Torque converter

polara383500

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Looking to upgrade the converter! I have a stock one in now but need a 2500 to 3000 stall! Looking at ones online for at ones for a tf727 some have the flywheel attached and some they don’t! Mine is converter and flywheel together. What’s the diff between the two?
 
Your torque converter interfaces with the crankshaft flange via a "flex plate", which does not have the starter ring gear atached to it, as the flex plate is not round or that big in diameter. Which is why the starter ring gear is a part of the torque converter.

What cam? What mechanical compression ratio? What rear axle ratio? What tire size? Is the car going to be regularly driven on the street? Size of automatic trans cooler?

Enjoy!
CBODY67
 
If you can find an oem 10” it will stall in that range.
 
Your torque converter interfaces with the crankshaft flange via a "flex plate", which does not have the starter ring gear atached to it, as the flex plate is not round or that big in diameter. Which is why the starter ring gear is a part of the torque converter.

What cam? What mechanical compression ratio? What rear axle ratio? What tire size? Is the car going to be regularly driven on the street? Size of automatic trans cooler?

Enjoy!
CBODY67
I have the purple shaft.474 and 355 gears! I have 18” rims tire size is 27”
 
IF I understand correctly, in Mopar-speak, "10 inch converter" = 10.75" diameter converter, with "11 inch converter" being 11.75" diameter? Whereas in "Brand X-speak", "10 inch converter" means a converter of 10" diameter.

FWIW,
CBODY67
 
IF I understand correctly, in Mopar-speak, "10 inch converter" = 10.75" diameter converter, with "11 inch converter" being 11.75" diameter? Whereas in "Brand X-speak", "10 inch converter" means a converter of 10" diameter.

FWIW,
CBODY67
So I should go with a TCI 11” or Hughes 11”
 
No real need for an aftermarket converter when the 10.75" Chrysler converter was on lots of OEM production vehicles, including my '70 383/330 Monaco. In the Chrysler Reman catalog, it also used to be spec'd for '68 Road Runner 383/335 and slant 6s. Probably many 440/375 cars, too. Seems like it was also referred to as "Street HEMI" converter, too?

KEY thing is that it loads the engine less at idle and lets the engine rev free'r until it gets tighter. Stall speeds are tossed around a bit too much, by observation. A converter that stalls at 1800rpm behind a 383-2bbl will stall higher when its behind a 440/350, just because there's more power in front of the converter. Conversely, a converter that stalls at 2800rpm behind a 440 will stall at lower rpms when behind a 383-2bbl.

Additionally, if you read the factory-spec stall speeds in the 1978 Chrylser service manual, you'd suspect they were building race motors although the stock motors (400s and 440s) were low-compression motors. Many were in the 2800-3000rpm range! From the factory!

Unless you need that TCI or Hughes decal on the car for contingency money if you win at the drag strip, I suspect that a quality reman unit could do just as well, if you get the one for the correct OEM application. Which could be "Street HEMI", considering the camshaft you have. Whether you need the balance weights on the converter or not will depend upon what's in the motor that can make it "internal" or "external" balance.

Just some thoughts,
CBODY67
 
Read the operating range of you cam spec's. The 11" convertor is more durable, the 10" is more lively. If the cam specs are for 2500-6000rpms you need a stall speed in the 2500 range. Keep in mind that this is relative depending on what gear ratio you are running and the peak torque range of the cam. If this is for a street engine it would be best to error on the low side as you fuel mileage will drop like a rock if you go more than a 2500rpm stall speed.

Dave
 
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My 2 cents is to find a Hemi torque converter and have it rebuilt to match the specs and weight of your car. I had Ultimate Converters do a Hemi converter for my '68 Sport Fury with the stock appearing 520" and couldn't be happier with it. Not sure if Ultimate Converters is still around as I know that one of the owners, Lenny, retired. My recall is that they are in SC.
 
The biggest issue is I don’t have the cam spec card! I bought the cam off a buddy for 50$ that they used in a 440 build but on the dyno the guy wanted more horsepower so they pulled it out!
 
The biggest issue is I don’t have the cam spec card! I bought the cam off a buddy for 50$ that they used in a 440 build but on the dyno the guy wanted more horsepower so they pulled it out!
In the absence of a cam card, you can measure the lobe heights x rocker arm ratio to get the advertised lift of the cam. If you have an old short block laying around gathering dust, you can get a crankshaft degree wheel, a magnetic dial indicator, a lifter and pushrod, some wire to verify TDC, chuck it all together and measure the lobe lift and duration via the pushrod. Of course, you'll also need a "lying in wait" timing chain set, too.

Chart ALL lift from about .010" lobe lift to max lift for the intake and exhaust. That's how I discovered that on a normal cam, "max lift" happens for only 1 degree of crank rotation, whereas the assymetrical CompCams "max lift" happens for a full 10 degrees of crank rotation (using an old NOS HiEnergy 268 that I was going to use in a NOS 440 motorhome block a good while back). Of course, that lift data would include the duration at .050", too.

Usually, on non-Pontiac and non-Nailhead Buick cams, the max lift is an indicator of the cam's duration. As a general guide.

Just some thoughts,
CBODY67
 
Another choice would be to look at the cam itself, most will have the cam number or the duration/lift stamped on the rear of the last bearing journal. The cam number can be looked up on line to get the specs.

Dave
 
The old big converts are a 091. The smaller converter is a 764. This is Chrysler’s terminology. U also will need the matching flex plate. Talk to a converter company. It’s one of the best upgrades u can do to your car. Ultimate, PTC, Dynamic are good places. Kim
 
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