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casey
06-08-2005, 09:49 AM
I bought one of those first gear start valve bodies from SASCO and installed in my '64 Lark type. Fun factor went way up. I'd recommend it to anyone thinking about it for their Flight-O-Matic.

Ford valve seals- E7ZZ-6571 A & B; anybody got an opinion on them? I read a recommendation for them in Turning Wheels but the machine shop doing some heads for me insists they won't work. -- you don't have to machine the guides for those do you?

Thanks.

MarkC
06-08-2005, 10:34 AM
Regarding the valve body:

I installed one in my '64 also. What engine and rear axle do you have in yours? My car is a 259 with the 3:07 rear end. I found that the light throttle upshifts and trailing throttle downshifts were too high after I installed the valve body. I didn't mind the high upshifts, but the downshifts were too abrupt and I felt they might cause damage over the long term. (The downshifts occurred at about 20 mph for the 3-2 and 15 for the 2-1.) I ended up changing the governor to the one used in the V8 taxi models, and that lowered the trailing throttle downshifts to about 15 mph and 10 mph, respectively. I think that anyone with the 3:31 or taller axle ratio might not even consider it an issue, but with the 3:07, I did. I didn't think so initially, but now that I have a tach in the car, I feel the 3:07 is a good choice for today's driving. And, the first gear start makes up for the taller ratio. I'll also add that properly adjusting the throttle pressure linkage on the transmission is crucial for proper operation of any Flightomatic. Lastly, the valve body I installed had obviously been on the shelf for some time and a couple of the shift valves were stuck. I recommend anyone obtaining one of these bodies carefully clean and verify that the valves are free. (Mine wouldn't shift when first installed, so I had to take it out, clean it, and reinstall.)

Take care and best regards.

Mark

MarkC, 64 Y8
Working in Spokane, WA

casey
06-08-2005, 12:06 PM
Mark- My engine is a fresh 289 and rear end is 3.31 Dana 44 TT. I'm glad you brought up the issue of shift speeds. I shift from 1st to 2nd at roughtly 17-18 mph, and then from 2nd to 3rd almost immediately at about 22-23 mph. Seems to me I should be in 2nd over a larger range. I've only had it in for a week and intend to take it back to shop to see if they can adjust that linkage for a higher shift to 3rd. My downshift to 2nd is almost unnoticeable, and downshift to 1st is at about 10mph and doesn't seem that dramatic, although in city driving I could where it would add more wear and tear.

When the mechanic first put it in he jumped in for a test ride and it shifted from 1st to reverse- then he called me in a panic. Turns out you have to let it fully pressurize and 'loosen up' before you drive it- so anyone installing one should keep that in mind.

and Mark- I don't what you mean by governor- is this something they put on the carb linkage?

Roscomacaw
06-08-2005, 12:51 PM
casey, the governor he talks about is part of the transmission. It fits into the tailhousing of the tranny and there are different ones for different application transmissions.;)

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

MarkC
06-08-2005, 01:42 PM
Casey,

It sounds like the throttle pressure linkage on the transmission may need adjustment so that the the 2-3 upshift will delay as the throttle is depressed. There is a procedure in the service manual that I highly recommend owners comply with. This will not only affect part throttle upshifts, but will assure a proper forced downshift if the throttle is floored.

These transmission are not terribly sophisticated, but are quite durable if cared for. Very basically, an engine driven pump supplies main line pressure to the valve body when the engine is running. This pressure is fed to a governor at the rear of the transmission that sends the valve body line pressure that varies by vehicle speed. What happens in the valve body is the line pressure from the main pump (high at all times) forces a shift valve against a spring, thereby keeping the transmission in whatever gear it is at the moment (as the proper servo is activated). As vehicle speed increases, governor pressure increases on the other side of the valve until, at a given speed, the pressure is the same on both sides of the valve. The spring then moves the valve and the transmission shifts (by activating other servos). Controlled by vehicle speed only, this would happen at predetermined vehicle speeds as dictated by the governor. (These are mentioned in the service manual.) The pressure sent to the shift valves is also modulated by another valve connected to the throttle linkage. When adjusted properly, increased depression of the throttle will delay the governors control over the shift valves until higher vehicle speeds are reached. (Of course, there is more going on than this, but you get the idea.)

So, the throttle linkage adjustment is very important. Without the electronic enhancements of modern automatics, you don't have as much to work with to improve drivability. You have to take advantage of whatever adjustments are available. Aside from the linkage adjustment, the governors can be replaced (with some caveats) and axle ratios can be changed.

Take care,

Mark

MarkC, 64 Y8
Working in Spokane, WA

casey
06-08-2005, 02:34 PM
Mark- Thank you for the enlightenment on the governor vs. valve body. Believe it or not, this '64 is first automatic I've ever owned. And I've been driving since '72.

When I took the car in to get the valve body installed I gave the mechanic my shop manual and marked the page that had the section on adjusting the linkage. I just need to get him to 'revisit' that part.