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727 converter questions

KozmicKuda

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I was lucky enough to buy a 69 Charger about 6 weeks ago. Owner died of a heart attack in April. It's pretty much been in storage since 1997 when he bought it. It came with a stack of papers and receipts from 1988 to 1997. One of them is an undated receipt from a local well known HD trans shop where it lists a "prostreet" trans rebuild, prostreet converter, trans cooler, Direct Connection reverse pattern valve body 3.23 SG install.
Engine is a "rebuilt" 383 and it obviously has a lumpy cam, headers, Weiand single plane and 650 Holley DP. I have no idea of cam specs, CR or engine internals. The widow told me the previous owner was turning it into a race car so some of the interior is gone like the console and floor shift, along with the heater/A/C box.
I drove it 6-7 miles from the storage garage to here using the Roadkill red plastic gas can behind the grille. Since then I installed a new stock gas tank, sending unit and replaced all the rubber lines with new. So now I can actually drive it more than 5 miles at a time.
I took it out one time after maybe 1.5 miles in total. When cold it takes a LOT of throttle just to get it to move. It slips so much I was worried about burning up the trans. As it warms up the behavior improves and is actual drivable. Just making laps around the neighborhood I didn't get on it much because the car is L-O-U-D and I don't want to piss off the neighbors. It sounds like open headers but there is an H pipe with small bullets with turndowns. People hear it coming and stop what they're doing to stare, it's that loud.
All of this is not my style as I actually like to drive my cars. I go out of state to big shows all the time so eventually the 383 will be tamed down. Milder cam, dual plane, vacuum carb and a tighter converter. I can live with the manual valve body.
Questions:
1. What was the stall speed of the converters used in late 60s HP 383s and 440s? A little higher stall speed would be ok with me.
2. I've been looking for tighter converters on Marketplace, an old stock one for instance. I did find a deal on a new Hughes 24Fuel. Website says 1200 stall and it sounds like it's optimized for towing and gas mileage. Is that workable for the short term?
I want something tighter than what I have so the car is more streetable. Cam and induction changes are definitely going to happen but I'll most likely drive it as is in the spring to local shows.
It's winter here and it's not getting out of the 20s today.
One more thing, I don't want to spend a lot of money for a custom converter as I have a new Tremec 5 speed laying around the may eventually find its way into the car.
 
you don't want that 24 fuel converter it will bang into gear plus it will be a real dog. get 383 HP 11 inch stock converter or something like it with a 2000-2200 stall. even a stock 440 12 inch is 1600-1700 rpms
 
1967-1977 318/383/440 engines all with a steel crank had a 12" (narrow ring gear) converter in it from the factory. Stall speed 1900/2200 stall, and they had no weights on them. The 11" (wide ring gear), was used from 1973-1976 with a forged crank. From 1977-up they had another converter. Stall speeds on all of them 1900-2200. The differences my catalog shows between the 73-76 and the 77-up converters, was in the weights on the converters.
 
1967-1977 318/383/440 engines all with a steel crank had a 12" (narrow ring gear) converter in it from the factory. Stall speed 1900/2200 stall, and they had no weights on them. The 11" (wide ring gear), was used from 1973-1976 with a forged crank. From 1977-up they had another converter. Stall speeds on all of them 1900-2200. The differences my catalog shows between the 73-76 and the 77-up converters, was in the weights on the converters.
the 11 inch converter was out before 1973 with the 340 and 383 hp in the super bee and road runner in 68 - 72. 12 inch was never 1900-2200
 
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the 11 inch converter was out before 1973 with the 340 and 383 hp in the super bee and road runner in 68 72. 12 inch was never 1900-2200
I am well aware of the 340 11" converter that came out in 1969. That being said though, my catalog, the one I used when I worked in the industry, shows that the 12" converter was the one used with the steel crank 318, 383 and 400 engines from 1967 to 1977. These converters had no weights on them. Our part number on it was 359, and the stall on it, depending on which engine was in front of it, was 1900-2200 rpm. The listings my catalog has for the 11" (wide ring gear) converter big blocks shows up starting in 1973 and had either had two small weights on them, or one large butterfly weight. The HEMI converter was by itself of course, and at our facility, all HEMI converters were core in first. Catalogs of course can be wrong, but I did own at one time a 69 383 Road Runner, and it had the 12" factory converter in it.
 
I am well aware of the 340 11" converter that came out in 1969. That being said though, my catalog, the one I used when I worked in the industry, shows that the 12" converter was the one used with the steel crank 318, 383 and 400 engines from 1967 to 1977. These converters had no weights on them. Our part number on it was 359, and the stall on it, depending on which engine was in front of it, was 1900-2200 rpm. The listings my catalog has for the 11" (wide ring gear) converter big blocks shows up starting in 1973 and had either had two small weights on them, or one large butterfly weight. The HEMI converter was by itself of course, and at our facility, all HEMI converters were core in first. Catalogs of course can be wrong, but I did own at one time a 69 383 Road Runner, and it had the 12" factory converter in it.
what catalog are you looking at ?
 
Your catalog is wrong, the 383HP had the same 2801764 11" converter as the 340. The 383-2 had the 12" converter.

If you had a '69 383 RR with a 12" converter, somebody changed it.
 
I am well aware of the 340 11" converter that came out in 1969. That being said though, my catalog, the one I used when I worked in the industry, shows that the 12" converter was the one used with the steel crank 318, 383 and 400 engines from 1967 to 1977. These converters had no weights on them. Our part number on it was 359, and the stall on it, depending on which engine was in front of it, was 1900-2200 rpm. The listings my catalog has for the 11" (wide ring gear) converter big blocks shows up starting in 1973 and had either had two small weights on them, or one large butterfly weight. The HEMI converter was by itself of course, and at our facility, all HEMI converters were core in first. Catalogs of course can be wrong, but I did own at one time a 69 383 Road Runner, and it had the 12" factory converter in it.
do your homework and get back with me. :)
 
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If its slipping cold and gets better warm there could be a broken ring on the pump stator or another issue. Switching convertors may not fix it.
 
The converter in my barracuda will occasionally lose it's fluid....draining back into the trans (I think). Then when you try to make it move it barely moves. In a couple minutes of running time it feels normal. It's an 8 inch Coan.
Actually I don't know if this drain back is caused by the converter or something in the trans.
 
I recently rebuilt a 1970 727 that decoded to being from 1970 383 H.P., in a Cuda/Challenger. The 11" (wide ring gear) torque converter with it was dated 7/69, and had 2600 stamped on it, which I assume is the stall speed.
A low stall converter like you mentioned would not work well with the "built" 383 you mentioned. It will pull the rpm's way down when shifted into gear, and will result in low manifold vacuum as well.
 
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Slipping worse when cold could be converter drainback. Try running the engine for 10 seconds or so in Neutral (not Park ) before putting it into gear.
 
The converter in my barracuda will occasionally lose it's fluid....draining back into the trans (I think). Then when you try to make it move it barely moves. In a couple minutes of running time it feels normal. It's an 8 inch Coan.
Actually I don't know if this drain back is caused by the converter or something in the trans.
Converter drainback is kinda normal with Torqueflites that are not driven every day. When these cars were new, and used daily, a small amount of drainback was not noticeable from one day to the next. Now, when our treasures may sit for many days between use, the converter drains enough fluid back into the transmission, that it can not operate as it should. I shift my car into NEUTRAL before starting it, and then let it run for 30 seconds or so to refill the torque converter. This condition is more noticeable in REVERSE, because this circuit requires about 3 X the fluid pressure as forward circuits. The converter will NOT refill while in PARK, so shift to NEUTRAL.
 
do your homework and get back with me. :)
I will trust the factory parts book over any aftermarket catalog.

In the factory book notice that the 383Hp and 340 use the same 764 11" converter while the 383-2 and the 440 use the same 586 12" converter

TC.PNG
 
Chrysler never put a high stall converter behind 440's, figuring they had enough low rpm. torque that it did not need it. I put an 11" on the 440 in my '67 R/T, and like it.
 
I will trust the factory parts book over any aftermarket catalog.

In the factory book notice that the 383Hp and 340 use the same 764 11" converter while the 383-2 and the 440 use the same 586 12" converter

View attachment 1777823

Interesting that they used the same converter behind a 318 and a 440, although it would behave differently due to the higher torque output of a 440…
 
Chrysler never put a high stall converter behind 440's, figuring they had enough low rpm. torque that it did not need it.

Actually, they did use the 764 converter behind the 440HP starting in the '73 model year. The standard performance 440 retained the 586 converter from previous years.
 
Best converter I had in my A12 (its stock, except for rmvb) was a stock 73 340 converter. Stalls a very nice 25-2600 behind a stock 440.
O.p., is your garbage converter a GER?

(And get rid of the bullets. I like Flowmaster sound, but only the three chamber ones, or any Quality turbo or hemi muffler)
 
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