77 th350
Thread Starter
Intermediate
Joined: Nov 2010
Posts: 44
Likes: 0
77 th350
Need help as to hooking up vacuum from modulator to engine. has holley 4160 carb and not sure if it goes directly to manifold or not. Trans works great but does not shift into 3rd. Adj cable new linkage any ideas are great> THANKS
Last edited by Acesone; Nov 11, 2011 at 10:32 AM. Reason: Error
Melting Slicks
Joined: Oct 2002
Posts: 2,317
Likes: 111
From: St Louis MO
The vacuum modulator at the transmission should be connected to a port on the intake manifold. The port is often in the top of the runner going to the #8 cylinder and has a fitting or tee to connect a short length of vacuum hose to a 1/4" OD line going to the transmission vac modulator.
If no vacuum is supplied to the modulator, shifts will be as firm and as late as they would be at WOT since this is how the trans senses the load on the engine - i.e., zero vacuum in the intake manifold is full throttle!
If no vacuum is supplied to the modulator, shifts will be as firm and as late as they would be at WOT since this is how the trans senses the load on the engine - i.e., zero vacuum in the intake manifold is full throttle!
Last edited by larrywalk; Nov 11, 2011 at 11:19 AM.
