What determines shift point on TH400?

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Aug 4, 2004 | 08:05 PM

T-Top Tom 1

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What determines shift point on TH400?

On a 1974 TH400 what determines shift point on WOT? Mine is shifting around 4000 rpm. What needs changed? Thanks for any info.

Aug 4, 2004 | 09:38 PM

clem zahrobsky

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From: delmont pa

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Quote:

Originally Posted by T-Top Tom 1

On a 1974 TH400 what determines shift point on WOT? Mine is shifting around 4000 rpm. What needs changed? Thanks for any info.

the governor controls WOT shifts. you can drill holes in the weights and/or change the springs

Aug 4, 2004 | 11:43 PM

Big Fish

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I could be wrong, but I thought the governer was kind of a "fail safe" that would cause an upshift before the engine would over-rev (I thought usually around 5500 RPM) and the modulator is what is supposed to cause an upshift based on vacuum. It does sound like your governer is having problems though.

Aug 5, 2004 | 01:21 AM

enforcer

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From: corryton tn

B and M used to sell a kit to changed the weights and or springs in the govenor. It was real easy to do and got my shifts where I wanted them. You might find a similiar kit elsewhere.

Aug 5, 2004 | 02:28 AM

BSeery

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Quote:

Originally Posted by enforcer

B and M used to sell a kit to changed the weights and or springs in the govenor. It was real easy to do and got my shifts where I wanted them. You might find a similiar kit elsewhere.

They still do.

Aug 5, 2004 | 06:06 AM

Larry B.

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From: Orlando Floriduh

If the kickdown solenoid doesn't work, somehow it will shift earlier than it does on the detent. I am not sure why but I have had a couple of th400's do that.

Aug 5, 2004 | 07:27 AM

NHvette

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Matt Gruber had a nice post on this - specifically the governor
calibration kit/install/adjustments. I searched for it - but not in
the archives anymore. Maybe it will be resurrected later.

I remember he cut a hole in the trans tunnel and put a plate
over it, so the governor could be removed from inside the car.