Torque converter size

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mmzullo

mmzullo

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Hi guys,
My 72 340 duster has a stock torque converter . Here's a little info of my engine. Stock heads, purple shaft cam, 10 to 1 compression,and stock manifold w/holley carb. It dosent like to idle in gear so I need to upgrade my T/C. I built this engine about 20 years ago(dosen't have any miles on it). I've been using it more and drivability is becoming a pain.
My question is a 2000 to 2400 stall converter a good choice? How many inch? Is a stock converter 12 or 13".
Thanks Mike
 
which purple shaft cam?

and where is the timing set.....?
 
Dont remember what cam. This was 20 years ago at least. Was there a street version( I think). I just think it wouldn't make a big difference but it did.
 
mmzullo said:
Hi guys,
My 72 340 duster has a stock torque. Here's a little info of my engine. Stock heads, purple shaft cam, 10 to 1 compression,and stock manifold w/holley carb. It dosent like to idle in gear so I need to upgrade my T/C. I built this engine about 20 years ago(dosen't have any miles on it). I've been using it more and drivability is becoming a pain.
My question is a 2000 to 2400 stall converter a good choice? How many inch? Is a stock converter 12 or 13".
Thanks Mike
Click to expand...

Your converter will be either a 12" or 11" converter. Wide ring gear(about 1") is the 11" converter and the narrow ring gear(about 1/2") is the 12" converter. If it's the converter the car came with when new it will be the 11" unit.
As far as to what stall you want, it depends on a wide variety of conditions(cam diff. ratio, tire size), and what you are using the car for. There have been a lot of posts about converter stall speed with some good and not so good information. Send me a PM.
 
PoisonDart74 said:
Do a search man, you will find "call a quality torque converter manufacturer and ask them" Every time. This question is boring.

www.gopnh.com makes quality stock style converters, 166k and 175k 1900-2100 and 2250-2250RPM respectively, stall included.


Read this:

http://www.hardtail.com/techtips/selectingconverter.html
Click to expand...

What I meant was here we go again, blaming the convertor for what very well could be a tune problem. I may be way off base but even with a damn near all out set on kill motor dropping it in gear and having it crap out due to the convertor being tight is just not going to happen. Years ago I helped a guy with his track car. Motor was a 875 hp 377 SBC. With it's 15:1 CR it would easily idle below 1000 rpm. We were drunk one night and were wondering if the car would even be able to be put in gear with a stock convertor....much to our surprise after a bit of late night wrenching the car could be dropped in gear and have no problem idling....Moral of the story....if an 875 hp motor can idle in gear with a stock "tight" convertor a very mild small block with a cam in it can as well.....
 
I have a 12 inch 2200 in my 360 works great the stock one didnt cut it. Just another opinion.
 
Transman thanks. It was a simple question I think. What size converter in inches was a stock converter. The car is a show car and not a street strip car. The car is all stock except for the cam and carb.
 
70aarcuda. Don't under stand the link? Do you mean look at the distributer? It does have an electronic dist in it already. Pretty sure the advanced curve is correct.
 
mmzullo said:
70aarcuda. Don't under stand the link? Do you mean look at the distributer? It does have an electronic dist in it already. Pretty sure the advanced curve is correct.
Click to expand...

Yes he's suggesting you look at the distributor.

I doubt the advance curve is close to correct.

Here's a simple deal. start car, warm it up. Loosen dist clamp so you can twist it with a little effort. Twist it CCW, if it picked up rpm, you don't have the correct initial timing or advance curve.
 
If your distributor is stock..then the timing is why you engine wants to die went you put it in gear...

you need to increase the initial timing and decrease the mechanical timing from the distributor as shown in the mopar muscle magazine......

it appears that problem comes up here every other day....high performance camshaft...my engine now dies in gear...bla..bla..bla...I need a new torque converter...bla ..bla..bla.....

ok...buy one...but you have not corrected the problem with the timing....
 
Boy you guys are tough in here! This started as a simple question. I'll look at the distributer's advance curve. All my street/drag cars where big block 4 speed cars.
I guess good thing I didn't ask which is better Chevy or Mopar's:banghead:


Thanks for the dist info I'll look into it.
 
Hows that being tough ? You can drop cash on a converter firt if you like but if the timing isnt right its still gonna run like poop
 
Base timing is correct. But if I need to add more I will. I'll check it this week.
 
What is it set to ? 10* is fine for a stock motor but not a modified on. If its got a 484" or 509" purple shaft in it, its gonna want 16* to 20* initial.
 
mmzullo said:
Boy you guys are tough in here! This started as a simple question. I'll look at the distributer's advance curve. All my street/drag cars where big block 4 speed cars.
I guess good thing I didn't ask which is better Chevy or Mopar's:banghead:


Thanks for the dist info I'll look into it.
Click to expand...

The converter is perhaps the single most important purchase you can make. Instead of complaining they are tough, you should thank them for not simply tossing out some stupid generic converter recommendation. These guys givin you advice are a sharp bunch. They can help you a lot. I would listen.
 
mmzullo said:
The car is a show car and not a street strip car. The car is all stock except for the cam and carb.
Click to expand...

That's a wide open statement covered in grey. No matter what the purpose it must function properly. Changing the cam and carb is like a heart transplant. It makes for a whole new engine... Most of the engines you see out there are basilcly a stock engine with a cam and carb change.

Forget about the size (diameter) of the converter. You want to know approx stall speed. While it would be nice to know the exact stall speed, unless you have a dyno sheet to send them to build your custom convertor it will be approx. Follow me..

My frst big block build I called dynamic, faxed them my dyno sheets and they built me a 9" converter that had a 3900 stall speed and it was pretty damn close. You could not tell this car had any special convertor in it under normal operating conditions.

My current car uses an Art Carr 3500 converter. It stalls a bit shy of that. You cannot tell that it had has any special convertor in it.

As said get timing on. I run 14/34 with no vac advance. Once the timing is set, adjust the carb.
 
OP - From what you describe - it sounds liek a tuning problem. It's not stock anymore, so the stock settings for everything need to be ignored. Chances are it's a typical MP 484 or smaller cam and the "10:1" is closer to 9.4 which means you'll need a lot more initial timing than 10°, and will need to reset the carb once the timing (initial and mechanical curves) are optimized. After that - it should idle easilly unde 800rpm, not drop or die when you put it into gear, and pull well with no expense other than time and a few bucks for small parts.
 
While we're have a friendly discussion on converters, I have a 68 Dart, 360/727. It was just rebuilt 1000 miles ago by the previous owner, but for cruise nights with a very mild cam. Stock bottom end, j heads with 202's, stock 340 manifolds edelbrock 1406 600 cfm with a performer rpm intake. Pistons are flat top cast, comp is 9.5. The Lunati voodoo 0701 (256/262, 213/[email protected], 454/475, 112lsa) is being replaced by a Herberts grind 270/280, 215/[email protected], 440/465 on a 112 lsa. The carb will be changed to a 650 thunder, and the manifolds with Schumacher headers. I dont want to change the 3.23 gears. Coan just recommended a Pro Street 11 inch 40215 with a 2500 stall, so I ordered one. Should I put a Trans Go level 2 shift kit in while its in the shop? So far 2 people have said stock is fine "dont mess with it" and 2 said the firmer shifts are worth it and I tend to agree. I also bought a Bouchillion performance kick down cable. Thanks in advance, guys!
 
I looked at the timing yesterday. It was 16 deg at idle and about 50 total without the vacuum advanced. I'll take the dist out and weld and shorten the advance slots. I think I have springs from when I did my dist long time ago.
Thanks for the advice. I'll keep you posted
 
mmzullo said:
I looked at the timing yesterday. It was 16 deg at idle and about 50 total :tongue9:without the vacuum advanced. I'll take the dist out and weld and shorten the advance slots. I think I have springs from when I did my dist long time ago.
Thanks for the advice. I'll keep you posted
Click to expand...

holy timing batman. You had no detonation? Can you imagine what the timing was WITH the vacum advance?

I'd bump that initail up a alittle higher and cut you total to no more than 38.
 
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