This is a supercharged Gen V Viper. WOT run, pedal 100%, throttle blade 54% at 3000 rpm and 64% at 6400 rpm.
Is this normal?
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This is a supercharged Gen V Viper. WOT run, pedal 100%, throttle blade 54% at 3000 rpm and 64% at 6400 rpm.
Is this normal?
I've had this happen on my mostly stock '08. What caused it was me increasing the values (on the order of +100 in the upper RPMs) in the peak torque calculation table. First and second gear were fine, but long pulls starting in 3rd gear would result in the throttle bodies only opening part way as you are describing. I realize that doesn't really help you fix the issue, but that's where I've encountered it. Does this look familiar? (throttle blade position is in blue):
https://i.ibb.co/ZVwHjz5/Throttle-Bo...ll-the-Way.png
It has something to do with how the PCM is interpreting the extra air flow of the blower. These PCMs are torque based, so something isn't matching up in the model compared to reality.
These PCMs have severe limitations when dealing with forced induction, and is why most folks switch over to a Motec or similar.
I think some folks have done a work-around by just slapping in some larger injectors, but leaving the injector tables stock. That'll let you scale the MAF tables down to compensate, keeping things closer within the bounds of the PCM. It isn't the "correct" way to do it, but if you aren't willing to make the jump to a different engine management system, that's what you'll end up having to do.
It looks pretty similar. As there is so much power and torq, it may have been missed by the previous tuner.Quote:
Originally Posted by MeentSS02
I think I will use scaling in this case. Injectors were flow-tested and they are 800 cc units, so roughly twice of the original ones. I will keep the injector data stock and deduct 50% from MAF and tweak ignition tables for half smaller resolution.Quote:
Originally Posted by MeentSS02
One of the MAFs is in the intercooler and that's the only one providing signal as the wiring has been altered. I will probably change it so that I will get better MAF data from the other MAF located at the charge pipe just before TB.
Sounds like someone has done some serious altering...interesting. Hope it turns out well.
Indeed.Quote:
Originally Posted by MeentSS02
Were you ever able to log MAF voltage?
I cannot find it from the scanner PIDs. But I guess I could use MPVI2 analog input to log it from the MAF signal.
That was included in the enhanced PIDs for the Gen 4s, but I can't verify that they added the same PIDs for the Gen 5. I thought they had, but maybe not.Quote:
Originally Posted by Pekka_Perkeles
That would suck not being able to log that when trying to get those curves dialed in.