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Can you save a trifecta log as an xda and use virtual dyno?
I have no idea. I assume you are talking about converting the data of airflow and fuel into a power curve? I'm pretty sure trifecta's logs are locked down but I'm not certain. I'm thinking next time I hook up to a dyno I will do a couple pulls while logging for trifecta, and then hook up something like HPT just to datalog.
Virtual dyno is a program that creates a dyno graph based on weight and acceleration along with a log file.
So it sounds like I would have to do this on the street. How does it figure in aerodynamic resistance? If it doesn't it will get further and further off the faster speeds I log. I may be able to do something like that with my Bluetooth OBD reader.
HP and Torque go hand in hand which is why they always cross at 5252 rpm. You can't have one without the other so i'm not sure why your wanting to ignore one but to each their own.
HP and Torque go hand in hand which is why they always cross at 5252 rpm. You can't have one without the other so i'm not sure why your wanting to ignore one but to each their own.
Exactly, horsepower is a calculated figure from torque and rpm so why would I worry about it? I am trying to figure out why my torque curve does not sustain like it should into the upper rpms. This would also correlate to a higher peak HP. If I am concerned about my torque not holding out like it should why should I also be concerned with the HP line not continuing to climb like it should when it is essentially the same thing? I can calculate Hp if I need to. No need to muddy the waters talking about hp being graphed correctly with respect to torque and rpm as that makes no difference for what I am trying to figure out.
If I am concerned about my torque not holding out like it should why should I also be concerned with the HP line not continuing to climb like it should when it is essentially the same thing?
My issue is torque taking a nose dive waaay too early. That also makes hp nosedive but hp is just (Torque x RPM)/5252. So when my concern is my torque dropping off before it should what does the HP line being displayed correctly or incorrectly have to do with anything I'm concerned about? I could plot my own hp line if that was a problem. I'm trying to figure out is there something fucked up with my car or did something go wrong with the dyno. The HP line is irrelevant to the problem we are seeing here.
Alternatively I could concern myself with the HP line taking a nose dive before it should but as it is a calculated figure it makes more sense to me to focus on the actual variables instead of a calculated figure based on those variables.
So it sounds like I would have to do this on the street. How does it figure in aerodynamic resistance? If it doesn't it will get further and further off the faster speeds I log. I may be able to do something like that with my Bluetooth OBD reader.
Its a free program, go download it. You have to enter vehicle weight, tire size, frontal area, **** like that. Its not perfect but gets you the shape at least.
I can use my OBD scanner and app to get a glimps of the same thing. I just used it on my way back to work and did a 2nd gear pull up to around 7,500 rpm it was showing about 250 tq and 360 hp though it's just a live graph so I couldn't look real close. I'll probably mess around with that a bit more but I'm fairly confident at this point that the dyno was doing something funky towards the upper end and I'd also be surprised if I had as much low end torque as it was reporting though that is just an assumption based on other peoples results with similar setups.
Little over an hour away and I am already on their list. They are busy this time of year as some of the guys that run that shop are in fall harvest so I just told them to get a hold of me when things calm down.
For what it's worth.... I looked at your gauges during your road run and dyno run and it looked like the tach was 2-3 hundred rpm higher at the 120mph mark on the dyno. Any chance your clutch started to slip?
For what it's worth.... I looked at your gauges during your road run and dyno run and it looked like the tach was 2-3 hundred rpm higher at the 120mph mark on the dyno. Any chance your clutch started to slip?
I think about 130 is pegged for my speedo. It actually hits 120 and goes a bit further before it is maxed out which would be hard to tell from the camera angle. On the street pull I didn't reach the pegged position were on the dyno it reached the pegged position. I don't think clutch was slipping.
That's why I chose 120 to compare pulls to. The dyno pull looks like it's 200 - 300 rpm higher at 120 mph. In my opinion a clutch slip would have looked much different
Below is a screenshot from my OBD scanner app of a "virtual dyno" of sorts. I did a very short pull heading out of town in second gear up to 7,000 rpm. This may not be super accurate but it is close enough, combined with how it feels up top, that I am now convinced that there was an error on the dyno.
RPM scale on op left, airflow scale on top right, horsepower scale on bottom left, torque scale on bottom right.
You may have different issues arise in 4th that do not in second being under a much greater load. Most definitely cannot calculate Wheel HP accurately in 2nd.
Didn't say anything about calculating whp accurately in 2nd. Said this tells me enough to be confident that the dyno readings are way off, at least up top. And I am. I did some pulls using this same app in 3rd and got very similar results. Don't really have anywhere near me that I can go rev out 4th gear.
You ever get that second dyno done? I have seen this posted on several sites now.
When adding a lower pulley you also increase heat which needs to be controlled that is why you see many lower pullied cars making more TQ than HP. HP is lost at Hi RPM from heat generated from added blower speeds.
You ever get that second dyno done? I have seen this posted on several sites now.
When adding a lower pulley you also increase heat which needs to be controlled that is why you see many lower pullied cars making more TQ than HP. HP is lost at Hi RPM from heat generated from added blower speeds.
That's not my issue because my torque doesn't actually dive off. I would, without a doubt, feel this dive in torque in real world driving scenarios if it was actually happening. I am confident we incorrectly configured the loaded mustang dyno. I also have a standalone IAT2 gauge on which I monitored the post supercharger intake temperatures and can also verify that my temperatures did not increase in any way that would reflect correlation with this graph. In real world driving conditions it pulls hard all the way up to 8k rpm. But no I have not got it on a second dyno yet as the shop must have lost the supposed list they put me on. I am also not worried about it and probably won't put it on the dyno again until after autocross season is over.
10-19-2017, 07:52 AM
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