Adjusting Modulator
Thread Starter
Racer
Joined: Jul 2004
Posts: 400
Likes: 1
From: California
Adjusting Modulator
i work at napa and bought one of the adjustable red striped modulators for the th-350 on my 79 vette. does anyone know which way i turn it to bring my shift points down int he rpm range? or can someone explain to me the details of how it works? i just bought it so i could adjust it so im not 100% sure how to work it.
thanks in advance!
thanks in advance!
Le Mans Master
Joined: May 2002
Posts: 5,084
Likes: 786
From: Lebanon Township New Jersey
I had my TH350 trans redone and it has a red striped modulator on it. I lowered my shift point about 300 rpm by turning the small screw inside 1/4 turn clockwise. Hope that helps.
Instructor
Joined: Dec 2005
Posts: 196
Likes: 0
From: Burlington WI
I used to rebuilt automatics in the 70's & early 80's and I would turn the
screw in or clockwise for higher shift points and out for lower shift points. Lower vacume rises the rpm shift and higher vacume lowers the
rpm shift. The mod. works in operation for the upshifts along with
the governor. But the governor works the downshifts by over riding the
mod pressures.
screw in or clockwise for higher shift points and out for lower shift points. Lower vacume rises the rpm shift and higher vacume lowers the
rpm shift. The mod. works in operation for the upshifts along with
the governor. But the governor works the downshifts by over riding the
mod pressures.
Instructor
Joined: Dec 2005
Posts: 196
Likes: 0
From: Burlington WI
Not sure what the napa one that you have got. but the ones I used
to have you used a very small straight blade screwdriver, like the little
ones snap-on used as there promotions years ago. Thats been some
years back. It should not have a valve core as the vac. as to change
in order to change to pressures in the trans.
to have you used a very small straight blade screwdriver, like the little
ones snap-on used as there promotions years ago. Thats been some
years back. It should not have a valve core as the vac. as to change
in order to change to pressures in the trans.
