Crazy ignition timing - Evo VIII vs IX
 

I can't get over the crazy high ignition timing you guys are able to run on your high octane maps. I've been trying to figure out the options - no insults here...

1. Your cars are knocking
2. Your ECUs are pulling out the timing so you are not running what your maps say
3. The Evo VIII takes more timing than the IX because of no MIVEC?
4. Your fuel is amazing
5. You run less boost
6. Some of you don't have the road space to repeatedly boost your car as hard as you can drive for mile after mile

8 degrees on 98 RON on my IX with 3" decat exhaust and Walbro would detonate it to pieces during my spool up that hits 26 PSI. It flashes to 0 and then climbs to 2 or 3 before ambling up as revs increase. My AFRs are sensible (12:1 during spool, 11.5-11 on full boost) and the car makes excellent power and torque on the road and on the dyno. So I guess I'm happy, but there are huge disparities.

Comments/discussion good/bad welcomed.

I see what you are saying but you need some decent tuning. I can run 26-28psi consistently in 100 degree weather at 3100ft and 91oct and my car does not knock.

I paid a professional to tune my car to my needs(91oct+ methanol) daily driver. Tuning is the issues here.

I don't understanf number 6. We don't have roads to build boost? How much distance do you need? I live in the desert, there is plenty of long roads around here..

I also disagree with number 4. The fuel in Europe is better.
Number 5 is questionable. Some people run high boost and some other don't, depends on mods and tuning.

Carlos

I used to be a professional tuner before I got too busy as a doctor :D I could fling octane at it and run crazy timing, but I've learned by popping headgaskets and cracking ring lands in the past...

There are only three variables (fuel, boost, timing) other than VVT which can be played with on the map. Fuelling and boost are fine, and if I run more timing it either knocks or the ECU pulls it. But the car makes the power and torque beyond what the previous pro-tune on it did and doesn't det where that did. I run more boost and less timing. Richer spool, leaner top end.

What do you expect, you have meth. That is just like running race gas. If it was 91 oct only then you would not get away with that.

It look to me like the timing must be re adjust. I am surprise about a couple of things, your gas is better and the temps there are cooler, you car should be very efficient. I personally drive my car under extreme conditions and enormous boost with ****y gas and high elevation and can't complaint on performance nor tuning. Don't forget I am also tune conservatively.


I still believe your issue is fine tuning. I can only compare my car and conditions with your car and conditions, if I have absolutely no issues of knocking on my car you should have even less issues considering your mods. It is the tuning mate!.

Carlos

I ran my car before the methanol and boosted very high with no knock. I know what you mean, my methanol should be into the equation however my tuning is conservative.


Carlos

There are more variables than just fuel boost and timing.

So you can run 28psi on 91 pump with no meth at all and you will get no knock?
Have you checked for knock on a logger, because that is very hard to believe, but who knows. I could believe it if it is done with the meth injection.

I never said I ran 28psi without methanol. Please show me where I said that.

Carlos

i would be looking closer into your fuel, the way octane is rated here stateside differs from most other places in that we use a combination of the RON (Research Octane) & MON (Motor Octane) to come to our final octane number RON+MON/2

as i understand it the RON is more effective in judging the low load properties of fuel where the MON is more effective in judging the fuels high load knock resistance.


http://www.millersoils.net/pdf_downl..._explained.pdf

Our 98 RON is the highest octane available in this area, there is a 99 RON that is a methanol blend. Anything higher octane is available to special order and $40-50 per gallon so prohibitively expensive. I gather that our 98 RON is about equivalent to your 93 PON.

I'm not sure what other variables there can be when mapping the car. Given that the spec of the car is stock plus turbo back exhaust and fuel pump and that is the way I want to keep it, then what other variables do I have at any particular RPM level on WOT apart from boost, fuelling and timing (and VVT on the IX)?

I'm also not sure how it can be the tune when I have fixed the variables I want to (boost and AFR) and am running knock limited timing. Since the car makes the power and torque (running 100 BHP and 60lbft over a stock Evo on the same dyno) I would say the timing is right. I don't think more timing is always better, cylinder pressure spikes can damage internals, by running more boost you can keep the pressure curve wide and flat and get a higher BMEP.

I have no knock problem because I've tuned it out. I started from the JDM GSR base map which is 3 degrees more advanced than the comparable USDM map, and I have retarded 1 degree on full load at 6000 and 6500 RPM. I've kept the stock fairly aggressive ramp down of timing as load increases.

My puzzlement comes when I see maps on here with 8s where I'm running 1s and 2s and getting enough knock counts that I know I don't want to be adding much more. I get slightly higher knock counts at lower boost levels or on part throttle - nothing worrying, but that does suggest my full load timing is safe. But it isn't always zero which suggests to me it isn't that tame.

I can see a benefit to running a flat area of timing in the load zones slightly below your WOT level now I've had to pull these areas to kill lift off det. But it scares me if your cars overboost right to 300% and still have an 8 degrees in there. If you have a boost hose or actuator problem I reckon that could grenade your motor. Hopefully the knock control will catch it, but...

I've also studied Vishnu's XEDE maps for various stages and I respect his tuning basically because what a lot of what he says makes sense to me. I notice he pulls timing in the high load areas on pump gas from even the stock USDM maps. Now that is compounded slightly by him pulling up to 15% from the MAF frequency on the piggyback. Now that would probably move the load by one column or so, and so be about 3 or 4 degrees. Funnily enough, that is about the timing he is removing - so in other words keeping the stock USDM map, and not running crazy boost with it.

I'm also puzzled that the stock ECU maps are supposedly so far retarded from what is ideal. Stock ECUs that run active knock control do often seem to be on the limit of knock from what I've seen but run low boost. Often power is made by decatting them, leaning off the fuelling and increasing the boost, with necessary changes to the timing to accommodate this. On many JDM ECUs you actually have to retard the timing quite a lot on Subarus with this sort of stage I change.

As you aware there are many factors that contribute to the car performance. I am in the same situation that you are in that I am not running near the timing that some are. However, my car seems to be happier running a bit more boost (22-23lbs peak) than most vs. more timing advance.

FWIW Al tuned my car and was upset that I was running the Irridium plugs vs the copper NGKs. He claimed that the copper NGKs were the way to go.

The bottom line is that there is more variation in "like" cars than you would think and one needs to find the right mix of parts and tune for your ride.

wow i see where your at i have a jdm evo 8 and my car likes to advance the timing a lot
here is on of my logs on 91oct:

Time,RPM,Timing,O2 1 Bank 1,O2 Trim 1 Bank 1

00:03.38,3426.0,11.0,0.92,0.0

00:03.68,3621.0,7.0,0.92,0.0

00:04.00,3855.0,5.0,0.92,0.0

00:04.30,4074.0,4.0,0.94,0.0

00:04.61,4344.0,5.0,0.94,0.0

00:04.92,4625.0,7.0,0.94,0.0

00:05.23,4875.0,7.0,0.94,0.0

00:05.55,5117.0,8.0,0.94,0.0

00:05.84,5348.0,8.0,0.94,0.0

00:06.15,5590.0,8.0,0.94,0.0

00:06.46,5824.0,11.0,0.94,0.0

00:06.77,6023.0,12.0,0.94,0.0

00:07.07,6219.0,15.0,0.96,0.0

00:07.38,6449.0,18.0,0.96,0.0

00:07.69,6660.0,19.0,0.94,0.0

00:08.01,6848.0,19.0,0.94,0.0

00:08.31,7023.0,20.0,0.94,0.0

00:08.63,7191.0,22.0,0.94,0.0

00:08.93,7352.0,22.0,0.94,0.0

00:09.23,7516.0,23.0,0.94,0.0


and this is using the basemap from the vishnu site.
vishnu is very conservative.

Example timing at 20 PSI, 11.5:1 AFR, 98 RON:

4000 8
5000 8
6000 10 (knock count of 1 from 5600-6600)
7000 16

At 26 PSI (rolling off at the top to 20), low-mid 11s AFR:
4000 1 (with a knock count of 1)
5000 6
6000 9
7000 15

I think these are tame compared to what is quoted on here on pump fuel, especially on the Evo VIIIs.