Took car to dyno today, have fuel issues
#41
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well the strange thing is the printout says I got up to almost 14 psi, but the video I posted of the same run only shows me getting a little over 12 psi. Strange. As for the psi range, I also heard that running over 12 is iffy with a stock NB engine. 2001 and up is worse because they have a higher compression ratio than the 99/00.
After driving around for a week with the new setup, I CAN'T WAIT for the new fuel pump. Every time I get into boost, I can watch my fuel gauge go down. Feels like when we used to have the SS Camaro... It is dumping in SO much fuel... Oh well, at least it is safe but I will have to pay to have it retuned when I put in the new fuel pump :(
After driving around for a week with the new setup, I CAN'T WAIT for the new fuel pump. Every time I get into boost, I can watch my fuel gauge go down. Feels like when we used to have the SS Camaro... It is dumping in SO much fuel... Oh well, at least it is safe but I will have to pay to have it retuned when I put in the new fuel pump :(
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Went back to the dyno today to have him do some more tuning. I REALLY need to get around to installing this fuel pump... According to the log, I am hitting 65-100% duty cycle to keep the AFR under control. So, I am going to install the new pump this weekend, and hopefully it will allow the injectors to do what they need to do.
The only other thing I see is that the boost is getting a LOT higher than I have it set for. The realtime display on my laptop shows it just touching 14psi then settling down to 12. According to this log, I am getting 16psi![](https://www.miataturbo.net/images/smilies/eek.gif)
Can you see any other issues I need to address?
The only other thing I see is that the boost is getting a LOT higher than I have it set for. The realtime display on my laptop shows it just touching 14psi then settling down to 12. According to this log, I am getting 16psi
![](https://www.miataturbo.net/images/smilies/eek.gif)
Can you see any other issues I need to address?
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This is a log from when I was driving home, not on the dyno. Is there a good way to get a power estimate from megalog viewer? I haven't played with it that much to know how to get calculated fields from a log file.
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one more question: if I changed out the rear differential from a 4.3 to a 3.9, will the vehicle speed sensor be off? I haven't changed the speedo gear yet, so I assume it will be. I ask because I am trying to get an estimate of 0-60 times and I think I have to back calculate for a different indicated speed.
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