[AWD Addict]

That's not a lot of lag. THis car has almost zero turbo lag. Try driving in a big blower STi, and waiting till 4500rpms to get boost.

1-2 seconds is nothing.

[Dr_Dirt]

Originally Posted by Dickson

Hey guys I'm running Cobb stg 1 aggressive 4.0 and I feel like I have a substantial amount of turbo lag. My only other mod is Injen DCI. For example, if I am cruising at 50 mph in 3rd gear and I put the pedal to the floor, it takes at least 1-2 seconds before I feel the rush of the turbos kicking in (I do hear them spooling almost immediately though). But, the lag is certainly noticeable. This is not something new with 4.0 as it has been happening for as long as I can remember. I am not throwing any codes last time I checked on the Cobb. Until I did some reading, I thought this much lag was normal.

After reading some threads, many people say the n54 has very little noticeable turbo lag and that any lag may be attributed to a software update to fix wastegate rattle issues. Could that be my problem here, or does the Cobb flash overwrite these possible issues with the car's computer?

Any guidance is appreciated. If I should log a run, advice on what parameters to log would also be helpful. Thanks.

Maybe you loaded the LT (linear throttle) try the ST (stock throttle)

[Dickson]

Originally Posted by Dr_Dirt

Maybe you loaded the LT (linear throttle) try the ST (stock throttle)

I am using the stock throttle maps. I tried the linear first, but really didn't like it for driving around the city.

[2Times]

Originally Posted by Dickson

I am using the stock throttle maps. I tried the linear first, but really didn't like it for driving around the city.

I'd go back to the 301 map to see if there is any difference. It's all preference. I like the 400 map because the WG rattle is a little less lol, otherwise I'm fine with either.

[crypticc]

Originally Posted by AWD Addict

Show Off! .

[off topic]
I do occasional heel and toe and never triggered that code. P.s. I it used to be traditional to use inwards turned foot for heel and toe, (big toe downwards) but on BMW seems is easier to use outward turned foot (big toe upward). Anyone else find that? [/off topic]

[BMWsky]

Originally Posted by crypticc

[off topic]
I do occasional heel and toe and never triggered that code. P.s. I it used to be traditional to use inwards turned foot for heel and toe, (big toe downwards) but on BMW seems is easier to use outward turned foot (big toe upward). Anyone else find that? [/off topic]

No, not at all!

[adidasoccer]

First time monitoring boost since i installed v400 today and my boost with a cold engine reads -0.1 psi where before during a cold start it would read anywhere from -11.2 -> -10.2... has the software changed or is something wrong im picking up no codes and im not feeling any lack of power

[skim7x]

How are you measuring your boost? If it's a direct line, then you may have a boost leak or you may need to re-calibrate your boost gauge.

If you're reading it from the Cobb AP via the OBDII port, that's another story and I can't help you there as I've never monitored boost off my Cobb AP. If you were measuring -11psi before and now closer to 0, then you may still have a boost leak... Did you have any engine bay work done recently? Especially an FMIC install?

[adidasoccer]

never touched a thing in the engine just the cobb ap and i am monitoring using the cobb and peak boost is on par with what i was holding before so i have no idea

[paapaa]

at last got to Stage2+ in my AT

installed first V301 Sport ST,was fun
now changed to V400 Sport LT and its huge change...i mean with LT you press a little the pedal down and its starts on pulling...but with ST you will have to press much more to start the pulling...dont really know yet, which one i prefer is better..LT ot ST. i think its easier to control cas mileage with ST but its more fun with LT ...god damn...its like 2 good movies and you have to pick one

power with the Stage2+ is massive compared to my previous Stage1 remap

[Cozy]

Originally Posted by paapaa

at last got to Stage2+ in my AT

installed first V301 Sport ST,was fun
now changed to V400 Sport LT and its huge change...i mean with LT you press a little the pedal down and its starts on pulling...but with ST you will have to press much more to start the pulling...dont really know yet, which one i prefer is better..LT ot ST. i think its easier to control cas mileage with ST but its more fun with LT ...god damn...its like 2 good movies and you have to pick one

power with the Stage2+ is massive compared to my previous Stage1 remap

Do you not have Stock Throttle & Linear Throttle mixed up here? ST should be the one which gives you 90% power at half throttle and LT the one which progressively builds the harder you push the pedal down.

[paapaa]

Originally Posted by JamJay

Do you not have Stock Throttle & Linear Throttle mixed up here? ST should be the one which gives you 90% power at half throttle and LT the one which progressively builds the harder you push the pedal down.

seems that i didnt express myself correctly...should have said ST you have to press down quite a bit before nothing happens...thats why the LT seems
nicer...allways ready to jump with a little push of the pedal. well ayway...i know exactly what you mean but english is not my native so sometimes
cannot say thought so clear...easier to control the power with LT because power is in so wide push area of pedal...with ST its much narrow area to control
all the power you want.

BTW do you have to set the AP to record logs or something to see if misfiring or else occurs? or should i see something on dashboard?

[enrita]

Originally Posted by paapaa

seems that i didnt express myself correctly...should have said ST you have to press down quite a bit before nothing happens...thats why the LT seems
nicer...allways ready to jump with a little push of the pedal. well ayway...i know exactly what you mean but english is not my native so sometimes
cannot say thought so clear...easier to control the power with LT because power is in so wide push area of pedal...with ST its much narrow area to control
all the power you want.

BTW do you have to set the AP to record logs or something to see if misfiring or else occurs? or should i see something on dashboard?

you will notice if it missfire. pretty hard to miss. Normally the cell/SES light comes up as well.

[BMWsky]

Originally Posted by JamJay

Do you not have Stock Throttle & Linear Throttle mixed up here? ST should be the one which gives you 90% power at half throttle and LT the one which progressively builds the harder you push the pedal down.

I thought I was crazy, but I agree with Paapaa. I had a problem with version 4.00 so Cobb sent me version 4.01 (IJEOS). On stage 1+ and 2+, I noticed that the LT felt like it spooled the turbo's quicker, but that ST still had that spike that I was used to. At least on my maps, the LT feels like it pulls stronger and more consistantly early and all the way through the RPM range. The ST map still feels like the throttle position is at 100% very early on the accelerator pedal, but that smooth delivery of power I'm getting on 4.01 Stage 2+ is really nice. I feel it as soon as I press the pedal.

[utfenix335i]

I am running V400 LT Stage 2 + FMIC aggressive right now... and I daily drive my car. I'm noticing at cruising speed that I am having some kind of power fluctuations. I'm wondering why i might be. When i'm at a light, my revs sometimes drop to 500 rpm.

My supporting mods:
3'' catless dps
Mr. 5 intake (upgraded K&N drop in married with a spectre 3'' in the fender)
Active Autowerke FMIC v2
stock exhaust

Please advise.

[rader1]

what exactly do you mean power fluctuations? Can you feel it or is it a change in the exhaust note?

[utfenix335i]

Originally Posted by rader1

what exactly do you mean power fluctuations? Can you feel it or is it a change in the exhaust note?

I can feel it. it's like it's throttling then drops then goes up again... kinda like a rocking but gentle. Goes away when I put it on cruise control (sometimes). Wasn't a problem with my procede Rev2.5 module.

[enrita]

Originally Posted by utfenix335i

I can feel it. it's like it's throttling then drops then goes up again... kinda like a rocking but gentle. Goes away when I put it on cruise control (sometimes). Wasn't a problem with my procede Rev2.5 module.

do you experience it at low rpm steady cruise very light throttle ? i had similar same issue cured by changing vacuum hoses and canisters.

[rader1]

Originally Posted by utfenix335i

I can feel it. it's like it's throttling then drops then goes up again... kinda like a rocking but gentle. Goes away when I put it on cruise control (sometimes). Wasn't a problem with my procede Rev2.5 module.

I've never had this issue but if you could provide some logs showing this happen maybe someone can help you out.

[themyst]

Originally Posted by adidasoccer

First time monitoring boost since i installed v400 today and my boost with a cold engine reads -0.1 psi where before during a cold start it would read anywhere from -11.2 -> -10.2... has the software changed or is something wrong im picking up no codes and im not feeling any lack of power

It's fine. Cobb redid how they read boost off the TMAP so it is accurate in the higher RPMs

[skim7x]

I just think that if you're serious about your car, it's always a good idea to get a good, simple boost gauge...

[rader1]

Originally Posted by skim7x

I just think that if you're serious about your car, it's always a good idea to get a good, simple boost gauge...

That's definitely not bad advice, but the AP doesn't have the reputation of being misleading(lying) about AFRs like some other tune does. I just wish there was a clean, factory like gauge for the 1s(I'm not a fan of the P3.)