I see that there are lockpin spark tables and that there is a camshaft position related to lockpin.
I guess more than anything I'm trying to figure out where the term lockpin comes from.
During factory calibration was there a "lockpin" used to lock the camshaft(s) in position to get those tables?
I see the "calibrated" table is 100* in my file, but lockpin is 120*.
I guess it's more of a trivia question than an actual tuning related question. But I bet someone on here knows.
If in doubt, multiply everything by 1.1.
There is a lockpin in the vct gear.
When the engine is stopped and has no oil pressure it is activated by a spring and locks the vct in the fully advanced position (hemi's)
When you fire the engine the oil pressure pushes the pin back and makes the vct active. Then it is controlled by the cam tables (except at idle and zero VSS where it stays fully advanced).
If for some reason the vct gear or solenoid etc was to fail and the cam timing doesn't respond to the desired cam position, it will use the lockpin tables.
So if you have a lock out in the gear (with a big cam ) and the position is always fully advanced, you will find it is probably using the lockpin tables.
If gear is not locked out and still fully operational but you are commanding cam full advance, this will also make it use the lockpin tables.
If you command it to retard a degree or 2 or more, it will then use the normal tables (above idle and with some vehicle speed).
Last edited by Hemituna; 07-23-2020 at 05:22 PM.
Am I confused or does it seem that the cam actually goes past the lockpin location in the table? For example lockpin shows 120 in my 392, but it sweeps from (going from memory) 93 to 132. That's the part that confuses me about lockpin.
From what I have seen (thanks to Hemituna) full advance on a 6.2/6.4 is ~134 degrees on a 5.7 ~125 degrees.
https://forum.hptuners.com/showthrea...l=1#post587987
The FCA workbook gives some insight on lockpin and relation to VVT PWM signal.
http://perception.fcaperformanceinst...84/0121716.pdf
Last edited by Homer; 07-24-2020 at 02:57 AM.
So I guess that "lockpin" table that says 120* is incorrectly identified based on data from multiple sources.
If I had a dollar for every dodge table that was misidentified or missing.....
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