Dyno'd my 15 psi greddy
#1
Dyno'd my 15 psi greddy
Power
Torque
Made 243.2 bhp, & 237.2 ft/lbs.
There were two dyno runs, the dotted line is the second dyno run.
Still some issues to work out, need to better setup fueling/timing above 4500 RPM. Pulling way too much timing top end. Looking forward to getting her back on the rollers for try #2
Not too shabby for a Greddy
Torque
Made 243.2 bhp, & 237.2 ft/lbs.
There were two dyno runs, the dotted line is the second dyno run.
Still some issues to work out, need to better setup fueling/timing above 4500 RPM. Pulling way too much timing top end. Looking forward to getting her back on the rollers for try #2
Not too shabby for a Greddy
Last edited by tritium; 10-30-2007 at 09:51 AM.
#5
Boost actually creeps up to about 16 psi at redline, but think I'm pulling way too much timing. I'm pulling the same amount from 5500 RPM onwards, so suspect I could fix this with a few map adjustments. I just wish I'd known this before putting her on the dyno. If it weren't for the torue drop, I'm guesstimating I could've been seeing comfortably over 250 bhp.
#9
Interesting that you should mention that, I waited 6 months for mine...
Here she is on the dyno:
http://www.youtube.com/watch?v=pAJfbe7h-AM
Here she is on the dyno:
http://www.youtube.com/watch?v=pAJfbe7h-AM
Last edited by tritium; 10-28-2007 at 04:31 PM.
#10
Boost Czar
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i stand by my "all you greddy guys need to replace your wastegates" statement.
nice numbers regardless of the torque drop.
i can't believe it creeps us, not with that drop, the hp should be about 20-30 point higher than the torque if the boost held flat.
but again, regardless, it looks like fun.
nice numbers regardless of the torque drop.
i can't believe it creeps us, not with that drop, the hp should be about 20-30 point higher than the torque if the boost held flat.
but again, regardless, it looks like fun.
#11
Boost definitely isn't dropping, I'm 100% sure of this.
If you wish, I can show you datalogs right up to near 20 psi at redline, where you can clearly see the boost is increasing (creeping) right up to redline.
#16
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What have you done to make pressure rise towards redline? Every other greddy falls towards redline.
I'm also curious what your intake temps were looking like. I'm wondering if you were loosing power due to the turbo being past its range. At 16 psi in the mani, that could be 20 psi at the compressor outlet.
I'm also curious what your intake temps were looking like. I'm wondering if you were loosing power due to the turbo being past its range. At 16 psi in the mani, that could be 20 psi at the compressor outlet.
#17
The main problem appears to be that I was overfueling. If you watch the video I posted of the dyno run, at the end of each pull you can hear the engine starting to misfire. This is because as the boost is creeping up it is entering a new region of the fueling map, which wasn't setup efficiently.
I was also pulling too much timing top end. This morning I've spent 5 hours rebuilding the fueling map from scratch, pixel by pixel from datalogs. Its now in its third revision and top end has improved from before. The dyno will say all, just as soon as I can get around to doing that I will.
So far I've only added 1.5 degrees advance beyond 5500 rpm and no sign of knock as of yet, and its helped.
I had run autotune the day before the dyno to try and even out the peak boost AFRs (little boost overshoot) but I'm guessing the LC-1 wideband was perhaps out of calibration and messed up the region of the map between 15 & 18 psi (for safety it was tuned to 18 psi prior to the dyno run).
Ben, I'm using a helper spring to hold the wastegate shut until 12 psi.
I can see from datalogs that boost isn't dropping off.
I was also pulling too much timing top end. This morning I've spent 5 hours rebuilding the fueling map from scratch, pixel by pixel from datalogs. Its now in its third revision and top end has improved from before. The dyno will say all, just as soon as I can get around to doing that I will.
So far I've only added 1.5 degrees advance beyond 5500 rpm and no sign of knock as of yet, and its helped.
I had run autotune the day before the dyno to try and even out the peak boost AFRs (little boost overshoot) but I'm guessing the LC-1 wideband was perhaps out of calibration and messed up the region of the map between 15 & 18 psi (for safety it was tuned to 18 psi prior to the dyno run).
Ben, I'm using a helper spring to hold the wastegate shut until 12 psi.
I can see from datalogs that boost isn't dropping off.
#20
Please see post #11 here:
https://www.miataturbo.net/forums/sh...=helper+spring