[BrianMN]

Originally Posted by mithiral67

Here's Robs response. He responded in 4 hours to my email.

1) We do modify the VANOS on both the exhaust and intake cams for a boost in power.
2) We don't modify the fuel injector open and close timing directly. As of now we are using BMW algorithms which are told to hit an AFR and do so by means of the injector open time. As we dig further into the fueling of the car with larger turbos we will, if need be, change when and how the injectors are opening.

That's awesome; hopefully Rob can come in here and post this as well. (Not that I don't believe you....but this is here for that reason)

Also-"modifying the Valve timing to get a boost in power" doesn't sound like something he'd say...and that statement absolutely as vague as can be. Surely, if this is true, they spent significant time testing this....and they would have data/dynos to prove it.

Not asking for the 'secrets'. Just asking for COBB to present data that is tangible and measurable...as there is none. I WANT TO BE WRONG about this; and I invite COBB to present just a small bit of data to support this.

[Bash]

Originally Posted by BrianMN

That's awesome; hopefully Rob can come in here and post this as well. (Not that I don't believe you....but this is here for that reason)

Also-"modifying the Valve timing to get a boost in power" doesn't sound like something he'd say...and that statement absolutely as vague as can be. Surely, if this is true, they spent significant time testing this....and they would have data/dynos to prove it.

Not asking for the 'secrets'. Just asking for COBB to present data that is tangible and measurable...as there is none. I WANT TO BE WRONG about this; and I invite COBB to present just a small bit of data to support this.

Off topic but are you planning to purchase the AP if they can manipulate ipw etc?

[rader1]

Originally Posted by Joshboody

I'm scared to respond, since Brian will scold me.
I was just saying similar to what Mithiral posted that Cobb is using BMW stock tables and logging map0 to map2 would be different loads so you can't determine if they changed anything. But looks like its the same pressure. Now ipw not changing is weird... did you log at WOT? % is IDC

EDIT: now let's get some map0 VANOS logs for comparison.

Yes, i logged at WOT. 3rd gear at about 3K RPM and then going WOT. I'm thinking IPW DID, change. But since it's read in % instead of time we just can't see the change. Maybe, on stage 0 it's 74% of 1.8ms(or whatever it targets) and on stage 2+ it's 74% of 2.7ms.
What i find odd is the stock rail pressure, according to a source(i'm sure many of you know what i'm talking about) stock rail pressure should be around 90bars. 2900psi is almost 200bar, i'm confused a little by this

As far as brian goes, i applaud what he's doing. But, he should've contacted Rob directly and reported his findings and then asked the forum if they had any data to add.

[BrianMN]

Originally Posted by Joshboody

I'm scared to respond, since Brian will scold me.
I was just saying similar to what Mithiral posted that Cobb is using BMW stock tables and logging map0 to map2 would be different loads so you can't determine if they changed anything. But looks like its the same pressure. Now ipw not changing is weird... did you log at WOT? % is IDC

EDIT: now let's get some map0 VANOS logs for comparison.

Haha what? Scold you? No drama in here man...bring facts to the table (as you are) and we'll be good

Originally Posted by Bash

Off topic but are you planning to purchase the AP if they can manipulate ipw etc?

I've already got it coming for my 'valentines day present'. I'm not just a guy trying to find a "gotcha" scenario.

Also- it's not a question of CAN they control/manipulate these things, because we know they can. The questions are: DO they change/tune/manipulate these things, and DOES it provide any BENEFIT? I'm betting NO, but I would LOVE to see data/proof that I am wrong. Again, not just a fanboy trying to solidify my choice (JB+ @100% FTW), I'm a customer looking for answers about the product.

Originally Posted by rader1

Yes, i logged at WOT. 3rd gear at about 3K RPM and then going WOT. I'm thinking IPW DID, change. But since it's read in % instead of time we just can't see the change. Maybe, on stage 0 it's 74% of 1.8ms(or whatever it targets) and on stage 2+ it's 74% of 2.7ms.
What i find odd is the stock rail pressure, according to a source(i'm sure many of you know what i'm talking about) stock rail pressure should be around 90bars. 2900psi is almost 200bar, i'm confused a little by this

As far as brian goes, i applaud what he's doing. But, he should've contacted Rob directly and reported his findings and then asked the forum if they had any data to add.

Actually this thread was directed towards COBB (as referenced in the title) Pretty simple. What benefit would it have if I just asked COBB via email? Now when the next 10 people want to know this specific answer; they will [hopefully] search and find this thread....which will keep COBB's inbox from filling up with repeat questions!

[Jeff@TopGearSolutions]

I know cobb mentioned they did mess with Vanos. (not helpful to the OP question).

However, I am too curious what difference on paper that is powerwise. Before and After Dyno?

[Rob@Cobb]

Originally Posted by BrianMN

That's awesome; hopefully Rob can come in here and post this as well. (Not that I don't believe you....but this is here for that reason)

Also-"modifying the Valve timing to get a boost in power" doesn't sound like something he'd say...and that statement absolutely as vague as can be. Surely, if this is true, they spent significant time testing this....and they would have data/dynos to prove it.

Not asking for the 'secrets'. Just asking for COBB to present data that is tangible and measurable...as there is none. I WANT TO BE WRONG about this; and I invite COBB to present just a small bit of data to support this.

What mithiral posted was my response since the questions were pretty simple. I do apologize for not being more descriptive.

We change VANOS for a couple of reasons. One being it is how BMW recirculates exhaust gas (EGR). Two to change the profile of the cams to add a little response and power long with smoothing transitions between tables used across different ECU modes. The changes are one of those things that make the area under the curve better as well as the response of the motor. There is nothing to hide from our side. The tunes will all be available to look at when ATP/ATR is released. ATP is out for closed beta now and ATR should follow ATPs release by a few months (maybe sooner).

I know we have some dyno plots somewhere, but I don't know when I'm going to have a chance to dig for them for posting. We're feverishly working to knock out the quirks of the stage 1 + FMIC maps to get them our ASAP.

Cheers,
Rob

[timtech]

Originally Posted by Rob@Cobb

I know we have some dyno plots somewhere, but I don't know when I'm going to have a chance to dig for them for posting. We're feverishly working to knock out the quirks of the stage 1 + FMIC maps to get them our ASAP.

Cheers,
Rob

Great to see this post. Awesome!

[BrianMN]

Originally Posted by Rob@Cobb

What mithiral posted was my response since the questions were pretty simple. I do apologize for not being more descriptive.

We change VANOS for a couple of reasons. One being it is how BMW recirculates exhaust gas (EGR). Two to change the profile of the cams to add a little response and power long with smoothing transitions between tables used across different ECU modes. The changes are one of those things that make the area under the curve better as well as the response of the motor. There is nothing to hide from our side. The tunes will all be available to look at when ATP/ATR is released. ATP is out for closed beta now and ATR should follow ATPs release by a few months (maybe sooner).

I know we have some dyno plots somewhere, but I don't know when I'm going to have a chance to dig for them for posting. We're feverishly working to knock out the quirks of the stage 1 + FMIC maps to get them our ASAP.

Cheers,
Rob

Thank you for the post! Can we discuss a bit further?

One discussion revolves around timing of both cams throughout the RPM/load range. (Power)
Another discussion revolves around overlap of cams. (Emissions)

Let's get overlap out of the way.
We should first agree on the OEM valve timing/overlap sequence. Unless this engine is different than most, this is my general understanding of valve overlap (Please correct or confirm)

-Zero overlap during cold start, idle or high load.
-Overlap induced only at moderate load.

Cold start-Both intake and exhaust valves are opened earlier, and the overlap is reduced to minimal or none. Some people/companies even believe negative valve overlap is even more beneficial warm up, as it further stabilizes the charge allowing even more retarded ignition timing...all of this results in more heat to warm up the cats, and reduce Hydrocarbons during warmup.

For normal driving, The overlap and induced internal EGR in the manifold/charge allow for better emissions and fuel economy. Increased overlap allows more exhust gas to go into the manifold/intake charge. General VVC/ overlap reactions are:

The EGR 'diluted' charge in the intake manifold has a few benefits:
- The charge will burn quite a bit slower and at a lower temp, which allows you to advance timing further and have a later peak temp, making an overall happier engine.
- The lower temp also is the cause of significantly decreased NOx and some emissions.

Contrary to popular belief, much of carbon buildup is a result of Internal EGR (valve overlap); not Oil/vapors in the intake tract sytem.

So, let's assume we don't care about hydrocarbon or NOx emissions and combustion temp. It's widely accepted that at full load zero overlap is desireable, so what can happen if you take away overlap at moderate loads? It would seem just the benefit of reduced carbon buildup would be enough of a reason to reduce any overlap.

That said; What does COBB do to change overlap at moderate load?


Now on to the power.

Not-so-long-ago it was though by many (including cobb) that BMW had a very well-designed and perfected valve timing map. It appears that you have now conducted testing with valve timing and are now claiming benefits of a 'bump' in power, increased response and smoother transitions between tables. Since there are so many variables/dependancies on the tuning of smoothness into this engine. let's focus on power and response. I realize it is nearly impossible to give objective data into the 'reponse' of the engine....so we must narrow scope to simple power.

What difference can I expect to experience with regards to OEM vs. COBB maps in the following 'under the curve' scenarios?:

-30% throttle @ 2krpm
-30% throttle @ 4krpm

-50% throttle @ 2krpm
-50% throttle @ 4krpm

Rob- Perhaps it would be easier if you describe the significant and measureable benefits that I/we will notice?

Thank you for your time,
Brian