Just installed 243 heads and BTR Cam. I know the car may not make power all the way to 7k RPM but I am kind of stumped on what limiter I am missing. I turned the fuel cutoff all the way to 12k, Abuse modes off, Car hits a hard limiter around 6500rpm. Was going to the track tomorrow to dial in shift points.
Its either something simple that I am overlooking or something weird with this early model PCM.
1997 Silver Corvette V0012 braf, STARTUP AIRFLOW.hpt
C5 6500 LIMIT.hpl
i can help you
pm me
Originally Posted by Mikeloko
Why don't you help him here? Why does he have to PM you?
OP you're logging WAY TOO MANY pids for a 97-98 car. You need to cut nearly all of them out. You aren't even logging throttle position probably the most important pid to solve this.
Need to keep your pid list to less than 10 for this car. RPM, timing, throttle position, temp, MAF, MAP, speed, not much more than that.
The reason is the data rate is way too slow the more pids you add. If you look through the log you can even see some of the pids stop moving completely like they turn off.
Or you can PM the other guy.....
BTW the problem is most likely in the trans torque management.
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Yeah I didn't understand the DMing either. Thanks for the help, I'm just going to turn off all of the torque management and test it.
I'm not at a computer to check your log but I had this issue on the dyno when my fueling was way too rich.
Your log shows you going over 6500, almost 6800, if you have stock 243's you're prob encountering valve float. But not logging tps we can't see what you're doing really. Log on a road with load...not great free revving to 7k...
I meant to comment on this a couple days ago.
This doesn't look like a limiter to me. Log throttle position. It's holding spark and fuel. The only way it could be limiting it is with throttle at this point.
I'll bet its a valve train issue or something along those lines.
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It looks like it falls off too smoothly for valve float. That usually looks more jagged. Not smooth and not abrupt like the throttle slammed shut or timing went away.
Although the way it looks like in a line graph may not be an accurate depiction because of the logging issues due to too many pids. So, first thing to do is get rid of everything but the bare minimum and add TPS %. That way it should log much quicker. FPS
Last edited by edcmat-l1; 4 Days Ago at 10:27 AM.
EFI specialist
Advanced diagnostics, tuning, emissions
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email=[email protected]
Ya, what's the valve train consist of? What are the spring specs, seat psi, and over the nose psi? Where exactly in the .HPL file does it hit a limit? I see a free rev to 6780 rpm with less than 50% APP. What does the log look like do under load, something like second gear WOT?
I'm going to take a new log now. It is the BTR red hot cam with their .660 springs and steel retainers. I bought the whole kit including their pushrods. It will sometimes rev in park over 6500 but in gear it feels like the factory kind of rev limit right before the shift.
Well, pretty useless. The logger still freezes at high RPM and does not accurately display what is happening in the vehicle.
Its seems to be acting a little better. It bumps "a limiter" one time on the 1-2 shift and then shifts good.
The first pull in this log shows a 2nd gear pull, pulled smooth to 63/6400 and shifted and I got off the pedal.
The middle two pulls are 1st gear out to 6300+rpm bumps the limiter, shifts, then I get out of the pedal.
The last Pull is 1st gear, shifts and I hold it out in 2nd gear and before it can make the 2-3 shift it hits that same limiter 4-6 times. None of that is visible on the log because for whatever reason it blanks out at the top of each gear.
silver c5 less PIDS.hpl
I’m on a phone so can’t see the log, but did you greatly reduce the number of channels you are logging? And also reduce the frequency on ones that aren’t changing very quickly?
I logged exactly 10 channels. I did not change any frequencies. You'd have to watch the log. Every channel besides RPM just stops and doesn't move at all for a few seconds.
what version of hptuner suite are you using
and what version of the equipment? Im still using MVP1
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