Ozz1967

iTrader: (4)

I should have installed a new one on my 84 T/A when I had the engine out for the swap but I was hoping all would be good and trying to save some money. But now that it's all together, the car wants to die when in gear with the idle set to 900rpm. I've bumped the idle to 1100 but that's just a short term fix I hope. Is it even possible to swap torque converters with the trans and engine in the car or do I need to pull one or the other to do it? Any input would be greatly appreciated. Thanks!

Apeiron

You need to separate the transmission from the engine, but you don't need to completely remove it. I'd be surprised if the converter was your problem though.

Ozz1967

iTrader: (4)

Well, I had it to a very reputable shop here to do the exhaust and had him double and triple check everything I did. He went through and completely cleaned up my engine bay, re-accomplished a bunch of connectors that had done as well as re-checked my timing and hooked up my A/C. When he test drove it he said the cam I got was too big for my stall converter because when the idle was set to 900 I lost alot of vacuum (and I do, my brakes hardly work when it's idling), and it studders and wants to die. Sometimes I have to feather the gas to keep it running. At highway speeds it runs fine (other than runnign hot). He said that really the only way to fix that would be to install a better torque converter (22-2500 or so). ANy thoughts?

Engine mods:
Lunati Cam (Summit part number 60121)
Scat rotating assembly
World Sportsman II Heads
Hyper pistons
Comp Cams Pro-magnum roller rockers
3.73 rear gears
Stock tranny (rebuilt with B&M trans kit in it)

Apeiron

Ok, that makes more sense. You need a new converter (it's not a "stall converter") with a higher stall because right now the engine doesn't make any power at low RPM because of the cam. The higher stall will allow the engine to skip over the low RPMS and immediately start making power.

That's unrelated to your idle speed issue though.

Ozz1967

iTrader: (4)

I've heard them referred to as one in the same many times. I think you are the first person I've come across that's specified one way or the other. So having the car want to die at low RPM's wouldn't be related to having the wrong "size" converter in it?

Apeiron

I've heard it lots of times too, but it's still just as wrong. There's no such thing as a "stall converter" as in "something that converts stall". It's a "high-stall converter", as in "a converter with high stall".

No, the car stalling at low speed isn't related to the converter at all. If you have a large cam, you just can't get the engine to idle at a factory speed no matter what you do.

Are you settomg your idle speed by the factory tach?

zippy

A higher stall speed converter will help an engine with a high duration/low LSA camshaft idle better due to less load at lower rpm. It won't likely be the fix for your problem though. You may want to find a way to add more ignition timing at an idle. Getting the timing to around 26-30º or so of timing at idle will help alot.

Ozz1967

iTrader: (4)

Yes I'm using the factory tach. I checked the tach against a sunpro tach that a friend of mine is putting in his truck...the factory tach isn't off by more than 50-100 rpm.

Ozz1967

iTrader: (4)

What will that be without the computer plugged in? Right now mine is set to 12* initial without the computer plugged in, no idea what that is with it in. I don't want to run too much because I don't want to get into detonation.

Apeiron

The stall speed of even a stock converter is far enough above the minimum idle of all but the very nastiest of cams that it won't change the idle load significantly.

Fast 383

iTrader: (2)

Actually, it's a "Torque Converter," as in "something that multiplies torque"