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TH 400 Problem Maybe?

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Old Aug 2, 2009 | 03:27 PM
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Default TH 400 Problem Maybe?

Heres the jist of things.

91 Camaro Z28
383 Stroker
TH400
B&M 2400 Convertor
3600 GVW Cooler.

The trans shifted fine with my old motor (406) no problems what so ever. The car shifted on its own at about 2500 or so casually driving.

Dropped in my 383 and now the trans shifts at 4000 from first to second, 3500 from second to third. I just drained and refilled the tranny last night, it is full. The trans fluid doesnt smell burnt. The car will shift from park to reverse, drive 1st, 2nd 3rd with no issues at a stand still. The car drives fine, and shifts decently firm on the 1 to 2 shift, minus the 4000 shift point.

Im almost thinking the motor has something to do with it, but am not sure.

Any help would be appreciated.
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Old Aug 2, 2009 | 06:10 PM
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Anyone?
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Old Aug 2, 2009 | 06:14 PM
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Check that you have good engine vaccume to the modulator ?
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Old Aug 2, 2009 | 07:16 PM
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i would think that maybe you have a different vacumm signal from different motors and cam profile high vacumm low shift points, low vacumm higher shift points.....with same governor setup ....the modulator is adjustable though or you may have to play with the governor...but as frank saids make sure the vacumm is hooked up sounds like its not
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Old Aug 3, 2009 | 03:43 AM
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Went over the vacuum lines and found one that had a slice in it. Replaced it and all is good. Thanks.
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Old Aug 3, 2009 | 08:14 AM
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Cool glad could help
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