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What kind of timing advance are you guys running?

RYU said:
What total timing are you guys running? I'm assuming you're somewhere between 34 and 38 degs. Also what fuel and how many pounds of boost?
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I thought the idea was to RETARD your ignition timing when intake temperatures and boost increases.

(I mean, retarding the moment ignition sparking to a point usually AFTER Top Dead Center of your piston).
 
MvM said:
I thought the idea was to RETARD your ignition timing when intake temperatures and boost increases.

(I mean, retarding the moment ignition sparking to a point usually AFTER Top Dead Center of your piston).
Click to expand...

You retard timing with boost and temp increases, not typically after top dead center though. You also increase timing with RPM, this is due to the fact that the piston is moving faster but the combustion even takes the same amount of time so you ignite earlier to compensate for the speed.
 
E-Nough Logic said:
You retard timing with boost and temp increases, not typically after top dead center though. You also increase timing with RPM, this is due to the fact that the piston is moving faster but the combustion even takes the same amount of time so you ignite earlier to compensate for the speed.
Click to expand...

Thanks for the explanation.

So, if I get this right:
FIRST: you advance ignition timing as RPM rises because at higher RPM your pistons travel faster and you have less time to burn your fuel mixture. So, in effect, you simply start earlier.
SECOND: Then, second, you retard timing because of the increase in boost to avoid detonation.

So in effect, first you advance to compensate for the rising RPM and temps and then your retard again for boost and temp.

The net effect of these plusses and minusses can be both positive or negative compared to your idle ignition timing, depending on the circumstances.

Did I get this right??
 
RYU said:
I'm at 33-34 degs total timing on 91 CA gas with a stock Autorotor 7psi blower... I know 34 degs sounds crazy... We all think so but that's what my HKS FCon is saying and we're near the knock ceiling on pump gas.
Click to expand...

Two things I can think of for your situation:
1) Weren't you experimenting with meth or water spray post-supercharger (or pre)? Is it meth mixture or water, and what is your flow rate/RPM?

2) Didn't you go to a thicker HG? I hope not. The combustion inefficiencies due to increasing the squish clearance would require artificially increasing the timing.

Dave
 
So the tuner of my car is the one that tunes the FXMD time attack car. He's been very generous with his time and I consider him a friend. We *all* (him, I, you included) agree that 33-34 degs is insane and we honestly think there is something that's not being read correctly, hell.. maybe even belt stretch at the higher RPM. I really don't know... Again, we're tuning based the limits of knock. I could very well plug in an AEM in there and it could read 28 degs but all the NSXs on the HKS standalone seems to exhibit the same readings.

So dynomike - so what kind of timing do you put in for most CTSC on a standalone with our 91 oct gas?

- - - Updated - - -

Mac Attack said:
Two things I can think of for your situation:
1) Weren't you experimenting with meth or water spray post-supercharger (or pre)? Is it meth mixture or water, and what is your flow rate/RPM?

2) Didn't you go to a thicker HG? I hope not. The combustion inefficiencies due to increasing the squish clearance would require artificially increasing the timing.

Dave
Click to expand...
1. i'm now spraying post blower using the smallest nozzle (180 to 250 cc/m) I could find. The flow rate is very low as I have the spray set to start at 5psi but max out in pressure at 7psi. I'm trying to spray as little as possible while still maintaining the most amount of cooling. For example, I'm currently hovering around 140-145F IATs now. I could get this down to 100F but at almost 3 times the water volume which was really screwing around with the mixture and I was loosing power. The stability of the tune seems to be pretty good at 145F even under several consecutive of dyno pulls. I'll have to see if this creeps up at the track this summer. At the track w/o water I can EASILY achieve 200+F IATs but i've also had days where by the end of the session i'd be at 90F when it's 65F ambient and having the spray configured to deliver water at 1psi of boost and max pressure at 4psi. Just looking for some consistency and I think that's around the 130-140F range. More testing is needed... I'm not running any meth btw.

2. My new cometic HG is the stock thickness. Was considering the thicker HG but I really didn't like the potential change to the timing as small as it may be.

Are you fully tuned on your turbo setup Dave? Time for an update! :)
 
Even if it is a small nozzle, I think with the water you are slowing combustion speed too much and using a lot of timing to compensate.

That's one of the reasons to use a small amount of methanol in the mixture.

Stupid Question - Are you sure your VTEC is working?


Mine's not quite fully tuned yet.... I have an older TFX engine analyzer and my spark plug combustion pressure sensor bit the dust. I need to get it replaced, but it will be a few more months anyways before the weather cooperates for a drive!

I have to thank dynomike for the AEM2 and his excellent basemap. Without it, I would have been totally lost when trying to learn tuning basics. With a pressure sensor I can move to various cylinders and individual EGT monitoring, I feel comfortable playing with AFR and timing. Then, it is all the "driveability" tuning that takes up time.

Dave
 
RYU said:
So the tuner of my car is the one that tunes the FXMD time attack car. He's been very generous with his time and I consider him a friend. We *all* (him, I, you included) agree that 33-34 degs is insane and we honestly think there is something that's not being read correctly, hell.. maybe even belt stretch at the higher RPM. I really don't know... Again, we're tuning based the limits of knock. I could very well plug in an AEM in there and it could read 28 degs but all the NSXs on the HKS standalone seems to exhibit the same readings.

So dynomike - so what kind of timing do you put in for most CTSC on a standalone with our 91 oct gas?

- - - Updated - - -


1. i'm now spraying post blower using the smallest nozzle (180 to 250 cc/m) I could find. The flow rate is very low as I have the spray set to start at 5psi but max out in pressure at 7psi. I'm trying to spray as little as possible while still maintaining the most amount of cooling. For example, I'm currently hovering around 140-145F IATs now. I could get this down to 100F but at almost 3 times the water volume which was really screwing around with the mixture and I was loosing power. The stability of the tune seems to be pretty good at 145F even under several consecutive of dyno pulls. I'll have to see if this creeps up at the track this summer. At the track w/o water I can EASILY achieve 200+F IATs but i've also had days where by the end of the session i'd be at 90F when it's 65F ambient and having the spray configured to deliver water at 1psi of boost and max pressure at 4psi. Just looking for some consistency and I think that's around the 130-140F range. More testing is needed... I'm not running any meth btw.

2. My new cometic HG is the stock thickness. Was considering the thicker HG but I really didn't like the potential change to the timing as small as it may be.

Are you fully tuned on your turbo setup Dave? Time for an update! :)
Click to expand...

RYU is the tuning done by UMS? If so then you are fine. It is quite possible the reading are artificially high. If you were really that high you would have cooked your motor by now. Also which size engine do you have? I believe the 3.2 ran more timing than the 3.0. Ultimately you run what the dyno tells you to run. You combine that with spark plug reading and you can get to your correct safe timing.

My intercooled supercharger was tuned by UMS in 09 and again in 11 (slightly smaller pulley) to run around 25-26 degrees at 8 psi. If the IAT gets too hot then it pulls timing but the most I've ever seen it pull was 2 degrees. 420rwhp 317rwtq.
 
RYU said:
I'm at 33-34 degs total timing on 91 CA gas with a stock Autorotor 7psi blower... I know 34 degs sounds crazy... We all think so but that's what my HKS FCon is saying and we're near the knock ceiling on pump gas.
Click to expand...

My Guess is your piggy back is not reporting the correct value.

How does the piggy back control the ignition event, does it have direct control of the coil outputs or is it modifying the Crank Sensor input to achieve the desired ignition event.

If you where here in St. Louis I could log your OEM ECU and we would know commanded and corrected ignition numbers as long as the ECU is in control.

If the OEM ECU is in control then your target IAT should be less than 136* when the engine is in VTEC, anything above that and the OEM ECU will pull some timing, and will pull 2.5* by 172*f, and 3.00* by 190*f, and 3.5* for 208*f and above.

Stock timing levels at 7600 RPM VTEC Active are as follows:

Load% - Timing Value
00.00 - 38.50*
09.41 - 38.50*
18.82 - 38.50*
25.10 - 36.25*
31.37 - 34.25*
37.65 - 32.50*
43.92 - 31.25*
50.20 - 30.75*
56.47 - 30.25*
62.75 - 30.00*
69.02 - 29.75*
75.29 - 29.50*
81.57 - 29.25*
87.84 - 28.00*
94.12 - 26.50*
100.0 - 23.00*

Peak Timing Numbers at 100% Load in VTEC are as follows: (Ign Modifiers are applied to these numbers to reduce or increase Actual Ign)

RPM - Timing Value
0500 - 01.00*
1000 - 06.25*
2500 - 17.00*
4000 - 21.75*
4600 - 21.75*
4900 - 21.75*
5200 - 21.75*
5400 - 21.75*
5600 - 21.75*
5800 - 21.75*
6000 - 23.75*
6200 - 23.00*
6400 - 23.00*
6600 - 23.00*
6800 - 23.00*
7000 - 23.00*
7200 - 23.00*
7400 - 23.00*
7600 - 23.00*
8500 - 23.00*

Values are from a 94 manual ECU ROM file.

Dave
 
Last edited:
It's really great to see some of the older members chime in! I haven't heard from many of you folks in a while. Very useful info on this thread. Thank you

I actually upgraded to a full standalone HKS F-Con VPro Version 3.3 (the last of the Vpros) on my 3.0L OBD1 and i'm glad I did since overall driveability is significantly improved. Even just starting the car takes 1 crank and idle is smooth as can be and off/on throttle behavior is very linear. These were the things that really started to annoy me on the piggyback. The car has never behaved this well on the stock ECU even with the Comptech stock CTSC fueling solution or the HKS Piggyback but it was "safe" under boost. So once I work out all these other issues I hope to never touch this thing again!

I've spend the last few days troubleshooting the issues on my car. One of them is my inconsistent boost readings (up to 8-9psi on my 7psi pulley WTF?) and near 90% duty cycle on my RDX injectors. They weren't that high on my standalone. Fuel pressure seems solid at 54-56psi at full boost on the old school "Supra Denso" pump but the car leans out in the last 300rpm before redline. I also noticed my VTEC solenoids aren't being triggered (good one Dave!) but they were on while on the dyno. So unfortunately, something is really wacky. I started logging voltage if in case my Prelude alternator or Oddysey battery are starting to die out. Voltage seems to be at 12-12.5 nearing redline.

I'm also going to dust off my Zietronix logging software and run them in parallel to see if perhaps i'm having some faulty HKS sensor issues.

SIGH........................... Now it's Valentines day wknd and I won't get back to my car for another week or so.

- - - Updated - - -

Here's a cellphone pic of the sensor log readings at 7800 rpm on a 3rd gear pull. I can only show 6 readings at a time but I should have displayed timing also. I don't want to do another pull until I sort out these issues though. I can get a lot more granular log readings on the laptop software which i'll try to screen shot in the future.

9psi of boost??? WTF? haha I mean.. i'm not spraying THAT much water at all.

IMG_20150209_222143_zpsv00osndo.jpg
 
Last edited:
jwmelvin said:
I see those are from sr5guy's TunerPro files. Any thoughts on how they might change for the C32B?
Click to expand...

We have no idea on a 3.2l stock tune YET!, but since the piston design, valve and head design are all very similar you may see a 1-2* difference in overall timing variance, but you can have that in two of the same motors. I have hours of logs logging the live data from my OBD2 OEM ECU and the Ignition numbers are very very similar to the OBDI numbers.

I am moving forward where Matt stopped due to time constraints, I should have a boosted NSX on the OEM ECU soon for round two of testing. I am planning to build a single map that will be good for upto 15PSI of boost that can be burned to a chip and if you installed with the approved supporting mods should require no additional tuning to be safe and drivable. Custom tunes for peak power will be addressed via remote tuning and shipping custom tuned chips or in-house on my Dyno. This will be the least cost solution for a CTSC guy to get the best possible tuned solution using the OEM hardware. I am thinking a CTSC conversion kit for 6lb setups would look like this.

The Kit will include -
socket kit, chip, 550cc injectors, MAP Sensor, FPR, fuel pump.

Instructions for installation and fuel pressure settings (stock will be the target so the OEM fuel pressure regulator could be used) will be included.

I have two test CTSC cars to work out the details on so should be no real issue other than time. I wish I had more time. I really need more time.

Dave

- - - Updated - - -

RYU said:
It's really great to see some of the older members chime in!
Click to expand...

You calling me OLD!
 
Came across an interesting article today about how BMW is cooling their turbo M4. Looks like their using water injection also! This might partially explain the increase in available timing advance in my setup.

http://www.autoblog.com/2015/02/13/bmw-reveals-m4-safety-car-with-innovating-water-injection-system/

<div style='text-align:center'><script type='text/javascript' src='http://pshared.5min.com/Scripts/PlayerSeed.js?sid=281&width=480&height=401&playList=518649896'></script><br/></div>

BMW insists actually aids in the combustion process.

The idea is that the temperature of the air being mixed with the fuel inside the engine is usually hotter than ideal, so the system injects a fine mist of water into the collector in order to reduce the air's temperature... sort of like one of those hydrating misters at an amusement park or outdoor mall, but in an even hotter environment. The system brings the temperature of the air down to a more optimal temperature, helping it combust better.

The process is said to yield a number of positive effects. For one, it reduces knocking. For another, it can make more out of lower-octane fuel where higher octane isn't available. It also can control the adverse effects of higher ambient temperature on the combustion process. But most of all, it increases output and reduce fuel consumption by around eight percent.

Whether that eight percent is worth the added weight of the system – particularly with water pump and a 1.3-gallon tank in the trunk – is up for debate. But we'd imagine that the Bavarian engineers have weighed very carefully. Of course there's also the matter of refilling the water tank, which BMW says would be carried out whenever the safety car is refueled, but in real-world conditions would only necessitate attention once every five top-ups at the gas station.

By now you might have guessed that BMW probably didn't develop this system just for the MotoGP safety car, and isn't planning on keeping it confined to the racetrack. Instead it's being tested and demonstrated on the safety car before being rolled out on production models in the future. Since the manufacturer says it can optimize the system for performance or for economy, we wouldn't expect it to be implemented only on performance models, either.
Click to expand...
 
Last edited:
doc_tai said:
Have u sync ignition timming on ur hks fcon?
Click to expand...

Great point! That's one of the first things you should do when installing an aftermarket ECU... sync it to timing and TPS.

I use this and it works great:
http://www.summitracing.com/parts/ino-3568/overview/

One thing to note is that if you use the ATI crank pulley, I've noticed that the sticker for the timing is shifted by 1-2 degrees :rolleyes: So that is also something to take into account.

Dave

- - - Updated - - -

Regan,

Before your car heatsoaks on the dyno, did your tuner do a pull without water injection?
 
RYU said:
So where are you guys at? I know Cody on his turbo setups like a decent amount of timing. Our crappy California gas can't support too much but i'd love to know approx where everyone is ending up.
Click to expand...

I need to clarify this; I do not "like" any specific timing amount. I tune each car to their own respective peak power efficiency, and then back down the timing from there, for longevity. Most "stock" motors are safe and happy with 1deg per psi of boost retard.
 
RYU said:
Fuel pressure seems solid at 54-56psi at full boost on the old school "Supra Denso" pump but the car leans out in the last 300rpm before redline. I also noticed my VTEC solenoids aren't being triggered (good one Dave!) but they were on while on the dyno. So unfortunately, something is really wacky. I started logging voltage if in case my Prelude alternator or Oddysey battery are starting to die out. Voltage seems to be at 12-12.5 nearing redline.

I'm also going to dust off my Zietronix logging software and run them in parallel to see if perhaps i'm having some faulty HKS sensor issues.
Click to expand...

Did you find out why your engine leans out at high RPM's??
I would assume that with the Denso pump and bigger injectors (which ones?), correct fuel supply should not be a problem.
 

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