the laws of tuning .... he must be really smart.

Detonation is uncontrolled explosions, due to poor ignition / fuel tuning. This fuel is igniting before it should, causing the rotor so much stress it jumps around in there. So if you cant hear it its ok ? WRONG. If you are not too sure about this topic see your local Professional tuner, dont listen to a Hack in a forum to tell you how to blow your motor up. im sure we can all do that.

Now, ill probably never be back to this forum, i was just so intrigued to see that no-one in here was arguing with that reted clown (with the exception of Bond) . Maybe it is time for him to hang up his 12000 posts, and go build a car or something. Obviousy all his time is spent on the key board.
Thank you for your time.

GUITARJUNKIE28

actually that's pre-ignition.

why join a forum to show everyone you're a dick?