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bluey
November 1st, 2013, 08:54 PM
Hi
I have fitted a 4.3l V6 from a 2005 Chevy astro into a 1945 army jeep. the astro was an auto but I have fitted a manual gearbox.
I have been able to work out most things from searching the forum and have the jeep running fairly good.

The only problem I have not been able to fix is, if revved over 2500 rpm when I depress the clutch to change gears the revs hang.
I have played with the throttle cracker in gear and it is better but I am not sure I am on the right track.
I also enabled and set up DFCO but this didn't change the hanging.

so couple of questions - am I on the right track playing with the TC

Do I need to add an input into PCM to tell it I am in gear

Or do I need to add a clutch input.
I have attached my tune file


Thanks Darren

hog
November 2nd, 2013, 05:23 AM
Have you tried a 4.3 manual transmission calibration? There shold be plenty of 4.3/manual transmission calibrations around.

Do you have a VSS(Vehicle Speed Sensor) input to the PCM? That input is what tells the "brain" how fast the vehicle is moving and what it should tell teh engine to do.

peace
Hog

bluey
November 2nd, 2013, 08:41 AM
Thanks Hog

Yes I do have vss connected.
I do have some manual tunes for the 4.3 but when comparing them to the tune I am using I can't see any difference that I thought would make a difference.

ScarabEpic22
November 2nd, 2013, 09:18 AM
Just because there arent any visible differences doesnt mean there arent differences. There are ALWAYS differences between an auto and manual calibration. Im assuming since it's an 05 engine that it's a 1MB LS1B PCM, shouldnt be hard to find a 4.3L/manual OS and full flash it like hog suggested.