[EJ_3]

Originally Posted by JamesM3M5

Save your money. Any tune increases the chances of problems, and problems = more money spent chasing them down. If you balk at an $800 Cobb AP, you'll pass out after seeing some maintenance bills. Brakes, tires, intake cleaning, plugs, coils, injectors, water pump/thermostat, HPFP, LPFP, etc.

Tuned or not, these maintenance items would still have to be done...

Originally Posted by sickem

You're looking for a flash tune then (Cobb, giac, renntech) as opposed to a piggyback (procede, jb4).

This.

[jippii ensio]

When temps drop, Cobb etc flash tunes decrease boost whereas piggies increase the boost. So, the basic logic of a piggy is a lot better. This can be noticed even within a day when the day is hot and night is cold.

It is also well known that the off the shelf Cobb tunes leave a lot on the table and the above logic problem is one reason for it.

A custom Cobb tune is even more dollars, but even that does not get rid of the problematic logic.

[E90Company]

Originally Posted by jippii ensio

When temps drop, Cobb etc flash tunes decrease boost whereas piggies increase the boost. So, the basic logic of a piggy is a lot better. This can be noticed even within a day when the day is hot and night is cold.

It is also well known that the off the shelf Cobb tunes leave a lot on the table and the above logic problem is one reason for it.

A custom Cobb tune is even more dollars, but even that does not get rid of the problematic logic.

That, and it's known for even COBB's stage 1 maps to be pushing 18psi regularly. Can't be good for your stock turbos, especially with stock DP's.

[GTstunna612]

Yea I think with the JB4 and map 1 you can run a safe 13psi....also u can turn the turn off and run it stock....gonna get the JB4

[Fully_Bolted]

Originally Posted by E90Company

That, and it's known for even COBB's stage 1 maps to be pushing 18psi regularly. Can't be good for your stock turbos, especially with stock DP's.

Cobbs stage 1 without an intercooler doesnt push anywhere near 18psi. The stage 1 + FMIC will briefly hit 18psi in the lower RPM's. This is within the compressor efficiency maps so im not sure why thats an issue?

[Fully_Bolted]

Originally Posted by GTstunna612

Yea I think with the JB4 and map 1 you can run a safe 13psi....also u can turn the turn off and run it stock....gonna get the JB4

Both tunes will produce similar power on stage 1.

Cobb stage 1 will run more boost and reduce timing significantly as the stock timing curve is rather aggressive. This tuning theory has been proven to make safe and repeatable power. People sometimes gawk at the amount of boost Cobb tunes run, but if you look at the overall boost curve you will notice that it runs alot of boost in the low/midrange RPM's and quickly tapers to stay withint the compressor efficiency maps for the stock turbos. This results in much more low end torque.

JB4 runs less boost but much more aggressive timing(stock timing curve). This is because the JB4 cannot directly control timing, so they are forced to run less boost.

Both tunes are good, just two different ways to go about doing things.

[Jeff@TopGearSolutions]

To correct some misunderstanding and misconceptions:

-Cobb's OTS maps are within the efficiency of the compressor maps.
-I'd be hard pressed to see 18 PSI on a Cobb stage 1 with 100% Full open throttle TPS. (Perhaps on 1+ just in the mid-range, perfectly acceptable).
-JB4 may run lower boost but it has higher ignition (there is always a happy medium to tuning).
-There is more then 1 way to kill a chicken.
- PROcede, Jb4, Cobb, and any other tune can only make so much power on an otherwise stock vehicle.
-There is no magical tune that is "faster", they all can be tweaked to optimize efficiency on a nearly stock car. (Some do it better, and/or easier, and/or different then others).

[shortseller]

A bit more on the higher cost range, the Dinan stage 2 flash offers 13 psi all day with excellent engine safety management considerations.

[GTstunna612]

my first choice was the COBB but I like the user features of the JB4. Is there any pros and cons with the COBB, PROcede, JB4?

[wahooooman]

Jb+ stage 2, Boost controller, for not fiddling with the ecu area, easy install adds some power, maybe enough for you!!!

Originally Posted by E90Company

That, and it's known for even COBB's stage 1 maps to be pushing 18psi regularly. Can't be good for your stock turbos, especially with stock DP's.

Hmm, this is interesting to me i didn't realize that running 18ish psi on stock dps would be a problem, makes sense now due to the pressure, but on my jb4 Map5 i am running 16-17-18psi ...a lot of the time, should i be concerned ? Thanks

[marv85]

Originally Posted by Jeff@topgearsolutions

To correct some misunderstanding and misconceptions:

-Cobb's OTS maps are within the efficiency of the compressor maps.
-I'd be hard pressed to see 18 PSI on a Cobb stage 1 with 100% Full open throttle TPS. (Perhaps on 1+ just in the mid-range, perfectly acceptable).
-JB4 may run lower boost but it has higher ignition (there is always a happy medium to tuning).
-There is more then 1 way to kill a chicken.
- PROcede, Jb4, Cobb, and any other tune can only make so much power on an otherwise stock vehicle.
-There is no magical tune that is "faster", they all can be tweaked to optimize efficiency on a nearly stock car. (Some do it better, and/or easier, and/or different then others).

This is the only post that makes sense in all this thread. I've read through and I'm tired of responding to silly comments about COBB boost, and JB4 being safe or the other way around...

Thanks for posting this Jeff

[marv85]

Originally Posted by jippii ensio

When temps drop, Cobb etc flash tunes decrease boost whereas piggies increase the boost. So, the basic logic of a piggy is a lot better. This can be noticed even within a day when the day is hot and night is cold.

It is also well known that the off the shelf Cobb tunes leave a lot on the table and the above logic problem is one reason for it.

A custom Cobb tune is even more dollars, but even that does not get rid of the problematic logic.

The basic logic of a piggy is not better, it's as you mentioned basic (dumb).

COBB (BMW DME logic/tuning) does not target boost. It targets load. Load can vary due to many variables. Boost being one of these variables.
The DME will try to achieve the target load with the least boost possible. When the temp drop, the car will be able to achieve the target load with less boost and hence it reduces the boost. that's not a bad thing. YOU ARE NOT LOSING POWER DUE TO THIS, YOU ARE ACTUALLY ACHIEVING THE SAME POWER/LOAD WITH LESS BOOST DUE TO COLDER TEMPS.

Now let's use your logic. If temps go down, COBB car will lower boost and make the same power. JB4 will make slightly higher power because it's targeting the same boost with denser air (colder).
How about when temps go higher?
COBB will increase boost, and hit the same power. JB4 will target the same boost on thinner air and make less power

Same applies when you go high in altitude... COBB will compensate, JB4 won't.

[E90Company]

Originally Posted by wahooooman

Jb+ stage 2, Boost controller, for not fiddling with the ecu area, easy install adds some power, maybe enough for you!!!



Hmm, this is interesting to me i didn't realize that running 18ish psi on stock dps would be a problem, makes sense now due to the pressure, but on my jb4 Map5 i am running 16-17-18psi ...a lot of the time, should i be concerned ? Thanks

Well the higher you boost on stock downpipes means the less life your turbos will have. Backpressure kills turbos

[Joshboody]

The theory of load targeting is nice, and works to point with conservative tuning targets. But when you are trying to maximize HP, your winter tune is not so nice to you in the summer. And your summer tune is dull in the winter.

JB will compensate for altitude btw.

[E90Company]

Originally Posted by marv85

The basic logic of a piggy is not better, it's as you mentioned basic (dumb).

COBB (BMW DME logic/tuning) does not target boost. It targets load. Load can vary due to many variables. Boost being one of these variables.
The DME will try to achieve the target load with the least boost possible. When the temp drop, the car will be able to achieve the target load with less boost and hence it reduces the boost. that's not a bad thing. YOU ARE NOT LOSING POWER DUE TO THIS, YOU ARE ACTUALLY ACHIEVING THE SAME POWER/LOAD WITH LESS BOOST DUE TO COLDER TEMPS.

Now let's use your logic. If temps go down, COBB car will lower boost and make the same power. JB4 will make slightly higher power because it's targeting the same boost with denser air (colder).
How about when temps go higher?
COBB will increase boost, and hit the same power. JB4 will target the same boost on thinner air and make less power

Same applies when you go high in altitude... COBB will compensate, JB4 won't.

Isn't this methodology putting a huge strain on the turbochargers when it is hot? I feel like turbo health would be more important than power no?

Genuinely curious, not sarcastic

[marv85]

Originally Posted by Joshboody

The theory of load targeting is nice, and works to point with conservative tuning targets. But when you are trying to maximize HP, your winter tune is not so nice to you in the summer. And your summer tune is dull in the winter.

When your goal is to maximize, then that is a downside of Load targeting. You'd need probably two maps.

however, if you want to maximize then autotuning is not enough. Custom tuning (whether done by the user, or a prof I mean) is the way to go.

[Jeff@TopGearSolutions]

Originally Posted by marv85

This is the only post that makes sense in all this thread. I've read through and I'm tired of responding to silly comments about COBB boost, and JB4 being safe or the other way around...

Thanks for posting this Jeff

Thank you.

Originally Posted by E90Company

Well the higher you boost on stock downpipes means the less life your turbos will have. Backpressure kills turbos

Originally Posted by E90Company

Isn't this methodology putting a huge strain on the turbochargers when it is hot? I feel like turbo health would be more important than power no?

Genuinely curious, not sarcastic

The turbo's are still run in their efficiency range. If you are using the correct map for your modifications whether its hot or cold, Cobb is within the efficiency of the turbo's.

If you are running stock downpipes, then you will be on stage 1* maps, therefore within the efficiency range for stock downpipes and turbo's.

If the quest is for limited abuse of the turbo's, stay on stock boost, any modifications to your vehicle and any increase in power will theoretically wear components faster, machines will fail over-time, that much I can assure everyone here.

There is so significant evidence to support Cobb's OTS maps are out of efficiency, and blowing turbo's.

Originally Posted by marv85

When your goal is to maximize, then that is a downside of Load targeting. You'd need probably two maps.

however, if you want to maximize then autotuning is not enough. Custom tuning (whether done by the user, or a prof I mean) is the way to go.

I agree.

Load targeting has its drawbacks;
If anyone is looking for the most optimized tune, you would basically need to tune your vehicle everyday, as conditions change like humidity, temperature, and heat soak of the vehicle so does the changes of your boost, fueling and ignition.

A good tune will find a happy medium. That is when conditions worsen the tune will be safe enough and still make good power, by no accident, this swings both ways for temperature, cold and hot.

Load Targeting is backwards from an optimization standpoint of hot or cold tuning, the upside is you maintain (in theory) similar power in all conditions.

[themyst]

Originally Posted by jippii ensio

When temps drop, Cobb etc flash tunes decrease boost whereas piggies increase the boost. So, the basic logic of a piggy is a lot better. This can be noticed even within a day when the day is hot and night is cold.

It is also well known that the off the shelf Cobb tunes leave a lot on the table and the above logic problem is one reason for it.

A custom Cobb tune is even more dollars, but even that does not get rid of the problematic logic.

Correct on stage 1 logic, incorrect otherwise.

Targeted load should be called load limit actually as boost is controlled through the WGDC tables.

[Joshboody]

Originally Posted by Jeff@topgearsolutions

The turbo's are still run in their efficiency range. If you are using the correct map for your modifications whether its hot or cold, Cobb is within the efficiency of the turbo's.

If you are running stock downpipes, then you will be on stage 1* maps, therefore within the efficiency range for stock downpipes and turbo's.

If the quest is for limited abuse of the turbo's, stay on stock boost, any modifications to your vehicle and any increase in power will theoretically wear components faster, machines will fail over-time, that much I can assure everyone here.

There is so significant evidence to support Cobb's OTS maps are out of efficiency, and blowing turbo's.

This whole “turbos in the efficiency range” is a little misleading. What does this mean and how does it relate to turbo life? Efficiency is just referring to theoretical heat versus density and within this range we aren’t choking the turbos. But this doesn’t have any indication of what’s happening on the turbine side. I’m not one to answer this, but I suspect people interpret this statement incorrectly.

[Jeff@TopGearSolutions]

Originally Posted by Joshboody

This whole “turbos in the efficiency range” is a little misleading. What does this mean and how does it relate to turbo life? Efficiency is just referring to theoretical heat versus density and within this range we aren’t choking the turbos. But this doesn’t have any indication of what’s happening on the turbine side. I’m not one to answer this, but I suspect people interpret this statement incorrectly.

I think I’m just a little bored today

Turbo's have a compressor map, and their efficiency range, that is what it is referring to.

As far as Turbo Life goes, these turbo's have failed on stock boost levels, so roll the dice.

[jippii ensio]

Originally Posted by marv85

The basic logic of a piggy is not better, it's as you mentioned basic (dumb).

COBB (BMW DME logic/tuning) does not target boost. It targets load. Load can vary due to many variables. Boost being one of these variables.
The DME will try to achieve the target load with the least boost possible. When the temp drop, the car will be able to achieve the target load with less boost and hence it reduces the boost. that's not a bad thing. YOU ARE NOT LOSING POWER DUE TO THIS, YOU ARE ACTUALLY ACHIEVING THE SAME POWER/LOAD WITH LESS BOOST DUE TO COLDER TEMPS.

Now let's use your logic. If temps go down, COBB car will lower boost and make the same power. JB4 will make slightly higher power because it's targeting the same boost with denser air (colder).
How about when temps go higher?
COBB will increase boost, and hit the same power. JB4 will target the same boost on thinner air and make less power

Same applies when you go high in altitude... COBB will compensate, JB4 won't.

When temps drop, a good tune such as JB or Procede will be able to benefit from the denser air. You are saying that in that situation Cobb cannot make more power but only "THE SAME POWER" as in higher temps. That is true and unfortunate.

When temps go higher COBB tries to make the same power as with colder temps, as you say, and that exactly is the problem. You are stressing out the turbos or having ignition drops. Moreover, Cobb is still NOT making more power than piggies in warmer temps. Generally speaking Cobb is just making less power than piggies in colder temps, i.e. denser air.

[GTstunna612]

some very nice info...gonna go with the JB4 Tune with my DCI