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General Attention High Compression E85 Users-Ignition timing questions

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I haven't seen an AFC in over 15 years just for the record if you look at my profile you'll see my car is anything but stock 522 horse 468 pound-feet of torque open tuning on E85 for years not saying that this is the only method and way to go just saying I found truth to it in my tuning and data logging

I have a stand-alone knock sensing system to J&S safeguard in which I can dial in its sensitivity and my engine lights for more timing being run at 12 12.5:1 then it does in the range of 10 to 1.

My current time in tables start out at 11 degrees at 30 PSI and Peak torque and advanced to 17 degrees by 8500 RPM at the same boost levels
 
That is not what I said at all. You have to be realistic in the actual mass flow(what i meant to say) potential of what you are working with and what is a realistic output of said unit. I have not used or datalogged any sort of airflow numbers other than manifold pressure in years. It does you no good. Every car I get my hands on we are trying to max the turbo out. No matter the size. It is just commical that Mitsubishi guys still live and die by what a now extinct datalogger uses as a calculation(not actual data used by the ecu) in the equation.

If you want to really know what is going on either monitor your air metering system in hz (frequency) or that particular sensors scaled voltage. That will tell you more about what is going on and if you have more to gain. I only use this info occasionally on more stockish, street based cars with an actual air flow sensor. A speed density car I generally know what is to be expected based on the compressor inducer. That does not work for everyone as not everyone has been wasting the past 18 years of their life with these cars like I have.
 
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If you are tuning a gm car, or car with a gm maf the hz output is a mass flow reading that can be directly converted to lbs/min. Any measure of actual mass flow is reading the same exact parameter as lbs/min and only needs a conversion to be a lbs/min unit.

Any actual measure, or calculation of mass flow is lbs/min.
 
Again, I do not use any airflow numbers. I keep a simple method to it.

XX millimeters =xxxx horsepower

X turbo should equal Y horsepower.

I will repeat, this is a Mitsubishi thing. Any other turbo car I have been a part of has no use or care for lbs/min or airflow.

If you flow 80lbs/min of real, actual air it just means you have a well put together car. If your car weighs 4000lbs, has street tires and has a horrible powerband you are going to have a slow car. Not everyone races a datalog or a dyno sheet. Some of us prefer an actual time slip versus a theoretical number that only impresses people looking at a computer screen or their phone. Some of us have track only cars that we take serious, while others have respectable street cars that they just want to run well.

Back on point. Turn it up until it stops going faster. Probably near there anyway given how small the turbo is and your baby hotside. I hope you did not waste all that time and effort decreasing your tuning window just to go slower. That would certainly make me upset.
 
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I haven't seen an AFC in over 15 years just for the record if you look at my profile you'll see my car is anything but stock 522 horse 468 pound-feet of torque open tuning on E85 for years not saying that this is the only method and way to go just saying I found truth to it in my tuning and data logging

I have a stand-alone knock sensing system to J&S safeguard in which I can dial in its sensitivity and my engine lights for more timing being run at 12 12.5:1 then it does in the range of 10 to 1.

My current time in tables start out at 11 degrees at 30 PSI and Peak torque and advanced to 17 degrees by 8500 RPM at the same boost levels

I wasn't referring to you with my analogy. I know your car is built. My point was, in my experience, when a noob wants those mods, most anyone can tell them what to expect based on a healthy stock motor. When you start building motors, changing cams, turbos, etc, things change and you may get results that others would not have expected. I.E. my car seeming to run better now with 9.5-10 afr's instead of the traditional 12 =/- half a point that so many e85 users seem to run with, (including myself in the past).

Again, I do not use any airflow numbers. I keep a simple method to it.

XX millimeters =xxxx horsepower

X turbo should equal Y horsepower.

I will repeat, this is a Mitsubishi thing. Any other turbo car I have been a part of has no use or care for lbs/min or airflow.

If you flow 80lbs/min of real, actual air it just means you have a well put together car. If your car weighs 4000lbs, has street tires and has a horrible powerband you are going to have a slow car. Not everyone races a datalog or a dyno sheet. Some of us prefer an actual time slip versus a theoretical number that only impresses people looking at a computer screen or their phone. Some of us have track only cars that we take serious, while others have respectable street cars that they just want to run well.

Back on point. Turn it up until it stops going faster. Probably near there anyway given how small the turbo is and your baby hotside. I hope you did not waste all that time and effort decreasing your tuning window just to go slower. That would certainly make me upset.

It is what it is. We will find out one way or another if the car is going to be slower or faster on this setup. If it's slower, then i'll just have to go with a bigger turbo. HX52 in a divided 16cm housing or BW S364.5 with the 68mm turbine in a divided t4 housing are the two options I have been looking at.
 
I will repeat, this is a Mitsubishi thing. Any other turbo car I have been a part of has no use or care for lbs/min or airflow.

I don't know why you keep reiterating this in various threads. You're probably one of the few people I've ever heard of who doesn't use airflow numbers. I've literally met hundreds of people who reference airflow outside of the Mitsubishi platform. It's actually very common, contrary to what you're saying.

Not only do many people outside of the Mitsubishi platform use it, but many turbo manufacturers do as well. You have to understand why measuring airflow is useful before you can employ it effectively. What unit airflow is measured in is completely irrelevant. For Mitsubishi guys, lbs/min is most commonly used and easiest to understand, which is why it's often referenced. That fact alone doesn't make the discussion of airflow measured in lbs/min something exclusive to Mitsubishi guys...

Bottom line, airflow is just another parameter you can use to understand the performance of a particular setup. If it's available to you, you should use it, IMO. To say is does you no good to look at airflow is grossly inaccurate. There are things airflow measurement can tell you about your car's performance that boost pressure alone simply can't in most cases.
 
Man you guys are blowing this way out. I only brought in calculation of air flow as a sanity check. If he runs the numbers and it shows he's moving 100lbs/min something is wrong. Likewise if it said 30, it would be a problem as well.

We all know a 76hta at 30psi is a 50-60lb/min turbo. So if the calculations says something outside of this range, it indicates something is likely wrong. lets not get wrapped around the axle here.
 
We all know a 76hta at 30psi is a 50-60lb/min turbo. So if the calculations says something outside of this range, it indicates something is likely wrong. lets not get wrapped around the axle here.

No, we all don't know that. You have to remember some people reading this thread do/will not understand the points you just explained above, which is exactly why explaining the reasoning behind looking at airflow is important. When people express their opinions, they should be made clear so they aren't misinterpreted as facts by those who are learning.
 
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Peak airflow definitely isn't a good "picture" of a setup either.... while we're talking about it. I'd be more interested in how long a high airflow number could be held across the power band rather than peak power. Peak power is for dyno queen cars not necessarily for fast 1/4mi cars.
 
Update: Swapped in a fresh sensor. And did a pull. Nothing really changed in regards to AFR's, so my previous sensor was fine.

Anyway, here are the results based on the formula @bastarddsm had posted.

Pull 1: Kept boost the same just wanted to make sure there was still no knock. Peaked 31-32psi falling to about 28psi at 8000. Timing 11* AFR 9.55:1 52.79lbs/min, 8500rpm, 26.9psi, 13*, afr 9.84, 55.69lbs/min

Pull 2: Peak 37psi falling to 29psi by 8000. Timing 12* AFR 9.73:1 55.71lbs/min, reading at 8500 was 29psi, 13*, afr 10.49, 63.51lbs/min. Now, during the shift into 3rd, while rpms fell during the shift, afr went 10.55 and I got 6cts of knock. RPMS fall to 6300, and ecu pulled timing and knock was gone by 7000rpm. AFR 10.0. So I added some fuel from 6000rpm up to try to avoid knock registering and timing pull during the shift.

Pull 3: Peak 35-36psi falling to 31.1psi by 8000, timing 12*, afr 9.55:1 56.57lbs/min, no knock registered on the KS. (Pics attached with a fresh spark plug from this pull.) 8500rpm 13* afr 9.32:1, 58.88lbs/min. This time no knock registering on the KS during the 2-3 shift.

Pull 4, kind of: Got on the freeway, wanted to test out some brake boosting. Anyway, 2nd gear, 8000 rpm 31.1psi, 12*, 9.55:1 afr, 60.33lbs/min, shifted into 3rd peak of 35.6psi falling to 29.3psi at 8000rpm, timing 12*, afr 9.43:1, 55.85lbs/min

So increasing boost does seem to increase airflow to some extent, but i'm not turning it up any higher on this turbo with this motor.

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Still light on the timing looking at the heat register. However, if it responds to more fuel and you can turn the boost up (which you have ), keep the timing where it is at and you can get repeatable results. Being able to beat and hot lap on the car is more fun than one or two miracle pulls or having to worry about things flying apart each run.

I generally will tune the car in a single gear to get it really close. After I am confident the car is going to stay together is when i start to do 1-3 or 1-4 gear runs. After a few of those and things look good is when you can feel safe you are done. And I don't have to do much other than check things out occasionally or if problems pop up. Slow and methodical. You have done things right by not rushing the process. Scattering parts is fun for no one.

Glad to hear throwing fuel at it was all it really needed.
 
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May be running 570whp 2015 5.0 this weekend so we will see how that goes, and then the 1/4mi on the 28th if car doesn't break before then, so we will see how things go.

I am going to look into switching my crank case vent system to an open can rather than recirculated, and see if that makes any difference. I may be sucking in vapors of the crap in there and that may be hurting octane as has been previously mentioned. Routing to the exhaust system like the v8 and some supra guys do may be an option as well.
 
I ran a sealed setup and did not have issues over 800hp. Not saying on paper it won't hinder you but, I can't see it making things go to shit like they did. That is solely based on your static compression.

I have yet to experiment with it on a forced induction car but, have had great luck on a naturally aspirated car venting to the exhaust. So much so on my Samurai it was pulling so much it was just smoking like a freight train as soon as I added the vent. We took it off and there was all sorts of oil at that point in the exhaust and it stopped smoking when vented. Hooked it back up and it smoked again. So I added a second vent into the exhaust and the smoking went away. It works, maybe too good in some cases. It took two to balance out my little 1.3L engine
 
I am going to look into switching my crank case vent system to an open can rather than recirculated, and see if that makes any difference. I may be sucking in vapors of the crap in there and that may be hurting octane as has been previously mentioned. Routing to the exhaust system like the v8 and some supra guys do may be an option as well.
I did this on my car and it cured my knock issues.
I'm running a FP HTA Old School Red
Compressor wheel - Cast GT35R
Flow rating - 65LB per minute
CW Measurements - 61.5MM Inducer / 82MM Exducer
TW Measurements - 67.3MM Inducer / 58.8MM Exducer
Compressor Housing - 84MM Flow Advancement Port Cover
Turbine Housing - FP 8CM
@ 32psi with a 150-shot N2O Renegade 112.
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If I can sell this current setup, my new setup will require a custom down pipe to be made so at that point I will probably convert to the exhaust system and just completely bypass a catch can. Just let it all get burnt up post o2 sensor.
 
I did try it the way your saying "just completely bypass a catch can" but on setup pulling from the valve cover the baffle didn't work very well and dumped a ton of oil into the exhaust system, major smoke show.LOL So bought the oil catch can separator and that did the trick. I do run a open line off the VC (small hose in the first pic)to keep the vacuum down a bit from the exhaust evac.

This next spring I'm going to run a tee to the turbo oil return line and after two passes open the catch can valve and drain the oil back to the oil pan.
 
The V-8 exhaust smog pump check valve thing was tried a decade ago by several of the big names and it didnt work well due to the exhaust pressure in a turbo car vs scavenging from a n/a setup.
 
The V-8 exhaust smog pump check valve thing was tried a decade ago by several of the big names and it didnt work well due to the exhaust pressure in a turbo car vs scavenging from a n/a setup.

Why would it work for supra guys and turbo cummins then? Post turbo, how would the exhaust part be any different? Exhaust/air flowing past a properly angled tube should create a venturi effect, thus pulling air/creating vacuum for the crank case.
 
Not sure why he thinks it won't work? It works awesome on my car!!! I have seen them on 1500HP+ turbo cars working without any issues.
The best part is it helps keeping from all the gasket pushing out. Every since I installed it, my car doesn't drip a drop of oil.;)
 
Posting to see track results and updates, but I'm also wondering what biglady is seeing on the spark plug ground strap that says the ignition timing is too low. I saw the black specks indicating detonation, but I can't tell anything about the ground strap other than the coating or whatever is coming off...
 
I already stated earlier in the thread what the ideal burn range is on a spark plug. Where the heat mark indicates optimal performance. A simple Google search will validate the claim. Not my rules. The rule has been in place longer than I have been alive.
 
I already stated earlier in the thread what the ideal burn range is on a spark plug. Where the heat mark indicates optimal performance. A simple Google search will validate the claim. Not my rules. The rule has been in place longer than I have been alive.


Lol I wasn't questioning you at all, I was wondering what this heat mark is that you're seeing, for my own knowledge. The entire electrode looks the same to me, at least on this screen, so I was hoping you could circle the spot in question where this heat mark is. I understand that you want the heat mark to be right at the bend, optimally.
 
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