727 transmission rebuild Q's
 

hi i have a 1970 Charger with a 440 and a 727 transmission that just gave up. i was wondering what i should have done to the transmission to better accomidate the 440s output.

Is the 440 built up at all? What goodies are on it?

A shift kit, stall convertor (depending on the power of the 440), and a really good rebuild kit installed by someone who knows mopars really well will do you wonders.

the charger
 

oh ok cool sounds good. is there any parts brands that are recomended? its a 440 bored out 60 over and has a edlbrock perfromer intake with a 4 barel carb that is a double pumper. i have all aluminum pulleys, water pump and water pume housing, mopar performance cam for mid to high performance, the heads were rebuilt.

As far as I am concerned, B&M is the best (parts wise) for mopar trannies. For new trannies, I would only go with TCI.

Is this the kind of kit you are referring to: http://www.bmracing.com/s.nl/c.72308...it.A/id.354/.f

I think with what I am doing to my 440 I have to identify any possible weak links so I would like some more info on the stock 727 trans.

a stock 727 torqeflite in good shape can handle 450 h.p. with no porblem.
a good shift kit can really help it out. also think a bout a good torque converter with a stall of around 2300 or 2400 . this will really help out on acceleration .

for in city driving and strip that would be a good stall speed, but if your planning on taking the car onto the highway, then I would look for a little lower stall rating. probably 2000 to 2200 RPM.

what is the stock stall rating?

I think they range from 500 to 750 RPM. Put your car in gear when its running and have it on a flat area. Let your foot off the brake and see at what RPM you start moving. That is where the torque convertor is kicking in and having the tranny move the vehicle.

So I started looking at converters and TCI seems to be a popular brand and their Saturday Night Special seems to do what I want, anyone have any opinions on them?

I also noticed that they sell ones with weights on them which they say are used to balance the cast crankshaft, but I replaced the 1977 cast crank with a 1973 (I think) forged one (steel), so do I go for the unweighted stall converter? Are these cranks balanced on the flexplate or not at all?

The picture on their website shows teeth on the converter where as Summit shows it needing a flex plate, anyone have the answer to that?

if you replaced the cast crank with a steel one, you would have had to change the balancer and the torque converter or you would have had a badly out of balnce motor. a cast crank motor is balanced with the balancer and the t. converter installed, the steel crank motors were internally balanced with just the crank, pistons and rods. now if you have a torque converter that is not weighted ( for a steel crank internally balanced motor) it can be used on a externally balanced cast crank motor by using a b&m flex plate with the cutout , ( a small half moon shaped section cut out of the plate).

all mopar torque converters i have seen have the teeth for the starter on them. the flex plate is only for connecting the engine to the t.c.

I have not done anything yet, the engine is still sitting in the machine shop waiting to be picked up.

I am trying to figure stuff like this out before it becomes an issue, so I need to get a regular flex plate as I will be using a non-weighted stall converter? TCI has two different types of flexplates ones with 5/16 bolts and ones with 7/16 bolts, I assume this for the crank?

A better way of checking for the stall of the convertor is to put it in gear, put your foot on the brakes and then nail the throttle for a second. The max RPM you see on your tach before the car starts pulling is around the stall. They are designated to be the point where the engine torque overpowers the fluid and begins transferring the energy to the transmission. The more torque your engine makes, the higher the stall will be, even if it's factory rated at say 2200 rpm. If you're driving normally, it won't "flash" to the stall point, it will start pulling sooner than that. It's sorta like a clutch... if you feather a clutch in, it will start grabbing at a lower rpm than if you rev the engine and just dump it. The stall effect is like dumping it.