Thread: Converter stall question ?!?!

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I'm almost ready to do my planned engine swap in my 1967 Plymouth Belvedere II. I'm switching out the original (very tired 121,000 mile) 318, for an ex-police HP 318 with 360 heads and a forged crank. I'm Doing the typical up grades to the car along with the engine swap, double roller timing chain, new water pump, new oil pump and shaft, long tube headers, Tranny cooler, and so on and so on. I'm also changing out the cam to a Comp Cams 262H cam.

Here are the specs on the cam:
* Advertised duration: 262 intake/270 exhaust
* Duration at .050 in. cam lift: 218 intake/224 exhaust
* Gross valve lift: .462 in. intake/.470 in. exhaust
* Lobe separation: 110 degrees
* RPM range: 1,300 to 5,600
* Noticeable idle, works with 3.23-3.55 gears (I have a 3:23 Sure Grip in the car now)

I know that this is a fairly mild cam by most performance standards, but the car is a daily driver, and I wanted a performance increase without a bunch of "comfort" loss. A close friend of mine is recommending a Mopar #4876879AB 2400 - 2500 stall converter. Now I'm not anywhere near as versed in this area as my friend is, and it's not that I don't think he knows what he's doing. But it seems to me that the stall range will be a little high for the cams RPM range, especially for a "daily driver" !?!? Mopar offers two other converters with lower stall ranges, #4876870AB 1900 - 2100 and #4876878 2250 - 2350.

I'd like to hear your thoughts on what you would do with this combination, if you need any other info on the car to make a decision, just ask.

Thanks in advance,

- Mr. B

I had a 2,800 stall in my panel truck It had a 454 - 400 turbo. I actually wish I had put a higher stall in it. To get a good hole shot I had to let it idle on the line and then jam on the gas when the light turned green to sorta' ramp up on the stall. If I power braked, it would boog off the line. Lil' too much engine for the set up maybe. It was a budget operation at the time.
As far as being streetable, it was fine. I drove it from Iowa to the nats. in Columbus (2 - 8 hour days of driving each way.) and I was pulling a pop up camper ta' boot. No heating problems at all. Had a cooler in front of the radiator (not not running through the radiator).
2,800 didn't act a whole lot different to me than a stock converter. I would think 2400-2500 would be no problem. Rear end gears will have some bearing on it too. I was running 4:10, so I was running around 3,000 RPM on the Hwy.

Try going to sleep after listening to a 454 @ 3,000 RPM for 8 hrs.
May bee' that's why I don' hear so goooood, no more???

I dont think it would be too much of a problem myself but remember that the actual stall speed is based on the TQ that the motor is putting out so even though its advertized as say 2800 stall it may have a different range behind your combination.

Originally posted by BlownGoat
I dont think it would be too much of a problem myself but remember that the actual stall speed is based on the TQ that the motor is putting out so even though its advertized as say 2800 stall it may have a different range behind your combination.

That's true, Blowngoat.
Other than talkin' to a few reps. at shows, I haven't thought too much about a converter for the new project yet. Some say too high = too much slippage and heat for the street. Others say just put a big cooler on it and go for the high stall 3,500 -4,000. Dunno,..... I don't have to decide for quite awhile.

Just re read my reply Pro when i said 2800 rpm i meant 2500rpm in response to Mr.B ....but i had your 2800 in my head and didnt mean to sound like i was questioning the combo you had in your panel truck


Have you given much thought about the converter your gonna stick behind the Z's blower motor? my motor shop said they will give my specs to a shop to have them build a converter for me but i guess its gonna be alot lower stall than i was thinkin (around 3500) he said blowers like a lower stall than other combos....guess i'll believe him since its my first blower attempt

Originally posted by BlownGoat
Just re read my reply Pro when i said 2800 rpm i meant 2500rpm in response to Mr.B ....but i had your 2800 in my head and didnt mean to sound like i was questioning the combo you had in your panel truck


Have you given much thought about the converter your gonna stick behind the Z's blower motor? my motor shop said they will give my specs to a shop to have them build a converter for me but i guess its gonna be alot lower stall than i was thinkin (around 3500) he said blowers like a lower stall than other combos....guess i'll believe him since its my first blower attempt

I was a little disappointed in the 2,800 I had in the panel. Don't want to go too low with the "Z". 3500 sounds like it would be right in the "Boost" range. My only concern with high stall is the heat build up, but they say coolers these days are better, and not to worry about it. I didn't have a trans brake back in those days. I had a guy talk me into a selonoid that tapped into the valve body. That was a long time ago, but if I remember right, you took one of the check valves out of the valve body and this seloniod took it's place. Then you could control the stall with a switch??? Kind of a poor mans transbrake I guess..... It Never Worked. We're talkin' 30 years ago. When you said "trans. brake" back then you really meant "trans break". HEHEHE I'll probably wait to see where my engine combo and rear gears end up and then decide how crazy to go with the converter. Cours' ya' know I'll go conservative.......HEHEHEHE...