Why do I want a higher stall TC?

[vtwinsport]

Hey all,
Why would I want a higher stall torque converter? And, what does that mean "stall".
I know this may obvious to others but I've never had it explained. Considering an upgrade as my tech shop advises a higher stall TC with new cam and heads coming.
Thanks in advance

[Keith Seymore]

"Stall" is when you smash your foot on the gas, and smash your foot on the brake and note where your engine rpm ends up (like 2500, or 3000 rpm, or whatever).

(...assuming the brakes hold!)

You want a higher stall mostly for racing or brisk street driving, since it will get your engine rpms up into the power band sooner. This would be important if you are going to a cam or intake/carb combination that doesn't like low rpms.


K

[joe231]

yeah what Keith said.
If you power is up high and you have a factory stall it will be gut-less off the line.

[dv8customs]

Detailed explanation from TCI's website

http://www.tciauto.com/Products/Tech..._explained.asp

[3r!c84]

what about just if your going 60 at like 2200 rpm will the converter lock up or will it be slipping becuse its a high stall(i never realy got this??)

[68 TT]

Originally Posted by 3r!c84

what about just if your going 60 at like 2200 rpm will the converter lock up or will it be slipping becuse its a high stall(i never realy got this??)

If you have a lock up type torque converter it will, if not the trans will be slipping a little at that speed. It will still move just not as efficiently as a lower stall would at the same RPM.

This is where a lock up type converter really works the best. You can have the high stall to get you moving quicker but have the cruise efficiency when it locks up.

Drag racers even use them with multiple lock up clutches to gain top end MPH and eliminate slip. I had a five clutch lock up converter in my 86 Grand National that was built to be locked up at full throttle.

[78 Chevyrado]

If you get a high stall TC make sure to get a big Tranny cooler if you drive it regularly. Slipping= heat It won't hurt it, just make it a lil hotter all the time under the stall speed.

[68Timber]

Do you know what cam is going in or the specs? I hate to hear that you don't know what you need, the cam will dictate exactly what stall speed you need. You can run up to a Comp 268 which is pretty healthy for a street driven truck with the stock converter. But 68 TT is spot on, if you put any converter in with a higher stall speed you will want to install an aftermarket tranny cooler in front of the radiator. It's not expensive, hard, or time-consuming, but it will dissipate the heat created by a higher stall convertor and keep that tranny running good.

You really need to know the cam specs first to know what convertor you need. The cam might really wake up your truck and turn it into a beast. But with a mismatched converter (too high stall speed) the truck will be a slug and you'll be disappointed.

[qu1cks1lver56]

I've thought about putting a little higher stall converter on my truck just so I'm not fighting it with the brakes at a red light.

[Chlsnk]

http://www.starperf.com/index.php?p=...36017&parent=0 This is the cam going in my current engine build (358cid taken .40 over) I was told a 2200-2800 stall would be golden for me. Is this true?

[78 Chevyrado]

Originally Posted by qu1cks1lver56

I've thought about putting a little higher stall converter on my truck just so I'm not fighting it with the brakes at a red light.

A higher stall will cut the need for the "gas pedal two step". I had that in my mustang I used to have and I finally got a consevative 2500 stall and while it wasn't quite a big enough stall for that car, it did cut out playing with the gas at a redlight.

[3r!c84]

ok how do a lock up converter work?
and will it work with a higher stall tc?

[qu1cks1lver56]

Originally Posted by 78 Chevyrado

A higher stall will cut the need for the "gas pedal two step". I had that in my mustang I used to have and I finally got a consevative 2500 stall and while it wasn't quite a big enough stall for that car, it did cut out playing with the gas at a redlight.

Yeah I have to do that sometimes, gets on my nerves. Some days it seems worse than others, I guess it's the goofy ass FL weather.

[78 Chevyrado]

Originally Posted by 3r!c84

ok how do a lock up converter work?
and will it work with a higher stall tc?

a lockup converter will "lock up" at steady cruising speeds like on a highway. It has an actual clutch in the TC.

ALL automatic transmissions slip some at any and every speed, period. What the lockup converters to is make a physical lockup between the trans and engine, like a manual tranny. It's a gas mileage thing. It cut all slip out, but only under low load conditions.

If you ever drove something, say a 4 speed OD tranny, it will actually sound slike a 5 speed at times. You go through all 4 gears, and then the RPMS drop again when the TC locks up. OEM they are electronically controlled, but many aftermarket vendors make 700r4's and 4l60's that have a mechanical lockup, meaning it will work without electronics. I've never driven one with the mechanical setup but the electronis ones work well.

[78 Chevyrado]

Originally Posted by qu1cks1lver56

Yeah I have to do that sometimes, gets on my nerves. Some days it seems worse than others, I guess it's the goofy ass FL weather.

Yeah Luckily i didn't have to drive that thing in stop-n-go traffic much. I'd have done something about it if I would have had to. As much as I had to play with the pedal, I might as well have had a manual and just set the idle to whatever it needed to not stall out.

[qu1cks1lver56]

Originally Posted by 78 Chevyrado

a lockup converter will "lock up" at steady cruising speeds like on a highway. It has an actual clutch in the TC.

ALL automatic transmissions slip some at any and every speed, period. What the lockup converters to is make a physical lockup between the trans and engine, like a manual tranny. It's a gas mileage thing. It cut all slip out, but only under low load conditions.

If you ever drove something, say a 4 speed OD tranny, it will actually sound slike a 5 speed at times. You go through all 4 gears, and then the RPMS drop again when the TC locks up. OEM they are electronically controlled, but many aftermarket vendors make 700r4's and 4l60's that have a mechanical lockup, meaning it will work without electronics. I've never driven one with the mechanical setup but the electronis ones work well.

and the lockup makes better gas mileage? They make 'em for TH350's?

[slugish]

Originally Posted by BRUISER

Do you know what cam is going in or the specs? I hate to hear that you don't know what you need, the cam will dictate exactly what stall speed you need. You can run up to a Comp 268 which is pretty healthy for a street driven truck with the stock converter. But 68 TT is spot on, if you put any converter in with a higher stall speed you will want to install an aftermarket tranny cooler in front of the radiator. It's not expensive, hard, or time-consuming, but it will dissipate the heat created by a higher stall convertor and keep that tranny running good.

You really need to know the cam specs first to know what convertor you need. The cam might really wake up your truck and turn it into a beast. But with a mismatched converter (too high stall speed) the truck will be a slug and you'll be disappointed.

What is the duration on a 268 cam -- Does it vary from manufactureer to another or is it standard-- the reason Iask Idont knowe what cam Ihave . but Ido know its got 224-230 duration with a 048 lift with 1.5 rockers. Its a comp. cam . My stall is shot , but tranny shifts fine . Iwould like to know what stall converter is best for me or do Ineed any at all . Iknow right now that Ican't get any rpms in my power band without the tires spinning with the shot converter Ihave

[78 Chevyrado]

Originally Posted by qu1cks1lver56

and the lockup makes better gas mileage? They make 'em for TH350's?

I don't think they make any for a TH350. It would either have to have electrical or mechanical provisions inside the trayys to operate.

[78 Chevyrado]

Originally Posted by slugish

What is the duration on a 268 cam -- Does it vary from manufactureer to another or is it standard-- the reason Iask Idont knowe what cam Ihave . but Ido know its got 224-230 duration with a 048 lift with 1.5 rockers. Its a comp. cam . My stall is shot , but tranny shifts fine . Iwould like to know what stall converter is best for me or do Ineed any at all . Iknow right now that Ican't get any rpms in my power band without the tires spinning with the shot converter Ihave

What size engine?
What tranny?
What rear gear?
what diameter are the tires?
how much does the truck weigh?

[qu1cks1lver56]

Originally Posted by 78 Chevyrado

I don't think they make any for a TH350. It would either have to have electrical or mechanical provisions inside the trayys to operate.

There's never anything cool for a TH350

[joe231]

there are TH350C transmissions that have lock up converters....

[vtwinsport]

Hey guys, thanks for all the input (ha - no pun intended).
Yes, I don't have a budget nor the inclination for a 700r transplant so I'm sticking with the t350.

Bruiser- Truck has stock 350/ t350 with edelbrock carb, intake and headers with 3.08 rear gears (being changed to 3.42 in the spring), dart iron eagle 67 heads coming (now stock 76cc), comp XE 268 cam is in the garage waiting for spring. Stock converter as far as I know in the transmission.
I have the carb and timing tuned as fine as I can (including jets and springs) and I often have to shift into neutral or peddle the gas to keep from stalling at stop llights with current converter.

What I want is more snort from the line- 1000 rpm to 3000 rpm really and I daily drive this with periodic hwy travels in a week. This will never see the strip and there is a factory trans cooler in my rad already. Is that stock one good enough?
Thanks in advance

[tonyscustomrides]

ya there is lock up torque converters for the th350, my 81 silverado swb has one from factory. the previous owner wired a manual switch to turn it on and it drops the rpms like 200. i go 70 mph rite around 2100 rpms.

[qu1cks1lver56]

Wonder where to find one.

[3r!c84]

yours probly has it and you dont even notice ,like mine i dont feel it get into lock up but i can feel it unlock when i floor it at like 60(where it wont down shift) you feel it slip for a sec and then goo!