Wietse
Well-Known Member
Hey guys,
Need some advice from the transmission experts over here!
I had some reads about 727 overhauls and potential upgrades on the forum.
Planning next winter to pull the tranny out and do a full dismantle, inspection and rebuild.
The transmission sits in an "early" '69 Coronet R/T with a 440 HP engine.
The engine has a 4-barrel Holley 770 carb, Eddy Performer RPM intake and Hughes Engines HE3844BL cam with 238/244 @ .050" and .572/.576" lift....no idea about the horse power but i guess it will be in the 425-ish area. ??
Currently installed torque converter has a 3000-3200 flash stall, other then that i have no details of it.
It does seem a little bit of "tight" converter as it does engage quite strong in idle and makes the engine take quite a drop in rpm due to the load.
I am planning a new torque converter anyway with a similar stall but a little more "loose".
Transmission numbers on the pan rail are as follows: 2892093L 2534 9032
which is for the 440 HP and should be build date 5th June 1968
So according my home work i am able to upgrade the valve body with a "part throttle kick down" attachment and has a 24-spline input shaft.
I am not planning to have/use any manual controls, i just want it to run in auto with good shifts and have the part throttle kick down give the option to allow the 3-2 down shift without the need of hammering the pedal on the floor if i need a quick overtake or so.
The car is a streeter/cruiser with the random traffic light fun and will not see any track/strip action.
My ideas are this:
1) Unless i find severe wear or damage i am not planning on replacing anything else than all friction materials and seals.
I don't think i should need to buy more stronger material for high High horsepower applications, suggestions welcome in this.
Planning on using the A&A kit MK22000A, which seems to be the standard kit with red clutches and regular steels.
http://www.aandatrans.com/Products/...s-and-Regular-Steels-(1962-70)__MK22000A.aspx
Forward and Low/Reverse band need to be purchased separate, but there are a few too many choices here to "just take a pick".
I have no idea on what to pick, again i don't know if i should select something for higher hp applications or not?
2) I also want to add the "Part Throttle Kick down" which is a direct bolt-on to the valve body.
A&A sells the upgrade kit for this. Part number: 22740-32SI
http://www.aandatrans.com/Products/727-3-2-Kick-Down-Module-(1966-69)__22740-32SI.aspx
3) Install a shift kit for those firmer shifts.
A&A shift kits: AATF-1 Mild Shift improver kit OR AATF-2 Street/Strip OR HD Shift kit.
AATF-1:http://www.aandatrans.com/Products/727904-Mild-Shift-improver-Kit__AATF-1.aspx
AATF-2: http://www.aandatrans.com/Products/727904-StreetStrip-Race-or-Heavy-Duty-Shift-Kit__AATF-2.aspx
4) Change out the governor.
My car originally had a 3.23 standard rear axle but now has a 4.10 ratio installed. (it has a LSD but i am not sure original or aftermarket, 489 case)
So because of this IMO the governor pressure is actually not "calibrated" with the road speed as it sees a lot more centrifugal force due to the low gearing.
A&A has several governors to choose from, but i don't know what to select from here to reach the correct setup as i am not sure if the rear gearing change on my car affects the functioning.
So this leaves me a bit in doubt on the overhaul kit friction materials and bands.
What is wise to select for this application, anyone any experience?
Regarding the shift improvement kit i am leaning towards the AATF-2 kit for HD application, the Mild improvement kit sounds a little "mild" lol.
The PTK upgrade is pretty straight forward.
Regarding the governor kit i would say a shift point of 5800 is ok with me, but what does that do to the governor pressure compared to the stock application that is in there now?
Should i select a higher or lower number to compensate or something?
For a new torque converter i was thinking about an A&A 10" Street competition, 3000/3400 stall.
But my most driven speed on long stretches will be 50mph, which puts the engine at 2650rpm with this driveline, so i don't know if it is wise to have the stall speed on the converter quite a bit higher than the cruising speed....guess not.
Does it help to go for a larger or smaller torque converter in diameter and have a lower stall speed? How does that work out?
Because i guess with a too high stall converter it will not only become a fuel hog but also keep the temperatures high on the tranny. (I have already upgraded with an additional oil cooler)
What about the sprag? It might be in good condition, but is it worth replacing with a new one while i am in there?
I am hoping some of you could chime in with some experience on the above details.
A&A website is not giving any details about their parts and kits.
Thx for reading and any info is welcome!
Need some advice from the transmission experts over here!
I had some reads about 727 overhauls and potential upgrades on the forum.
Planning next winter to pull the tranny out and do a full dismantle, inspection and rebuild.
The transmission sits in an "early" '69 Coronet R/T with a 440 HP engine.
The engine has a 4-barrel Holley 770 carb, Eddy Performer RPM intake and Hughes Engines HE3844BL cam with 238/244 @ .050" and .572/.576" lift....no idea about the horse power but i guess it will be in the 425-ish area. ??
Currently installed torque converter has a 3000-3200 flash stall, other then that i have no details of it.
It does seem a little bit of "tight" converter as it does engage quite strong in idle and makes the engine take quite a drop in rpm due to the load.
I am planning a new torque converter anyway with a similar stall but a little more "loose".
Transmission numbers on the pan rail are as follows: 2892093L 2534 9032
which is for the 440 HP and should be build date 5th June 1968
So according my home work i am able to upgrade the valve body with a "part throttle kick down" attachment and has a 24-spline input shaft.
I am not planning to have/use any manual controls, i just want it to run in auto with good shifts and have the part throttle kick down give the option to allow the 3-2 down shift without the need of hammering the pedal on the floor if i need a quick overtake or so.
The car is a streeter/cruiser with the random traffic light fun and will not see any track/strip action.
My ideas are this:
1) Unless i find severe wear or damage i am not planning on replacing anything else than all friction materials and seals.
I don't think i should need to buy more stronger material for high High horsepower applications, suggestions welcome in this.
Planning on using the A&A kit MK22000A, which seems to be the standard kit with red clutches and regular steels.
http://www.aandatrans.com/Products/...s-and-Regular-Steels-(1962-70)__MK22000A.aspx
Forward and Low/Reverse band need to be purchased separate, but there are a few too many choices here to "just take a pick".
I have no idea on what to pick, again i don't know if i should select something for higher hp applications or not?
2) I also want to add the "Part Throttle Kick down" which is a direct bolt-on to the valve body.
A&A sells the upgrade kit for this. Part number: 22740-32SI
http://www.aandatrans.com/Products/727-3-2-Kick-Down-Module-(1966-69)__22740-32SI.aspx
3) Install a shift kit for those firmer shifts.
A&A shift kits: AATF-1 Mild Shift improver kit OR AATF-2 Street/Strip OR HD Shift kit.
AATF-1:http://www.aandatrans.com/Products/727904-Mild-Shift-improver-Kit__AATF-1.aspx
AATF-2: http://www.aandatrans.com/Products/727904-StreetStrip-Race-or-Heavy-Duty-Shift-Kit__AATF-2.aspx
4) Change out the governor.
My car originally had a 3.23 standard rear axle but now has a 4.10 ratio installed. (it has a LSD but i am not sure original or aftermarket, 489 case)
So because of this IMO the governor pressure is actually not "calibrated" with the road speed as it sees a lot more centrifugal force due to the low gearing.
A&A has several governors to choose from, but i don't know what to select from here to reach the correct setup as i am not sure if the rear gearing change on my car affects the functioning.
So this leaves me a bit in doubt on the overhaul kit friction materials and bands.
What is wise to select for this application, anyone any experience?
Regarding the shift improvement kit i am leaning towards the AATF-2 kit for HD application, the Mild improvement kit sounds a little "mild" lol.
The PTK upgrade is pretty straight forward.
Regarding the governor kit i would say a shift point of 5800 is ok with me, but what does that do to the governor pressure compared to the stock application that is in there now?
Should i select a higher or lower number to compensate or something?
For a new torque converter i was thinking about an A&A 10" Street competition, 3000/3400 stall.
But my most driven speed on long stretches will be 50mph, which puts the engine at 2650rpm with this driveline, so i don't know if it is wise to have the stall speed on the converter quite a bit higher than the cruising speed....guess not.
Does it help to go for a larger or smaller torque converter in diameter and have a lower stall speed? How does that work out?
Because i guess with a too high stall converter it will not only become a fuel hog but also keep the temperatures high on the tranny. (I have already upgraded with an additional oil cooler)
What about the sprag? It might be in good condition, but is it worth replacing with a new one while i am in there?
I am hoping some of you could chime in with some experience on the above details.
A&A website is not giving any details about their parts and kits.
Thx for reading and any info is welcome!
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