Choosing a stall speed.

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darter

darter

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I have a 70 Dart 340.Comp. cam 256 int.--268 exhaust Part # 20-221-3. 3.55 gears 727 trans -LD 340 intake with thermoquad carb. I had the front bushing in the trans replaced and the place I had it done replaced the converter .
at the same time. I believe it was stock from a 360.Not sure why at the time but since then the car has really bad low end pulling power.From a dead stop it doesn"t pull well but has lots of power midrange and top end.I just want some advice on a good quality,reasonably priced converter.
 
I don,t think they would,ve put a 360 converter in it(external balanced)with your 340 being internally balanced.They might,ve put a 318 converter in it?You should be able to order a 2500 stall from your local trans shop.Converter Man is in the Toronto area.I had a 2500 stall from him behind a 360...worked great.

Oh,welcome to FABO.
 
Have one custom built for your combo, from a place like Turbo Action or ATI. it may cost a little more but you will be happier in the end. Those off the shelf converters, like B&M don't always do what there advertised to do ( stall wise). Just my opinion though...
 
What's your engine got for initial timing? Check that, I'll guess it should be in the 14-18 range. If not, that will cause it to be sluggish down low.

As far as a converter, a decent TRUE 2500 converter would work well behind that engine. They have have swapped out a higher stall for lower stall when the swap was made = bad...
 
I personally had the people at Dynamic transmission pick my convertor stall speed when they built my transmission. Knowing you're in a different boat and not knowing exactly what you're running for a trans whether stock or not is hard to evaluate the stall in my opinion. I would never bring my transmission to a normal trans shop in the first place..
 
darter said:
I have a 70 Dart 340.Comp. cam 256 int.--268 exhaust Part # 20-221-3. 3.55 gears 727 trans -LD 340 intake with thermoquad carb. I had the front bushing in the trans replaced and the place I had it done replaced the converter .
at the same time. I believe it was stock from a 360.Not sure why at the time but since then the car has really bad low end pulling power.From a dead stop it doesn"t pull well but has lots of power midrange and top end.I just want some advice on a good quality,reasonably priced converter.
Click to expand...
If they replaced your converter,ask for your old one back.Also why did they change it in the first place:dontknow:?Sounds alittle shadey to me.JMO
 
Yep listen to Pettybluedart, go demand your old convertor back. They replaced your factory 340 higherstall with a low stall boat anchor. If they give you a hard time put a complaint in with better the businness burreau. Why would a shop charge you and install an inferior convertor?? Scam?
 
Any of you conspiracy theorists ever think that maybe the old converter was scored up too bad to reuse? Because the OP said the bushing needed to be replaced. The bushing is in direct contact with the converter. Make sense to me. I had 727 that I pulled from a car & the bushing went bad & ate the converter snout all up. Everybody is so quick to scream rip-off any more! It probably did need a converter & they put 1 in that was available.
 
was the old converter an aftermarket one? That could cause a big change. If they went from the factory 10.75 to a factory 11.75 then that as well will knock off about 400 rpm of stall. Check you brake stall, hold your brakes hard and see where the converter revs to steady on the gas. Factory should be 2250-2450 rpm on a 70 340. If it's stalling 1800-2000 then it's probably got a 11.75 converter from an early 70's 360. you might be able to see in the inspection cover how much of the starter ring gear is exposed compared to the converter bell then compare it to pictures of factory 11.75 and 10.75 converters. It's also possible its stalling even lower with a bad converter so check where it is stalling now.
Either way you probably want an aftermarket converter which I guess is what you asked for in the original post! Sorry.
 
All my factory 340 converters were 3000 stall They brake stalled at 2500 -2800 Depending on how stout the motor was . I have two left here on the shelf. The factory performance converters all had drain plugs. The later truck 727's were 2500 stalled at 2200 on most no drain plug. easy way to tell if your oringinal performance converter is still there. Steve
 
The 2250-2450 brake stall I listed is out of the 1970 service manual. If its factory and stalling much more then that most likely the transmission is slipping (again at least according to the service manual). The other possibility would be the motor has been modified and making more power then stock. The 1970 340 converter has part number 2801764 the exact same part number as the 1970 225, 318, and 383-4 with a 727. In 1970 at least every 10.75 inch converter was the "high stall".
 
Lonewolf3165 said:
Any of you conspiracy theorists ever think that maybe the old converter was scored up too bad to reuse? Because the OP said the bushing needed to be replaced. The bushing is in direct contact with the converter. Make sense to me. I had 727 that I pulled from a car & the bushing went bad & ate the converter snout all up. Everybody is so quick to scream rip-off any more! It probably did need a converter & they put 1 in that was available.
Click to expand...
I,ve had a snout crack on my Coan 4500 stall and had the snout replaced,not the whole convertor.Just sayin..More info is needed here from the original poster.
 
darter said:
I have a 70 Dart 340.Comp. cam 256 int.--268 exhaust Part # 20-221-3. 3.55 gears 727 trans -LD 340 intake with thermoquad carb. I had the front bushing in the trans replaced and the place I had it done replaced the converter .
at the same time. I believe it was stock from a 360.Not sure why at the time but since then the car has really bad low end pulling power.From a dead stop it doesn"t pull well but has lots of power midrange and top end.I just want some advice on a good quality,reasonably priced converter.
Click to expand...

I just got Dynamic converter back the other day. Had to send it back for a restall for new motor. That cost me $450. I think a new one would running you around $600.
 
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