Ovr_Cst: Torque Converter

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Sifrino3

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I see alot of people going to 3000 Torque Converters. But I don't know if I want it that high. I want to beable to drive it up to 80mph with out the rpms being up there. There is no rpm gauge. So, I will not be able to tell. So, I ask you this. Whats best for Street/hwy. Not street/strip.

Thanks,
Ramsey
 
unstoppable said:
The converter doesnt change your cruising RPM whatsoever.
Click to expand...

So, how does that work. I think I went a little backwards. I thought it was like gears. You raise them and your rpm raises. So, whats the down side of going to a higher stall? Or is there a down side?
 
Okay, I read up on "How it Works!"

So, how can I choose. Whats the best for an 84' LSC 302?

Drivability concerns in choosing a torque converter - A performance torque converter should not compromise one aspect of car performance to achieve another. When investigating a converter purchase ask whether the particular torque converter being looked at may improve initial takeoff at the sacrifice of top end mph or other similar results, questions, etc. With the technology and product available today a buyer very seldom needs to sacrifice one area of performance to gain in another. However, without proper selection assistance or guidance (and with many under engineered products on the market today) it is unfortunate that many buyers end up with a product that does not best suit his needs or expectations. Too low a stall torque converter will not benefit the customer. If the user has an application which requires at least 3000 rpm stall and they purchase a 2000 to 2500 rpm stall range converter, it will normally not even give them the 2000 rpm stall. It will act very similar to the stock torque converter they just removed…why? Because the engine needs to operate in its optimum rpm range and since the chosen torque converter is below that range, it is not getting enough load from the crankshaft side to operate as designed. Symptoms include engine stalling when in gear at a stop, low stall speed, hesitation when going to full throttle, a "bog" when leaving from stop at wide open throttle. Too high a stall range torque converter will not benefit the customer. You will see this situation most often when the customer does not have sufficient gear ratio for the converter stall range or the engine is not capable of the appropriate rpm range (too small a duration camshaft, inadequate valve springs, too low compression, etc.) Symptoms include high "revs" to pull away from stop, "marshmallow" accelerator feel when driving at part throttle, transmission and possibly engine overheating, and a pronounced engine rev when nailing the throttle from a cruising speed.
 
I guess you got that paragraph from this page..
http://www.tciauto.com/tech_info/torque_converters_explained.htm

From another paragraph there's this sentence:
".. A more detailed discussion of torque multiplication can get very confusing to the layman as high multiplication ratios can be easily considered the best choice when in fact more variables must be included in the decision..."

They do not elaborate on what those "more variables" are.

So it seems like choosing a converter to fit specific needs is not something the "layman" can do as well as a pro could.. I'd try calling that company and asking who can do all the calculations for you.

From what i gather (and this is all new to me) there is no downside to a higher stall speed IF the converter was properly chosen FOR a particular set of driving conditions..

On the other hand, if you are set up for drag racing and try to drive in bumper to bumper traffic, there's gonna be a downside.
 
The only down side is heat build up, so if you plan on changing the converter then I HIGHLY suggest adding a stand alone tranny cooler.

You need to ask yourself what are your plans with the car.
If you are pretty much keeping it a strret car that occasionaly will see strip action, or if its a strip car that will occasionaly see the street.
If its more for the street then try a 3000-3200
If you are building a strip car go closer to a 3500.When you call to order it they will ask you about your car.(the weight, the power, the torque. RPM range ETC ETC) So have those answers ready.
 
joew said:
I guess you got that paragraph from this page..
http://www.tciauto.com/tech_info/torque_converters_explained.htm

From another paragraph there's this sentence:
".. A more detailed discussion of torque multiplication can get very confusing to the layman as high multiplication ratios can be easily considered the best choice when in fact more variables must be included in the decision..."

They do not elaborate on what those "more variables" are.

So it seems like choosing a converter to fit specific needs is not something the "layman" can do as well as a pro could.. I'd try calling that company and asking who can do all the calculations for you.

From what i gather (and this is all new to me) there is no downside to a higher stall speed IF the converter was properly chosen FOR a particular set of driving conditions..

On the other hand, if you are set up for drag racing and try to drive in bumper to bumper traffic, there's gonna be a downside.
Click to expand...

I believe it would cost some money just for them to find out. . .
 
unstoppable said:
The only down side is heat build up, so if you plan on changing the converter then I HIGHLY suggest adding a stand alone tranny cooler.

You need to ask yourself what are your plans with the car.
If you are pretty much keeping it a strret car that occasionaly will see strip action, or if its a strip car that will occasionaly see the street.
If its more for the street then try a 3000-3200
If you are building a strip car go closer to a 3500.When you call to order it they will ask you about your car.(the weight, the power, the torque. RPM range ETC ETC) So have those answers ready.
Click to expand...


1984 MVII LSC
Power: 140hp
Plans: City 50% Hwy 50% w/ a lil Drag Strip
Other Performance: Full xhaust, from the manifolds its 2.25" into the y-
pipe. 2.25 out into a 2.25 cat out the 2.25 cat into Delta Flowmaster 40s,
dual 2.00" out into 2.00 Corvette Xhaust tips. Thats it, thats all she wants
with the 17s Eagles and a tigher suspention.

We also want to know. What would be a good stage one shift kit. She doesn't want it to be jerky. She just wants some good get up an go. When she would like to go. She would also like it to handle better but doesn't want the rough ride. I believe the rear shocks are shot and the bushing in the front are pealing off. Because on hard stops it has a little clunk.
 
unstoppable said:
The only down side is heat build up, so if you plan on changing the converter then I HIGHLY suggest adding a stand alone tranny cooler.

You need to ask yourself what are your plans with the car.
If you are pretty much keeping it a strret car that occasionaly will see strip action, or if its a strip car that will occasionaly see the street.
If its more for the street then try a 3000-3200
If you are building a strip car go closer to a 3500.When you call to order it they will ask you about your car.(the weight, the power, the torque. RPM range ETC ETC) So have those answers ready.
Click to expand...


1984 MVII LSC
Power: 140hp
Plans: City 50% Hwy 50% w/ a lil Drag Strip
Other Performance: Full xhaust, from the manifolds its 2.25" into the y-
pipe. 2.25 out into a 2.25 cat out the 2.25 cat into Delta Flowmaster 40s,
dual 2.00" out into 2.00 Corvette Xhaust tips. Thats it, thats all she
wants with the 17s Eagles and a tigher suspention.

We also want to know. What would be a good stage one shift kit. She doesn't want it to be jerky. She just wants some good get up an go. When she would like to go. She would also like it to handle better but doesn't want the rough ride. I believe the rear shocks are shot and the bushing in the front are pealing off. Because on hard stops it has a little clunk.
 
Screw that ol 84......TBI, no HP, crappy old AOD.

No offense.

As for TC goes....2500 to 3000 is perfect for street/city foot happy action. I would consider not putting to much money into an older LSC (pre 86) IMHO. You are really cutting yourself short just by having the small heads and TBI. If she really wants a TC, then deffinetly go 2500 + and nothing less. And a crappy converter is a crappy converter....you pay for what you get - and there is a difference.
 
BEcontrols is my vote as best shift kit for AOD. Of course I can build Lentech VB in my garage and I still vote Buemann as best shift kit.
 
Check With Hughes

Check with Hughes Transmissions in PHX. They built an AOD for me a couple years ago and it runs great. I got a stall speed of around 2500 to 2800, lower ratio truck gears, and no lockup. With 3.73s I'm running about 2400rpm at 70mph. http://www.hughesperformance.com/
 
Phx tranny in Prescott Valley has killer prices.

$550 tranny
$250 rebuild
$040 Tax
$170 Shift K.

I think those are close prices. I can't remember. . .
 
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