[yawn]

So after much deliberation, I finally removed my Cobb, and run the MHD flash stage 2. Took it for a spin, and noticed alot more power running through the gears. I have dps and intercooler upgraded but I'm only running stock twins, and fuel pump is stock also.

I am a bit concerned as I am hitting 20psi. There is alot of talk out there as to what is safe - it seems like as the years go by, the "safe limit" for the stockers also increases. I'm just wondering whether 20psi is what the stage 2 MHD is targeting? I have searched but cannot find what kind of boost levels I am supposed to be expecting. Furthermore, I am not too experienced with opening up a flash tune file and searching that way....

Also - I have read that the stock sensor detects up to 21.5psi of boost before you start going into unknown territory - can someone confirm this? I'd rather hope that the ceiling is not at 20psi, cos that could mean I am flying blind.

[kennejp]

I've been saying this forever. 20 psi is way to much for any daily driven car especially stock turbos. Somehow everyone has jumped on this MHD cheap flash bandwagon. Seen more local cars blow up from these tunes then all the other tuners combined. It's all risk and reward. There is a reason that jb4 maps and Cobb etc don't target more then 17ish psi. Just know a daily driven cAr at that boost level will only last so long.... My .02c

Originally Posted by sharkatron

I'd rather hope that the ceiling is not at 20psi, cos that could mean I am flying blind.

We're all flying blind without a log dude...can't help much without one.

[FIFTW]

Originally Posted by kennejp

I've been saying this forever. 20 psi is way to much for any daily driven car especially stock turbos. Somehow everyone has jumped on this MHD cheap flash bandwagon. Seen more local cars blow up from these tunes then all the other tuners combined. It's all risk and reward. There is a reason that jb4 maps and Cobb etc don't target more then 17ish psi. Just know a daily driven cAr at that boost level will only last so long.... My .02c

Are you sure it's not from injectors going out, HPFP/LPFP going out, water pump going out, spark plugs and coil packs going out. Wait? What about turbos going out from wastegate rattle? Or even VCG leaking, or the oil stand gasket?

am I missing anything?

[yawn]

Originally Posted by FCobra94

We're all flying blind without a log dude...can't help much without one.

Yeah I know someone was going to mention logs. I plan to. Though I do have a gauge t'ed into my vacuum lines so I can always check after a pull what the max boost reached was. And that's how I saw 20psi.

[yawn]

Originally Posted by kennejp

I've been saying this forever. 20 psi is way to much for any daily driven car especially stock turbos. Somehow everyone has jumped on this MHD cheap flash bandwagon. Seen more local cars blow up from these tunes then all the other tuners combined. It's all risk and reward. There is a reason that jb4 maps and Cobb etc don't target more then 17ish psi. Just know a daily driven cAr at that boost level will only last so long.... My .02c

I'm sure they know what they are doing - they are pioneering away, pushing the boundaries of what the n54 can do. The tuning community wouldn't get anywhere if it weren't for people like them. My concern is whether I should be hitting 20psi for their stage 2 map. And if I am, I should be considering an n20 sensor. And then whether or not I want to head down that track with stockers rather than a set of upgraded snails.

[E30 Racer]

Originally Posted by sharkatron

I'm sure they know what they are doing - they are pioneering away, pushing the boundaries of what the n54 can do. The tuning community wouldn't get anywhere if it weren't for people like them. My concern is whether I should be hitting 20psi for their stage 2 map. And if I am, I should be considering an n20 sensor. And then whether or not I want to head down that track with stockers rather than a set of upgraded snails.

The best thing you can do is log. That's really the only objective way to assess how well (or appropriate) a given tune is for your specific combination of car, fuel, mods, operating conditions, and overall health.

[Ilma]

Originally Posted by sharkatron

I am a bit concerned as I am hitting 20psi. There is alot of talk out there as to what is safe - it seems like as the years go by, the "safe limit" for the stockers also increases. I'm just wondering whether 20psi is what the stage 2 MHD is targeting? I have searched but cannot find what kind of boost levels I am supposed to be expecting. Furthermore, I am not too experienced with opening up a flash tune file and searching that way....

If you are hitting 20 psi as a spike in boost then that does not mean the tune is targeting 20 psi across the entire power band.

Boost spikes are normal during gear changes.

Your boost gauge is probably giving you the peak reading only.

You need a datalog to see what boost is doing across the entire rpm range.

Most of the stage 2 tunes will target 17-18 psi at low rpm and then taper boost down to 15-16 psi as redline approaches.

A transient spike up to 20 psi is very possible and of no concern.

My stage 2 tune hits 17 psi when I shift around 5500 rpms and I see a spike of 19 psi post-shift....which quickly corrects itself.

[2011z435is]

Originally Posted by sharkatron

Yeah I know someone was going to mention logs. I plan to. Though I do have a gauge t'ed into my vacuum lines so I can always check after a pull what the max boost reached was. And that's how I saw 20psi.

that tells you nothing important. You need to log...

[muncie21]

Boost is only 1 element to consider. When you log, you'll see timing, AFRs and trims (among other stuff) which help to determine how well you're car is working with the tune that's loaded.

[stanlalee]

Originally Posted by kennejp

I've been saying this forever. 20 psi is way to much for any daily driven car especially stock turbos. Somehow everyone has jumped on this MHD cheap flash bandwagon. Seen more local cars blow up from these tunes then all the other tuners combined. It's all risk and reward. There is a reason that jb4 maps and Cobb etc don't target more then 17ish psi. Just know a daily driven cAr at that boost level will only last so long.... My .02c

Just saying 20psi is too much is not saying anything at all. Peaking at 20psi at 4000rpm is harmless, peaking at 20psi at 5500rpm is a completely different scenario. 20psi with pump gas and 3 deg of timing advance at 4000rpm is harmless, 20psi with pump gas and 9 deg of timing advance at 4000rpm is a different scenario. 20psi at 4000rpm is not excessively hard on the turbo at all while 20psi at 5000rpm is a different scenario.

Point is because a tune kisses 20psi for a few hundred rpm in the turbos efficiency range does not automatically make it dangerous or overworked. 10 times out of 10 IF an OTS stage 2 tune is hitting 20psi that's all its doing. You can easily have a "peak" 16psi tune that is far more dangerous than a tune that peaks at 20psi.

[MatRamir646]

Hello, so I have a 335i 2007 n54 sedan, and I just finished tuning to stage 2+ after stage 2, this is because I really didn't feel any difference in stage 2, and in stage 2+ I still barely feel a difference ; I have bov , charge pipe , down pipes , intakes. I feel like it's supposed to have more power . Do you guys feel a major difference ?

[stewbets]

Welcome to the site!

Feelings are very subjective. To continue the theme of this [ancient] thread, you need to record some logs and see how the car is responding. Posting that information enables others on this site with far more knowledge to help you troubleshoot and evaluate.