datalog: AIT, boost
#1
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datalog: AIT, boost
Just looked at a log from the last time I took the car out to log some full throttle boost runs. Ambient was 80f, air intake temp was 28.4c/83f at the start of the boost run - 1700rpm. AIT rose to a peak 44c/111f at 7000rpm. Boost onset was 1900rpm, peaked 13.8 psi at 4000rpm eventually falling off to 12.2psi. I've got a tiny spearco cored IC - core is 3x16x6. Anybody have any similar data?
Also notice how much the boost falls off after it peaks at 4k rpm. It settles down to just over 12psi around 6k rpm and holds that until the end of the run at 7k. I've seen worse, and I've seen better, but better is usually on an external gate. I'm running an internally gated t3 .48AR turbine. Am I seeing the internal gate trying to "catch up"? I've moved the signal hose over to the manifold and got identical results. - rob
Also notice how much the boost falls off after it peaks at 4k rpm. It settles down to just over 12psi around 6k rpm and holds that until the end of the run at 7k. I've seen worse, and I've seen better, but better is usually on an external gate. I'm running an internally gated t3 .48AR turbine. Am I seeing the internal gate trying to "catch up"? I've moved the signal hose over to the manifold and got identical results. - rob
Last edited by m2cupcar; 04-17-2007 at 03:48 PM.
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helper spring installed and tested
My helper springs set up consists of a small link on the flapper arm with the spring running to a turnbuckle eye bolt, which runs through the wg can bracket and is double nutted on the other side. - rob
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helper spring 2
Just made another logged run. This run had the rod/spring tightened about 3/16". The boost curve is again similar, this time a greater differential between peak and low, and the overall boost at mbc stop to redline is higher. It looks to me that what I'm seeing now is something that can be helped by the spring, but not resolved. Perhaps a limitation on the stock internal gate design? Comments? - rob
dashed line = boost, bottom green = rpm, orange = AF, green = AF target
dashed line = boost, bottom green = rpm, orange = AF, green = AF target
#8
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Yes. I spent a good amount time trying to get it work (and doubting my IQ) only to figure out that I've got a dead component on my link board.
I know where the component is located on the board, just need to confirm the exact specs (have the location) and then swap it out.
Decided to run the mbc just so I could drive the car and get it tuned, rather than working on one more thing that keeps the car sitting in the garage.
* Something else I noticed on the logs was that I have no spike when I'm running through the gears. Only spikes when I do a boosted run from a low rpm. Perhaps another indicator that there's more at "fault" than the actuator.
I know where the component is located on the board, just need to confirm the exact specs (have the location) and then swap it out.
Decided to run the mbc just so I could drive the car and get it tuned, rather than working on one more thing that keeps the car sitting in the garage.
* Something else I noticed on the logs was that I have no spike when I'm running through the gears. Only spikes when I do a boosted run from a low rpm. Perhaps another indicator that there's more at "fault" than the actuator.
Last edited by m2cupcar; 04-17-2007 at 03:48 PM.
#9
Good info.
I know from my dyno runs that the spring did help smooth out my boost curve above the 8-9 psi range. It definitely wasn't a perfect fix at the time though. My wastgate looked like it was still leaking a lot above 9. I figured it just needed to be messed with a bit which i didn't have the time to do before more runs.
I think I've messed with mine as much as I can. I just need to get a couple of runs in to se if anything has been resolved.
I know from my dyno runs that the spring did help smooth out my boost curve above the 8-9 psi range. It definitely wasn't a perfect fix at the time though. My wastgate looked like it was still leaking a lot above 9. I figured it just needed to be messed with a bit which i didn't have the time to do before more runs.
I think I've messed with mine as much as I can. I just need to get a couple of runs in to se if anything has been resolved.
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