Classic Mustangs (Tech)Technical discussions about the Mustangs of yester-year.
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Vehicle: 1967 Ford Mustang Coupe, '09 Warriors In Pink
Location: Smyrna, TN
It attaches from vacuum provided by the intake down to the rear of the transmission and attaches to the vacuum modulator. It has rubber hoses at both ends, the modulator end normally has a 90* rubber hose which is usually dry rotted and leaking as it's not easy to see and is normally never changed in 40+ yrs. which causes an unknown to find vacuum leak on many cars. If the metal line just has surface rust you could brush off the rust with some steel wool and give it a coat of paint or clear. If it's pitted then change it as it may have pin hole leaks. If there is fluid (trans) coming out of the vac. modulator it needs to be changed also.
The vacuum line connected allows the transmission to shift in synch with engine RPM.
"If it isn't broke I haven't fixed it yet" - Jon
'67 Coupe 289>333, AOD, CandyApple Red/red dlx interior, fox seats, 9" 3.50.
'09 Warriors in Pink w/glass roof - wife's Mustang
Jon, that was a real good description right up to the point where you said, "The vacuum line connected allows the transmission to shift in synch with engine RPM."
The vacuum modulator controls part throttle shifts depending on the load on the engine - seperately from rpm. Under light throttle (high vacuum) you could shift into 3rd at or before you reach 20 mph while under harder acceleration it might not shift to third until 40 or more mph. The governor will shift the transmission at around 4800 rpm if the load is high enough (low vacuum) that the modulator is still not shifting.
Other than that you did a great job!
66 Muskrat coupe 351 W Toploader
O.k. thanks for the information. However I don't see any rubber lines. I have a 65 inline 6 and it just screws into place along the lines of how your brake lines would screw into the master cylinder. I am talking about the correct part?
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