Möbius build 3.0 : Crash testing Miatas like he works for the NHTSA
#324
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Megasquirt logs? No. Ebc was definitely on, 7psi spring. Duty cycle graduated from 20 to 24 (ish) iirc to flatten out the torque. Steady state ebc showed consistent about 20kpadrop from torque peak to redline.
#325
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Megasquirt logs? No. Ebc was definitely on, 7psi spring. Duty cycle graduated from 20 to 24 (ish) iirc to flatten out the torque. Steady state ebc showed consistent about 20kpa drop from torque peak to redline. Same for wastegate only, roughly, but at lower kpa of course.
#328
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Real life pulls otw to pick up my borrowed tow rig (has miata, not a member of this forum though) gave me 193kpa peaks. I have boost cut set at 200kpa.
Serious question - where should I set max long term boost for stock cast pistons at 10:1 compression? I was hitting 180kpa on the dyno. It was quite a bit cooler this morning though, which I assume accounts for the 193kpa peaks. Those were also 3rd and 4th gear pulls fwiw.
Edit: my dyno tuner has just informed me he did the rest of the table good to 18-20 PSI, so it's not like I'm venturing into completely untuned territory. Unverified, but potentially guesstimated correctly for stock pistons.
I've gotten FB questions from my two miata group posts about why no forged pistons, and why no #allofit. This car has never been about #allofit. We have(had) Fae, and now Aidan, to carry that torch for us. I'm about "drive the everloving **** out of it and take it home intact." The motor is overbuilt for what I'm asking of it, which is by design, except for maybe at this point the pistons. Which, for those not in tune with the history of my vehicle, I maintained stock pistons and 10:1 compression so as when I had to meet my OBD2 emissions requirement it was one less thing the ECU could possibly bitch about. I had an Xede for the bigger injectors and for boost and for everything else but I didn't know what dropping the CR would do to the stock ecu's happiness.
Emissions are no longer ever again a concern for my car in Oregon, so 8.6:1 is now possible. But in the future.
Log attached for those interested.
Serious question - where should I set max long term boost for stock cast pistons at 10:1 compression? I was hitting 180kpa on the dyno. It was quite a bit cooler this morning though, which I assume accounts for the 193kpa peaks. Those were also 3rd and 4th gear pulls fwiw.
Edit: my dyno tuner has just informed me he did the rest of the table good to 18-20 PSI, so it's not like I'm venturing into completely untuned territory. Unverified, but potentially guesstimated correctly for stock pistons.
I've gotten FB questions from my two miata group posts about why no forged pistons, and why no #allofit. This car has never been about #allofit. We have(had) Fae, and now Aidan, to carry that torch for us. I'm about "drive the everloving **** out of it and take it home intact." The motor is overbuilt for what I'm asking of it, which is by design, except for maybe at this point the pistons. Which, for those not in tune with the history of my vehicle, I maintained stock pistons and 10:1 compression so as when I had to meet my OBD2 emissions requirement it was one less thing the ECU could possibly bitch about. I had an Xede for the bigger injectors and for boost and for everything else but I didn't know what dropping the CR would do to the stock ecu's happiness.
Emissions are no longer ever again a concern for my car in Oregon, so 8.6:1 is now possible. But in the future.
Log attached for those interested.
#329
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I have a very similar motor in Rover, ACL/ARP/Manley bottom end but stock 83mm 9:1 slugs and a stock oil pump. On E85, I would feel comfortable running it at 280-300whp. On gas, a little less comfortable, since the cast piston will be way, way less tolerant of any little puffs of knock, so I don't know if I would push too much past the 250whp mark on gas with your current pistons.
#335
Your boost cells look rather close to my map. I have the same stock 10:1 pistons. The motor has done ~20 track days without any major issues at 170kpa.
My local track is at 5200ft elevation; not sure if that helps/hurts detonation... The turbo is certainly working harder, but the air composition/density is a lot different.
My local track is at 5200ft elevation; not sure if that helps/hurts detonation... The turbo is certainly working harder, but the air composition/density is a lot different.
#336
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On this map, advancing timing yielded no power. So not sure how I can run "way more timing."
We didn't do any partial throttle sweeps. I wanted to, but things ran way late and I need to go. Being able to track it safely and get the ebc set was my goal and I think that's been achieved.
This will be revisited when the 3" exhaust goes on. I'll bug Curly to come participate and bribe him with beer.
We didn't do any partial throttle sweeps. I wanted to, but things ran way late and I need to go. Being able to track it safely and get the ebc set was my goal and I think that's been achieved.
This will be revisited when the 3" exhaust goes on. I'll bug Curly to come participate and bribe him with beer.
#339
"cells that you'd never visit" are often visited at the most random times, and then you see det or roughness or inefficiency. If it's temp/interim all of this is acceptable and I have no issues with it.
#340
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/\ "Idle timing high." Depends on if he is using idle timing. I set idle timing at 10*, and use correction for stability. Then, as soon as throttle goes above 1.5% or whatever, timing goes to 15* as he has it. Allows stable idle with a little bump in power coming off idle. A thought.