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Discussion Starter #1
Have a 69 Mustang FB with a 302 and C4 tranny. Prior to parking it for the winter I noticed it was taking longer than usual to shift in drive. First shift was about 10 mph and second shift was at about 20 to 25 mph. Before parking it the the first shift was still at 10 mph and the second shift was now at about 35 mph. Over the winter I had put a Stage 2 shift kit and a new modulator valve in.(A buddy said my shifting problem was the modulator valve)Took the car out for the first time today and now the car still shifts for the first time at 10 mph but now the second shift is at 40 to 45 mph. My question is - Is the modulator valve adjustable? I still had the old one and noticed there is something that resembles a adjustment screw on the vaccum hose side. If it is adjustable, which way should I adjust the screw? ALSO before I had parked the car, when I would shift into 1st (low) gear it would catch at about 15 mph; now I am just about at a full stop when I can feel it shift to low. Other than these two shifting problems the tranny shifts smooth and great; no slipping and great take off power. Any suggestions? Thanks


<font size=-1>[ This Message was edited by: stang69sk on 4/21/02 12:52pm ]</font>

<font size=-1>[ This Message was edited by: stang69sk on 4/21/02 1:01pm ]</font>
 

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Adjusting the modulator screw in clockwise will raise the shift points and turning it out will lower them.
What shift kit did you fit??
 

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Discussion Starter #3
The shift kit I installed was a B&M shift Improver kit. Used the stage that required a 3/16" hole to be drilled in the valve body plate. I had also installed a Torker 289 intake and a Edelbrock 600 cfm carb with a mild cam and a Ford Electronic Ignition; Would part of my problem be vaccum? I am going to adjust the modulator valve and I will let you know. Thanks Darrell
 

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Discussion Starter #4
Just adjusted the modulator valve and did not seem to make much of a difference. Excuse my stupidity, but when you say turn the screw clockwise to raise the shift point do you mean it will shift at a lower RPM or at a higher RPM. I had adjusted the screw counterclockwise about 1 1/2 turns thinking this would make it shift at a lower RPM but I think it is now shifting at a slightly higher RPM. Also I noticed when I went to adjust the valve the vaccum hose on the valve itself slipped of very easily. When I put it back on it does not seem to be very tight. Could this may be part of my problem. I have taken vaccum readings at the intake and it is running between 10hg and 19hg on different RPM ranges. Thanks Again Darrell
 

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Darrell, Turning the modulator screw in (clockwise) will make the shift points higher, meaning it will shift later.Turning it out it should shift sooner,but either way it won't make too much difference. Make sure the hose going to the modulator fits tight at the modulator and at the other end where it gets vacuum from the manifold.It could be just a loose connection or a cracked hose which is hard to see sometimes.
 

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Discussion Starter #6
Finally got a chance to get under the car. The hose was very weak, I had replaced it and also adjusted both bands. The Intermediate to 1 1/2 (was just about 2 1/2) and the low to 3 turns(which it was). I am sill having problems with the shifting but with a new twist. Driving the car now the 1-2 shift is perfect; when easing on the gas it is smooth and when hammering it is hard and crisp. The 2 - 3 shift is a different story. When cold (even after 15 minutes) It does not shift until 45 to 50 mph when easing on it. When hammering it will shift about 35 mph and it actually spins the rear wheel abit. After it is warm it will shift at about 30 mph under normal gas and when pushing it, it will shift around 30 mph (hard and crisp). So right now cruising around or a little above the speed limit the engine is turning around 1900 rpm in town in stead of around 1300 rpm. I also notice now when cruising after it has completed the 1 - 2 shift you can feel the whole car lag like it is trying to shift. After it completes the 2 - 3 shift you can faintly feel the laging continue. Would this be from me tightening the bands? Kinda mystified on this one. Any suggestions
 
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