Gen 2 Cobb ATR discussion

[Dano]

Originally Posted by WillyH Can you please elaborate on how "too rich will cause knock"? Also, what is considered too rich? I would think that below 11 would be rich in my books. My thinking is that the more fuel you put into the cylinders, the bigger the temperature drop and the less likely there will be pre-detonation due to hot spots, but lower than 11 AFR will leave leftover fuel that is unburned and reduce power, and even richer < 10 AFR can possibly not ignite (assumption). I know that optimum AFR is around 12.5, and timing @ BTDC is ~ 25, but with having a turbo, running richer (without meth) due to the added heat, will keep things relatively cool. We have to also keep in mind that running 91 octane gas is less than ideal for running higher timing and AFR's. To be safe, I think it would be best if f-castrillo left the timing alone and reduced his AFR's to ~11.4. The reduction of timing will have a larger negative effect on power band than dropping AFR's, and the episodes of KR will be reduced. Also.......f-castrillo needs meth. From what i've read about meth, you can run crazy timing and AFR's close to 12.5. My stage 2 kit is going in sunday.

I'm not 100% sure why rich AF causes knock but would bet it has to do with proper mixing of fuel/air in the cylinder which leads to poor flame front. Plus the more fuel injected means longer IPW so you are spraying closer to the ignition event which can lead to spark blowout which can in turn register as knock.

93 no meth should be able to run 11:8

Add meth 12:2-5

91 no meth may be able to run 11:8 with reduced advance

Add meth and again sky's the limit almost.


Tappin

[f-castrillo]

Originally Posted by Dano2010 Did you know that too rich AF will actually cause knock? For me, I'd pull timing and run 11.8 AF across the board Time for WMI Also, don't know if you have performed the checks to see if the KR is real above 5.7K. Add octane or pull timing to see if it goes away. If not its false and you can change the sensor offset. To be safe, I think it would be best if f-castrillo left the timing alone and reduced his AFR's to ~11.4. The reduction of timing will have a larger negative effect on power band than dropping AFR's

I experienced the opposite: running 11.6 AFs and more timing appeared to net me less MAF g/s than the 11.8 map, even in areas of no knock. See my logs uploaded a few posts back.

Still, if you can elaborate on this further, ill consider re-tuning for 11.4 AFs. I'm working on my 11.8 AF map, and if that ends up being a bust, ill tune for 11.4


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[WillyH]

Originally Posted by f-castrillo I experienced the opposite: running 11.6 AFs and more timing appeared to net me less MAF g/s than the 11.8 map, even in areas of no knock. See my logs uploaded a few posts back. Still, if you can elaborate on this further, ill consider re-tuning for 11.4 AFs. I'm working on my 11.8 AF map, and if that ends up being a bust, ill tune for 11.4 Sent from my Thunderbolt (Tapatalk)

It's just from tuning my car + from what i've read on many documents and forums.

For sure though, I would consider meth and then you will have your knock issues pretty much gone + there will be a lot more room for increased power from higher timing and AFR's. It's really good stuff especially for us guys with shitty 91 gas.

[f-castrillo]

Originally Posted by WillyH It's just from tuning my car + from what i've read on many documents and forums. For sure though, I would consider meth and then you will have your knock issues pretty much gone + there will be a lot more room for increased power from higher timing and AFR's. It's really good stuff especially for us guys with shitty 91 gas.

The only reason I haven't really considered WMI is because it's one more thing that I would be paying for on a regular basis, and one more thing I had to worry about filling up. I can always reconsider

How much more MAF g/s are you flowing with meth injection, and how often do you have to refill your meth reservoir under relatively normal driving conditions (with the occasional spirited run)?

[Dano]

the difference between running WMI and not is like keeping your car or buying another one with an additional cylinder LOL

night and day,

WMI both cools the air charge and cleans the valves. What does this allow you to do??

lemme tell you.

run the K04 further out the RPM range at full boost
run more timing
run leaner AF

For the 91 oct guys the gains are multiplied.

All the above can be done safely and doesn't even require a "ragged edge" tune. My tune is setup so that if WMI quits spraying the ECU will detect KR and richen up the mixture and protect the motor.

now you can tune for the ragged edge so that if WMI were to fail so would your motor but that kinda tune isn't necessary to see the full benefits of WMI.

I run 100% meth, have a 1 gallon tank, DO7 nozzle and with normal driving I may fill the tank up once a month. When tuning and doing multiple WOT runs, I can get about 10-12 runs on a tank.

WMI is WIN

[WillyH]

Originally Posted by f-castrillo The only reason I haven't really considered WMI is because it's one more thing that I would be paying for on a regular basis, and one more thing I had to worry about filling up. I can always reconsider How much more MAF g/s are you flowing with meth injection, and how often do you have to refill your meth reservoir under relatively normal driving conditions (with the occasional spirited run)?

The thing is, the amount of time you are spending on trying to get rid of knock and manipulating the different tables, you could have installed a meth kit and be running a really stable tune without any knock and with a lot more power.

91 gas is garbage, and that's why I decided to go with the meth kit. I know that without it, the knock that I am getting will only go away with a massive reduction in power.......not what i'm looking for. I will be buying a Garrett GTX3071R Dual Ball Bearing Turbo next year, but without meth, that would be a fatal move for my engine. With meth, my target power goals of 350 whp and 400wtq will become a reality.

The cost of running meth isn't as high as you think unless you are on the track every day. For occasional spirit driving, I would assume that you would be spending maybe $10/week, which isn't that much.

I am just about to install my kit - wish me luck!

[mrmonk7663]

You can order windshield wiper fluid, the blue ones, from colder areas up north that have a meth concentration of over 30%. The brand is PEAK. If i'm not mistaken it was the one rated to -20 degrees. The -30 will not work, and the 0 degree to +20 you find in the south isn't concentrated enough to dick with. You can increase the meth concentration by buying "HEAT" from walmart (pure methanol) I would do this for a 50/50 meth to water ratio for about $5 per gallon.

[f-castrillo]

Thanks for the replies guys, you all are slowly swooning me over into buying meth lol.

I guess ill start researching WMI setups haha.

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[Dano]

Originally Posted by mrmonk7663 You can order windshield wiper fluid, the blue ones, from colder areas up north that have a meth concentration of over 30%. The brand is PEAK. If i'm not mistaken it was the one rated to -20 degrees. The -30 will not work, and the 0 degree to +20 you find in the south isn't concentrated enough to dick with. You can increase the meth concentration by buying "HEAT" from walmart (pure methanol) I would do this for a 50/50 meth to water ratio for about $5 per gallon.

some say the blue coloring will clog your meth nozzle but I can't say that from experience. The cheapest way to buy meth is from a speed shop if it's available in your area. around here I can VP M1 for 4.25 a gallon. Heet comes out to something like 8 a gallon LOL.

I'd probably ask around to see if meth is available in your area. I buy it 5 gallons at a time so even if you have to drive 20 minutes or so it would be well worth it.

anything is better than nothing

[f-castrillo]

Originally Posted by Dano2010 some say the blue coloring will clog your meth nozzle but I can't say that from experience. The cheapest way to buy meth is from a speed shop if it's available in your area. around here I can VP M1 for 4.25 a gallon. Heet comes out to something like 8 a gallon LOL. I'd probably ask around to see if meth is available in your area. I buy it 5 gallons at a time so even if you have to drive 20 minutes or so it would be well worth it. anything is better than nothing

I scoured the internets some, and found that there is a race shop here that carries methanol. I've shot off an email to them to see what brand they carry and what they charge for it per gallon.

I'm sending you a PM, by the way, regarding your meth setup. Damn you guys for convincing me to do this, and damn the mod bug lol.

[Bucker]

Another "First Log" post

[Teal]

I made some changes to my current map this week and have made a couple pulls. I was running 11.6AFR and I just moved it to 11.8AFR. Besides that, I also made some slight timing adjustments, however these arn't a knock problem at all right now so I know I have some room to play with still.

Anyway - my logs from the other day were taken right after I flashed the map and driving a few minutes. The AFR was around 11.6:1 with a few points where it dropped below one point lower than normal (more than 0.12 away from target)...

Here is a log from this morning (cooler air than when MAF was cal'd). My AFR tapers down at 6k but until then should be 11.8. I see some little fluctuations that I've never had before. It's not bad, however the car was running much more consistant when it was still 11.6.... I am having trouble hitting and holding this AFR.

Any suggestions? Should I do yet another MAF calibration? Or does my slightly advanced timing have an effect on AFR-out?

EDIT: I'm also adding a log from yesterday which was right after I flashed the map - here is is clear that then AFR is not meeting its 11.8:1 target.

[Teal]

Originally Posted by f-castrillo ...How much more MAF g/s are you flowing with meth injection...

I also meant to ask. How do you increase your mass air flow by increasing your ignition timing (or leaning your mixture, etc)? I know this quote mentions meth but I heard it mentioned also when talking only about advanced ignition timing.

MAF = mass AIR flow in gram/sec .... the cam timing is not changing so starting the ignition sooner can increase air flow how? The ignition is only effective around the compression/combustion stroke where the valves are closed....

[Ziggo]

Tuning timing based on MAF flow is certainly not ideal, but you can see subtle changes because earlier spark reduces the pressure/temperature in the exhaust manifold resulting in slightly better VE since you won't get as much blowback in the valve overlap.


---
- Zigatapatalka

[Dano]

and to further that benefit...retard your VVT to 0 as soon as possible so you are not getting cylinder blow through to the EM causing more back pressure...which reduces VE.

once the turbo is fully spooled you can crank back on VVT. Cobb is now doing this in the BTv102 maps. IIRC they go to zero at 5-5.5k

so VVT advance opens the intake valve before the exhaust valve is closed so the pressure in the IM flows through the cylinder and into the EM which enhances cylinder emptying and decreases spool time due to the volume increase in the EM. Once the turbo is spooled its time to close the chit down and build more g/s.

[Ziggo]

I am actually going to experiment with the VVT a bit on the BNR. VVT is a benefit as long as the IM pressure is over the exhaust manifold pressure, which depends on a number of factors, but generally the larger and more efficiently the turbo is running, the more VVT you can get away with. On the K04 @ 20psi, I would go to zero no later than 4.5k RPM

[Dano]

Exactly

I need to put my VVT thread together

Net is, it is very important to match VVT to your turbos spool characteristics.

I'd bet the s3 BNR is very similar to a gt2871.

VVT needs to go a bit further than 4.5k on the 28. I go to 5 k then zero.

EM makes a difference as does hotside AR but it's fun to play with.


I'll post up my tbls soon.


I haz been playing w this for some time.


Tappin

[Ziggo]

Share!

The BNR S3 is a 2871, only functional difference is the BNR is a journal and the ATP is a ball bearing.

[f-castrillo]

Please do share, they're pretty much the only tables in ATR (besides the MAP tables) that I don't understand enough to modify.

[f-castrillo]

Have you guys found self-tuning on a dyno beneficial at all? There's a few local places that run ~$125 per hour of time on the dyno. I imagine with a laptop handy, that might be enough time for an experienced tuner to push out a pretty good map. This would also solve the problem of not having good roads to datalog on. The only problem is that $125 is a lot of moohlahs...

[phate]

Yeah, dude. That's probably the easiest and most efficient way for anyone to tune a car if they know what they're doing. It's much easier to quantify gains and see what works, and lessen the risk of going nuclear because of adding too much timing or whatever.

[f-castrillo]

I'll probably rent a dyno once I get a meth kit onto the car. But I think I'm where I want to be on my current hardware setup

Sent from my Thunderbolt (Tapatalk)

[fywdyl]

I think my tune is finalized. I'm hitting my targets and my boost curve is nice a smooth. Little to no knock during WOT.

I'm trying to limit the power in 1st and 2nd now. I tried using the APP translation tables, but they don't work at all.

Bluestreak suggested that I lower the TRL tables for 1st and 2nd, but it doesn't seem to work for me (btw, I'm boost tuning). Has anyone been successful in limiting power in 1st and 2nd w/ boost tuning?

[f-castrillo]

Originally Posted by fywdyl I think my tune is finalized. I'm hitting my targets and my boost curve is nice a smooth. Little to no knock during WOT. I'm trying to limit the power in 1st and 2nd now. I tried using the APP translation tables, but they don't work at all. Bluestreak suggested that I lower the TRL tables for 1st and 2nd, but it doesn't seem to work for me (btw, I'm boost tuning). Has anyone been successful in limiting power in 1st and 2nd w/ boost tuning?

I've had better success with altering the Boost Comp 1st-2nd Gear table, but then again, I haven't done extensive testing with the TRL 1st/2nd gear tables. Also, my guess is that changing the TRL 1st/2nd gear tables wouldn't have a huge effect if you're WG Duty Load Error Comp table was zeroed out.

[Dano]

APP translation does indeed work perfectly.

TRL will do nothing if you have correctly setup BT logic as LD and Load comp tables should be zeroed.

[fywdyl]

Originally Posted by Dano2010 APP translation does indeed work perfectly. TRL will do nothing if you have correctly setup BT logic as LD and Load comp tables should be zeroed.

I am speculating that APP translation does not work for Genpus because the AP does not support Accel. Pedal Pos. as one of the logged parameters. We do have a Throttle Duty Desired - (%) that Gen1s don't have, but there isn't a table in ATR where you can modify this.

[Dano]

interesting...I must say I haven't done anything with APP Trans on a Gen2.

[mrmonk7663]

In the OTS Beta maps the VVT is turned off at 5000rpms and above, but everytime I log I get small intake valve openings intermittently after 5000rpms, and they always seem to have an effect on AFR. Anyone know why this is?

[atvfreek]

Originally Posted by fywdyl I think my tune is finalized. I'm hitting my targets and my boost curve is nice a smooth. Little to no knock during WOT. I'm trying to limit the power in 1st and 2nd now. I tried using the APP translation tables, but they don't work at all. Bluestreak suggested that I lower the TRL tables for 1st and 2nd, but it doesn't seem to work for me (btw, I'm boost tuning). Has anyone been successful in limiting power in 1st and 2nd w/ boost tuning?

The trl per gear tables will work if you give the load dynamics table a little authority. As long as you have all of your other gears trl tables out of reach (2.3 or higher) you should have no problem doing this.

My car, even with the load dynamics table zeroed out, I have boost limited when load hits 2.3 on cold mornings. So I still think no matter what you do on a gen2, (BT enabled) the load tables play a role.

[Bucker]

Originally Posted by atvfreek The trl per gear tables will work if you give the load dynamics table a little authority. As long as you have all of your other gears trl tables out of reach (2.3 or higher) you should have no problem doing this. My car, even with the load dynamics table zeroed out, I have boost limited when load hits 2.3 on cold mornings. So I still think no matter what you do on a gen2, (BT enabled) the load tables play a role.

The Beta ATR fixes this by letting you zero the Load Error comp WGDC table.

[BlueStreak]

Gents,

Attached is a datalog showing the effect of the TRL X Gear tables on my boost tuned Gen1. I am using the most up-to-date firmware, ATR and maps.

I am commanding a maximum of 2.2 calculated load. When calculated load goes above 2.25 (2.2 + .05 error the ECU allows), the throttle plate does indeed close off to limit boost and bring caculated load back in line.

EDIT: I haven't zeroed out the reductive portion of the load error table as I want the TRL X Gear tables to manage torque in the low to mid range.

EDIT x2: Essentially I am using the load tables to set a maximum load the engine will achieve. If calculated load undershoots the TRL X gear values, the ECU will do nothing. I guess you can say I'm running a hybrid load/boost tune.

[f-castrillo]

Originally Posted by Dano2010 Exactly I need to put my VVT thread together Net is, it is very important to match VVT to your turbos spool characteristics. I'd bet the s3 BNR is very similar to a gt2871. VVT needs to go a bit further than 4.5k on the 28. I go to 5 k then zero. EM makes a difference as does hotside AR but it's fun to play with. I'll post up my tbls soon. I haz been playing w this for some time. Tappin

This. The unknowledgable are waiting lol

[atvfreek]

@Bucker the new atr beta does not completely fix it, and i'm perfectly ok with that because like @BlueStreak I am using my load tables as a failsafe for when it gets cold. Already on cold mornings I hit 2.3 load and my throttle plate starts to close. And this is below my boost target, then when its hot I hit my target boost of 21 and its in the 2.2 ranges. All this is with load dynamics zeroed out. I have left my wddc load error comp table ots and this seems to give me the tune I want with all the failsafes in place.

Sent from my MB300 using Tapatalk

[Bucker]

Originally Posted by atvfreek @Bucker the new atr beta does not completely fix it, and i'm perfectly ok with that because like @BlueStreak I am using my load tables as a failsafe for when it gets cold. Already on cold mornings I hit 2.3 load and my throttle plate starts to close. And this is below my boost target, then when its hot I hit my target boost of 21 and its in the 2.2 ranges. All this is with load dynamics zeroed out. I have left my wddc load error comp table ots and this seems to give me the tune I want with all the failsafes in place. Sent from my MB300 using Tapatalk

Interesting. I know for a fact that when I zeroed out my Load error WGDC comp table and my Load Dynamics table there is ZERO effect from the load tables. I routinely hit 2.6+ load now and nothing steps in to adjust WGDC or throttle.

[atvfreek]

Originally Posted by Bucker Interesting. I know for a fact that when I zeroed out my Load error WGDC comp table and my Load Dynamics table there is ZERO effect from the load tables. I routinely hit 2.6+ load now and nothing steps in to adjust WGDC or throttle.

Ahhh, I guess I would have to zero out the wgdc load error comp table as well to have it not apply the load values. I have that table left at the ots values, but I'll probably keep it that way for the colder weather.

[f-castrillo]

I've been on a break from ATR, since my map is pretty much where I want it to be, but a few questions have come to mind in the last few days, now that I'm starting to look at meth kits.

1. How have you guys been handling your fueling targets? Because I've set my closed-open loop transition to happen at 1.25 load and up (as defined in the Max Load D table), I have also set my fueling targets from 1.25 load and up to 11.8:1, while interpolating vertically to the first occurence of 14.680 in the column (usually up a few rows from my 11.8 targets at early RPMs, and several rows up in high RPMs). Is this a proper strategy for the fueling tables? I haven't had any issues with my setup, but I just wanted to see if there were alternate/better strategies in cleaning up the fuel tables.

2. Do leaner fuel targets really make a difference with meth injection? I had a discussion with @BlueStreak over PM, and he told me that the dip in AFRs is just due to the onset of spraying, and that it reaches commanded AFs further up the RPM band. I'm not disputing your info, @BlueStreak, I'm just trying to paint a bigger picture for myself. I understand that WMI's big advantage comes in the form of being able to advance timing. Coming from Cali 91 octane, I presume I'll be able to advance timing by quite a bit with WMI

3. Has anybody found the need to alter the VVT table on the stock K04? Stock parts vs. full bolt-ons? I ask because I'm more or less fully bolted (cat-back aside, but supposedly that won't do much for me until I'm flowing even more g/s), still running OTS values in the VVT table, and want to know if it's worth my time to tweak the table at all, given my mods. Then comes the issue of not knowing how to change the table values lol

4. I haven't messed with the APP translation tables at all. Have any fully bolted Genpu guys found decent 1st and 2nd gear values that deliver power right up to the point of pre-wheelspin? I guess I could teach myself some driver mod, or get some stickier tires. I just want some insight on what good baseline values may be.

[BlueStreak]

Originally Posted by f-castrillo I've been on a break from ATR, since my map is pretty much where I want it to be, but a few questions have come to mind in the last few days, now that I'm starting to look at meth kits. 1. How have you guys been handling your fueling targets? Because I've set my closed-open loop transition to happen at 1.25 load and up (as defined in the Max Load D table), I have also set my fueling targets from 1.25 load and up to 11.8:1, while interpolating vertically to the first occurence of 14.680 in the column (usually up a few rows from my 11.8 targets at early RPMs, and several rows up in high RPMs). Is this a proper strategy for the fueling tables? I haven't had any issues with my setup, but I just wanted to see if there were alternate/better strategies in cleaning up the fuel tables. 2. Do leaner fuel targets really make a difference with meth injection? I had a discussion with @BlueStreak over PM, and he told me that the dip in AFRs is just due to the onset of spraying, and that it reaches commanded AFs further up the RPM band. I'm not disputing your info, @BlueStreak, I'm just trying to paint a bigger picture for myself. I understand that WMI's big advantage comes in the form of being able to advance timing. Coming from Cali 91 octane, I presume I'll be able to advance timing by quite a bit with WMI 3. Has anybody found the need to alter the VVT table on the stock K04? Stock parts vs. full bolt-ons? I ask because I'm more or less fully bolted (cat-back aside, but supposedly that won't do much for me until I'm flowing even more g/s), still running OTS values in the VVT table, and want to know if it's worth my time to tweak the table at all, given my mods. Then comes the issue of not knowing how to change the table values lol 4. I haven't messed with the APP translation tables at all. Have any fully bolted Genpu guys found decent 1st and 2nd gear values that deliver power right up to the point of pre-wheelspin? I guess I could teach myself some driver mod, or get some stickier tires. I just want some insight on what good baseline values may be.

1. Yes.

2. There's a caveat here. Assuming you are spraying enough meth to make a difference in AFRs up until redline, you CAN pull commanded fuel and effectively lean out the mixture down to a desired ratio (or just lean it out anyways if your setup doesn't richen AFRs -> you can do anything you want, really...). If, in addition, you decide to add timing, you can make more power BUT if meth stops working for whatever reason, you have the danger of blowing your engine from 1) the additional timing that you couldn't run without meth AND 2) the leaner fuel targets you changed to compensate for the extra meth flow. If you do both and meth stops, you'll be searching for a new block :-)

Now, @Dano2010 has a nice approach where he doesn't lean out his commanded fuel but only adds timing. Should meth stop, there is enough "safety" built into the tune that the ECU will only have to rely on pulling 1-2 degrees timing to prevent the engine from knocking (of course, it will also add fuel). I believe he also only adds 1-2 degrees of timing more than his non-meth tune as an added safety to not changing targeted AFRs. I'm with Dano here and I choose not to touch fueling. Even so, I run 3-4 degrees more timing than my non meth tune so I'm pretty sure my engine will get hurt if the meth setup ever goes south during a pull.

3 and 4. Others can chime in.

[fywdyl]

4. APP doesn't work for Genpus. I'm going to use @BlueStreak recommendation of using 1st and 2nd TRL tables with the WG Load Error Comp (the right hand side only). Haven't had a chance to test it yet, but I'll post logs once I get a chance.

[rfinkle2]

@f-castrillo...

1)I assume we are talking about the same thing, but all of my fueling tables are 100% the same (with the exception of the max enrichment table)

I found it best to use one of the larger open loop tables to start, adjust my fueling to coincide with my wot targets @ a particular load, and copy and paste that table to every table. (note the closed loop and closed throttle table contain 2-3 extra lines of load that need changing when copying and pasting).

2) All of the info that I read on meth tuning (@ least from the manufacturers recommend tuning with meth off to 12.0 - 12.5 afr, with very conservative timing). Once you turn the meth on, find a combination of nozzle, mixture and pump pressure to see a .5 point drop in afr's).. add boost and timing back in. If you use a meth failsafe / and or tweak your tune for use of the high bat flag, that would add some safety in addition to the above strategies.

[BlueStreak]

Rob, I'm thinking a .5 drop in AFR is really tough to maintain unless you're spraying a whole lot of meth (close to 100% mixture and a large nozzle). I have yet to achieve that, at least. Here's some empirical evidence:

Pull 1
Meth Mix: 75% Meth/25% Distilled Water
Flow: 12GPH (D12 nozzle equivalent) - Direct Port
Note: BATs do not change due to direct port setup.
Controller: MAP Based. Start spray at 5PSI - Full spray at 20PSI.
Targeted AFRs: 11.8

If you look at AFRs, the measurable effects disappear by ~5500RPM (ignore the richer blip just after 5500RPM, that was due to the .35 KR -> I didn't upgrade my AP at his point for faster logging). By redline, there is no difference in AFR.

Pull 2
Meth Mix: Blue WWF. 30-40% meth.
Flow: 12GPH (D12 nozzle equivalent) - Direct Port
Note: BATs do not change due to direct port setup.
Controller: MAP Based. Start spray at 5PSI - Full spray at 20PSI.
Targeted AFRs: 11.8

With this setup (less meth concentration), the effects on AFRs disappears by ~3800RPMs.

This does prove that higher meth concentrations make a more pronounced and prolonged effect on AFRs. With 100% meth, I'm sure the effects will be even greater. Still though, .5 richer to redline will be tough IMO.