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I concur with PontiacJim. Continental used to provide what was called "The Jim Hand Converter". The reason was that Jim Hand used it in his 4200 pound station wagon. He got it into the mid 11's with a 455 that used factory parts. IIRC it is a 13" that flash stalls to about 3000, but it is tight under light loads. The last owner of Continental died and if it is still in business it would be under a different name. The old address and phone numbers were 730 Centinela Ave, Inglewood CA 310-674-1072. Be aware that stall speeds are proportional to engine torque. One that stalls at 3000 in a 455 would stall at about 2300 in a 350.

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As is the case so often in this field, the OP has been given conflicting advice. The last thing I want to do is create an argument nor disrespect anybody's opinion in any way.
I'm going to clarify my opinion and reasons why so that others may make informed decisions.
When I say "driveablity issues" with high stall converters, I don't mean it doesn't work or there are performance issues. I'm using that term in the "retail car repair world" meaning. I'm talking the "feel" of it.The OP doesn't have a heavy station wagon that he wants to run 11's with. Yeah, tall gears, tiny converter, that's a hot drag setup. How's it around town? I have a lot of hours behind the wheel of cars with high stall converters in everyday driving, not by choice. Yeah, still fast, but not enjoyable. Not that the 2500 we're discussing here is high stall, but the concept is the same.
You're cruising around town, anytime you get off the gas and unload the trans, which in your heavy car with tall gears you do a lot, when you get back on the gas, you have to spin that converter back up.
It's not a great feel.
Most people who drive a mucsle car around on the street want the feel of your right foot is directly connected to the rear wheels....a big V8 with short gears.
That's the feel most people want.
Which brings me to the advice I really want to stress.
Before you spend a cent, you need to soul search what you really do or want to do with the car.
If you need the car to go 100 on the highway, then you want the gears you have. The only way you're getting it off the line is with a higher stall converter so that's the way to go.
If you drive like most, you're probably on surface streets going 35-65 the bulk of the time. In that circumstance? No question, lower gears, "regular" converter is the way to go.
Drag racer? You're getting both so save up.
I would not put 3.42 or 3.55. Too much.
You put 3.23's in there with a stock converter and you will have the muscle car you want.
 

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Your opinion counts Mine's and you are not offending anyone. I think if you had driven a "tight" converter, you may understand. I get what you are saying. But, I also feel you are speaking of higher powered cars and higher stall converters. I also understand, as what we used to to in our youth, was the high stall high slip converters in small block Chevy's that spun 8,000 RPM's. The high stall converter didn't really move the car until you hit the pedal and RPM's came up to 2,500 or so RPM's and it moved. Always knew these cars because the engine was racing and the car wasn't moving very fast - inspite of the 4.11 and 4.56 gears they had. They were also needed because the big cam idled much higher and with the stock converter you would have to keep your foot on the brake to keep the car from rolling - if it did not stall out.

The "tight" converter in my brother's 360 has a difference of 200 RPM's from letting off the gas, like coasting, to applying pedal pressure to get the car moving part throttle. You do not mash the pedal down while cruising. If you take off from a stop, it does not zing up to 2,500 before moving. If you put it to the floor, then indeed the converter will spike right up to 2,500 RPM. That is the design of a "tight" converter, less slip at moderate pedal pressure but has the capabilities to zing right up to 2,500 RPM's and put the engine in its lower power band.

Maybe "stall" is the wrong term here? Maybe I should be using "flash stall." A torque converter’s flash stall is typically the most accurate rating, versus a footbrake stall that is dependent upon too many variables like brake type, pad/shoe conditons, tire size, engine torque, etc..

Here is a quote from Hughes Performance for reference that may help, " There are three common methods to gauge the stall speed characteristics of a torque converter. Footbrake stall is the maximum amount of engine RPM that can be achieved in a forward operating range with the brakes fully applied to prevent the vehicle from moving forward. Footbrake stall is not an accurate method of determining the true maximum stall speed of a torque converter. Furthermore, advertised stall speed ratings are not based on footbrake stall speed. Maximum static stall is the maximum amount of engine RPM that can be achieved in a forward operating range without generating any driveshaft motion. Maximum static stall can only be verified in a transbrake-equipped vehicle. Flash stall is the amount of engine RPM (or flash) that is observed upon initial acceleration under load. The easiest method for checking flash stall is to drive the vehicle at low speed in second or third range and immediately transition to wide open throttle. The RPM level that the engine immediately accelerates to is the flash stall. Flash stall speed is one of the most useful ways to truly gauge the stall speed characteristics of a torque converter and how those characteristics will influence the acceleration potential of a vehicle. "

From another website on transmissions, "When choosing the stall speed that is right for your application, a rule of thumb is that the advertised stall speed will need to be at least 500 rpm higher than the beginning of the camshaft’s powerband. All aftermarket camshafts are delivered with a recommended RPM operating range. If your camshaft has an operating range of 1,500 through 6,500, you would select a torque with a minimum of 2,000 rpm stall. If choosing a torque converter for use in a street car, you might want to select a torque converter with a stall speed that is below the engine RPM at 70 mph, since this is where your engine will spend a lot of its time. "

I know that my brother's 360 cam is rated for 2,000-6,000 RPM's, so his converter of 2,500 RPM stall fits with the above statement. But again, with the "tight" converter having much less slippage than a "loose" converter, flash stall of 2,500 RPM's for the converter may be the better description?

Looking at gear swap, yep, more accleration, but raises the RPM. Pulled up a calculator just to plug in some numbers for a comparison. Using a 27" tire/automatic trans - 2.78 @ 55 = 1,974 RPM's, 70 = 2,487 RPM. 3.55 gear @ 55 = 2,495 RPM, 70 = 3,175 RPM. My opinion. I am not comfortable cruising longer distances at 70 MPH @ 3,175 RPM's. Keeping up with 75 MPH traffic on the highway (which is average here in Charlotte) puts the RPM at 3,402. But if I were driving local roads and they averaged 45 MPH, then with 3.55's the RPM would be 2,041 which would be great and car would be very responsive and be a good choice to drag race down the avenue where short full bore blasts would be made and not steady high speeds like on the highway.

Now if I went with 3.55's, then a flash stall of 2,000 RPM's may be far better? But now you are talking near stock torque converter stall and going aftermarket may be a bad investment as you are not really gaining much versus cost/time invested.

Not being arguementive, just my experiences. There is more than one way to skin a cat and it is always hard to juggle finances and get your best bank for your buck and hope you made the correct choice - even I do a lot of second guessing. And with a stock 170 HP 360 and A/C in the 4,000 + pound Fury, gas mileage won't be had even if I had an 1,800 RPM converter. The 2,500 stall gets it moving far more snappier with the 2.71 gears and aids in passing gear when I snap it to the floor. LOL The big block cars having more torque did indeed get the lower stall converters as stock.

If the decision is to go with a converter, then contacting a converter specialist or custom builder and providing all the needed info that they will require is the best way to get the correct converter for the application. (y)
 

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Thanks you all for putting all this info in one thread I can save. All this info I've read before but not in one place. Thanks to the OP for starting this thread, much good info for him to consider.
 

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I currently have the stock 8.2 rear with 2.78 gears. If I change gears I think I'm going for 3.42s or 3.55s. That would require a carrier, gears, rebuild kit, fluid, etc. Costs looking like 850+ for decent parts alone. Also looking to do it myself to save some cash.

The converters looking like it would be half that cost right now..
Be careful. One thing you want to avoid is if the car ever sees highway use is having the converter still be "in stall range" when you're at cruising rpm on the highway. That means it'll still be slipping some and that can cause your transmission fluid to overheat.
 

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Discussion Starter #26
Thanks all for the input and discussion. I agree that there is a lot of good info to consider.

I have been looking at a COA-20211-4 Coan converter based on Coans suggestions. This is a 2400-2600rpm Bb chevy stall. I'm sure I'll be on the lower side of that stall, but that will be fine

I've been curious about trans health in general so I checked line pressures. I wanted to be sure before adding a new converter. Got good readings with max pressure in low and second being 145psi or so.

I also tried to get a better feel for my stock stall. I stabbed the throttle at 20-25mph in second gear and got 1700rpms or so. It was difficult to tell too much before it kicked down.
 

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That's about right for the factory stall. I have always read it is a bout 1800, so with a little less torque from the 350, you are in the ball park for factory.

If you go with the converter, let us know your opinion on it.
 
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