[TakeOne]

Off topic: but since there is a lot of activity on this thread, i feel like this question might get answered this time around.

Has anyone been able to figure out/explain why BMW increases boost when it gets hot and cuts boost down when it gets cold, in stock form?
Always seemed to be kind of backwards to me?

[InCityPhoto]

Originally Posted by Dmacc

The weakness to the timing control of the factory DME is that it is only meant to handle the stock boost pressure...

doubling the boost and relying on the stock curve is NOT the right way to tune for double the psi.

Do you want Clap to explain another 100 times?

let me dumb it down for you and everyone else who is confused

Factory timing ≠ Good for double boost pressure

want to rely on it? stick with stock boost pressure

Factory timing seems to work ok with the 1000's of other JB users that are not running 15+ PSI

[Mike@N54Tuning.com]

Originally Posted by Joshboody

what are you saying these's a difference in faking the load target compared to scaling it, as I imagine the JB does? No difference the load the DME sees is still way below actual, giving a much higher timing map then required.

Right, a big difference. If you fake the signal back it will always be perfectly smooth as the target is always perfectly smooth. If you scale it but let it wiggle as boost/throttle position wiggle, then advance will wiggle with it. But the advance values will be better mapped. I believe with their setup to compensate they do large CPS offsets during spool up and shifts. To be perfectly honest I have a hard time reading the PROcede advance charts people post. They are always 1" high from 0-30 degrees, and I never know if its actual advance, including a CPS offset, if so how much, etc.

Mike

[Focus]

Originally Posted by M335i Oreo Package

but the very first post on this thread showed a completely stock car on stock tune.... Which again brings me back to the radiator over heating theory the car was overheating so the dme pulled timing no knock could it be that bcuz the temps were so high it was pulling timing but was trying to go back and find a happy medium? Forgive me if this was stated already most of the reading was done at 1Or2 am while in a zone...lol

Maybe clap can answer this i cant.

Clap, could you possibly answer my question?

My question. If Dinan doesnt see a need to alter the ECU's safety paramaters when running their stage 3 ( Timing, etc.. ), and BMW will still back your warranty if your DINAN tuned, then why should a JBtune alter stock timing? Is it a piggy vs flash difference, although i wouldnt think so.

[chili36]

Originally Posted by Dmacc

The weakness to the timing control of the factory DME is that it is only meant to handle the stock boost pressure...

doubling the boost and relying on the stock curve is NOT the right way to tune for double the psi.

Do you want Clap to explain another 100 times?

let me dumb it down for you and everyone else who is confused

Factory timing ≠ Good for double boost pressure

want to rely on it? stick with stock boost pressure

A little more respect there kid. No need to "dumb Down" anything.
Can you prove the DME is not capable of adjusting timing with higher boost?

[Dmacc]

Originally Posted by InCityPhoto

Factory timing seems to work ok with the 1000's of other JB users that are not running 15+ PSI

In what sense do you want to talk here?

Long term effects? or short term?

These knock events are adding up, they don't just simply disappear after they happen.

If you want to talk short term, then yes, nothing noticeable is happening right now for them.

somewhere down the line? their engine will fail sooner than that of someone running either the stock tune or a tune that is able to control these knock events (or significantly reduce them).

is that clear enough for you?

[fisherbln]

Originally Posted by InCityPhoto

Factory timing seems to work ok with the 1000's of other JB users that are not running 15+ PSI

No, it isn't. Even Mike will say that the factory curve "adapts" when the ECU "learns" that it is knocking (or whatever you want to call those timing dips) at the factory timing levels.

[MDORPHN]

Originally Posted by Focus

Maybe clap can answer this i cant.

Clap, could you possibly answer my question?

My question. If Dinan doesnt see a need to alter the ECU's safety paramaters when running their stage 3 ( Timing, etc.. ), and BMW will still back your warranty if your DINAN tuned, then why should a JBtune alter stock timing? Is it a piggy vs flash difference, although i wouldnt think so.

Slightly OT, but be aware that BMW doesn't back the warranty, Dinan does.

Neil

[secretsquirrel]

Originally Posted by Focus

.... and BMW will still back your warranty if your DINAN tuned, then why should a JBtune alter stock timing?

Correction: Dinan pays for warranty claims, not BMW.

[Dmacc]

Originally Posted by chili36

A little more respect there kid. No need to "dumb Down" anything.
Can you prove the DME is not capable of adjusting timing with higher boost?

I didn't mean any disrespect, some people in previous posts asked for it to be dumbed down.

the proof that the dme isn't capable is in the logs. for example

JB tuned logs in ideal conditions, knock is occuring if not multiple times

stock logs in bad conditions conditions, less knock, however, still is occuring.

for those two examples, the tuned knock is worse, the pressure is higher in the cylinders.

for the stock knock, not as worse.

The DME can control timing decently well for stock boost pressure.

The DME CANNOT control timing as well for higher boost pressure

this problem is due to the stock timing curve it is trying to maintain...

[Jeff@TopGearSolutions]

Originally Posted by InCityPhoto

Factory timing seems to work ok with the 1000's of other JB users that are not running 15+ PSI

Maybe if a couple dozen more people tell you "NO, you are wrong", you will listen. (Ideally, you will stop posting misinformation).

Factoring timing set points are not achieved on any JB car, any map, period. (that goes for any car with increased boost).

[fisherbln]

Originally Posted by JPSlick

Factoring timing set points are not achieved on any JB car, any map, period. (that goes for any car with increased boost).

That also are not running meth or race gas.

[Joshboody]

some tuned logs from the other thread. notice the timing curve looks better than stock at higher boost. there's twice as many logs to view here for comparison
http://www.e90post.com/forums/showpo...77&postcount=1

[chili36]

Originally Posted by Dmacc

I didn't mean any disrespect, some people in previous posts asked for it to be dumbed down.

the proof that the dme isn't capable is in the logs. for example

JB tuned logs in ideal conditions, knock is occuring if not multiple times

stock logs in bad conditions conditions, less knock, however, still is occuring.

for those two examples, the tuned knock is worse, the pressure is higher in the cylinders.

for the stock knock, not as worse.

The DME can control timing decently well for stock boost pressure.

The DME CANNOT control timing as well for higher boost pressure

this problem is due to the stock timing curve it is trying to maintain...

S0 ~3deg drops are detonation?
DME is capable of calculations at lower boost and higher boost.
I doubt there is a limitation that would not allow it to control the timing at higher boost.

[Dmacc]

Originally Posted by chili36

S0 ~3deg drops are detonation?
DME is capable of calculations at lower boost and higher boost.
I doubt there is a limitation that would not allow it to control the timing at higher boost.

yes the DME is capable, but after it's timing tables have been reflashed!
I understand what you're trying to say here, but the fact of the matter is, the only thing getting in the way of this being true are the factory timing tables that are meant for the car to run lower boost.

I'm not against you at all, I'm on your side. The factor in the way is the stock timing tables, and the dme wanting to stick to it

[Jeff@TopGearSolutions]

Originally Posted by Clap135

Mentioned this 10 times already and everyone ignores it. If the dme had the ability to drop timing pre knock based on iats or temps or whatever.....why doesn't it drop timing when u run high OCTANE gas. The only parameter you are changing by running high OCTANE is the fuels resistance to.detonate.....everything else stays the same as before.

Having trouble with that phone keyboard and auto spell check i see

[Jeff@TopGearSolutions]

Originally Posted by fisherbln

That also are not running meth or race gas.

Correct.

[Dmacc]

As much as I don't like all the negativity in this thread, it's a very useful and helpful thread for understanding how timing works, and what knock is.

[Focus]

Originally Posted by secretsquirrel

Correction: Dinan pays for warranty claims, not BMW.

ah ok. im learning ^_^

[atlharry]

Originally Posted by Focus

Maybe clap can answer this i cant.

Clap, could you possibly answer my question?

My question. If Dinan doesnt see a need to alter the ECU's safety paramaters when running their stage 3 ( Timing, etc.. ), and BMW will still back your warranty if your DINAN tuned, then why should a JBtune alter stock timing? Is it a piggy vs flash difference, although i wouldnt think so.

I think this might also come down to how you read that letter from Steve Dinan. He says that they do not modify the stock safety LOGIC. Meaning if knock is detected, the DME will still drop timing just like stock. That does not mean they don't modify the timing tables.

Mappings and logic are different. Of course, that's just my interpretation, because to me, that wouldn't make sense.

[fisherbln]

Originally Posted by atlharry

I think this might also come down to how you read that letter from Steve Dinan. He says that they do not modify the stock safety LOGIC. Meaning if knock is detected, the DME will still drop timing just like stock. That does not mean they don't modify the timing tables.

Mappings and logic are different.

That's actually exactly how I read the letter.

[STONEY_M5]

Ok. Suppose BMW is being extremely conservative with there timing at the stock boost levels, would u be safe at higher boost levels.

And as far as raising boost in the heat and lowering it on the cold I think(not an expert) that they want to keep the rated hp in any condition so on hot air is less dense therefore more boost is required and when its cold more air bcuz it is more dense requires less boost. That would be my explanation but correct me if I'm wrong...