Built motor + Speedtech ST build
- Thread starter d8rknight
- Start date
Was able to get on the dyno today ... best pass of the night 732/687 @33psi full e85. Guess I’m in the cool guys club. Special thanks to Midnite Tuning and V8bait with all the support. I can say I’m highly impressed with the build and look forward to building the rear end. Was changing boost pressure on the fly with GFBIII so I'd imagine once the DME learned the pressure i would be able to sustain/increase power to redline. no check engine lights ftw!
N54 6266 Dyno
N54 6266 Dyno
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later this year i will jump into the 8xx club.. just a matter of time tho 7xx is plentiful. SO glad i have the headroom to beat the car in the 700s w/o worrying of blowing the motor.
d8rknight, in your experience, do you believe closed deck is necessary for 780-800 whp?
Are you planning on a different turbo? I would figure out what is causing your dyno to nose dive towards redline at 6k 1st for what it is worth.
800whp should be possible with your mods @veer90 https://bmw.spoolstreet.com/threads/n54-6266-dyno-at-809whp-796-sae.4822/ <--this was without cams or head work. You have both.
810/755 vs. 730/690 my point being is I think you can get more out of your current set up, that is all.
Only reason it's not making more on the dyno is that the boost controller is peaking in the mid and not holding to redline. GFB can be frustrating like that. Doesn't happen on the street logs.
Is that because there is more load when you do a pull on the street do you think? I have heard multiple people complain about the GFB.
Why would someone choose to use the GFB over the stock DME w/ boost box out of curiosity? Especially when a flash is so quick?
Edit: If I am right about the load why does the GFB care about load at all when all it is supposed to do is control pressure? I don't know much about the GFB so perhaps I am missing something obvious. Personally I would want my boost controller to work on the street and dyno with no fluctuations if possible.
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Makes sense - dynojet drum weighs what - 2400lbs? Car weighs a good 1000lbs more, so more load on the street makes sense to me.
Why it does that I'm not sure. You can't adjust the duty curve, it learns slowly though. Happens on other cars too (lsx builds etc etc). There's controllers that you can tune duty on (stand alone systems generally, which I love since they work the PI too) but most external controllers have these issues. Upping the sensitivity helps some. Why not boostbox is more loaded of a question. I use boostbox a lot, but many people find it to not be the most reliable solution and it doesn't give you as much control without flashing maps, some like the external controllers and jb4 for that reason alone. Jb4 of course has many other downsides but does have the advantage of basic duty cycle mapping.
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I have the GFB as well. It's taken some time to get used to and I switched over to a 4port MAC with it so I could run more than 16psi with my 7psi spring. I've had some issues where it will just send boost to the moon like there's 100% duty. Thankfully the overboost feature works well but it's been problematic on track at times.
In regard to the power dropping off, it sounds like that's more a sensitivity setting than gain, which should help limit the taper. But perhaps the load variance is throwing it for a loop. Need a dyno setting and a street setting for it... stupid.
Solid numbers though here. Can't imagine wanting more power than that. Looks perfect.
Yes, sensitivity, thanks for the catch. But yeah on the dyno it's a lot different than street although it can struggle there as well which is frustrating, especially on stock engines from a torque perspective.
Filippo
Gives me peace of mind and a bit more assurance at the end of the day. there are only a handful of cars running at those power levels and a deck insert would be a best practice.
didn't mean to ignore you, but V8bait is the person tuning the car so I'm glad he chimed in.
