Sinful One RS

Hi all,

Ok, this is the simple, yet dumb question of the day. hehehehe...but I have to ask.

I have a stock 1991 Camaro RS with a 700R in it. I know that it has the ECM controlling the locking torque converter, right? Now, what is the difference between a locking and non-locking torque converter?

I'm building a hipo 350 (455 HP) to drop in and I'm going to rebuild the 700R, however, I notice that when you go to buy a torque converter it says you can buy a locking or non-locking one. What is the difference? What is better to handle the power?

I used to have a TH350 behind a big block and when I bought a converter for that it didn't ask locking or non-locking.

Plus, can I use a non-locking converter on a 700R that is electronically locking??

Someone please help me out.

Thanks much!!! I just don't want to spend my money on something and find out I should have bought/built it differently.

Cya all on the streets...

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

GMTech

You kinda answered your own Q. A locking locks up (which is what you have) and a non-locking does not lock up. The lockup feature is mainly for gas mileage. If I were you, I would get the locking converter, because you can. A locking converter can be made to do the same as a non, but you get the added benefit of increased fuel economy on the highway.

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If you live in Southeastern US, check us out!
South East Thirdgen

"I used to have a handle on life, but then I used it as a plunger and broke it" -The Wave

ASE Master Tech + L1
Savannah, GA
'87 Trans Am-K&N,Cold air induction, SSM SFC, Boxed LCAs, 8mm Accel wires, Flowmaster, 16" GTA rims.
'97 Bonneville SSE

Sinful One RS

GMTech,

So, basically it has nothing really to do with performance? Only that it helps gas mileage in OD? Will it have any adverse effects at the track? So, I take it that the lock up converter just makes sure the trans doesn't slip at all (pretty much like a stick when you take your foot totally off the clutch)? And a non-locking means that the trans still slips a bit...

Ok, I think I'm getting it. I appreciate your help. I'm sure the lockup converter will be 900 million more dollars...but still. Hehehe..

Thanks for the advice and see ya on the streets....

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

GMTech

You got it. Some people actually claim that by installing a manual lockup switch, and hitting it halfway down the track, they actually lost a few tenths. True or not, I don't know.

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If you live in Southeastern US, check us out!
South East Thirdgen

"I used to have a handle on life, but then I used it as a plunger and broke it" -The Wave

ASE Master Tech + L1
Savannah, GA
'87 Trans Am-K&N,Cold air induction, SSM SFC, Boxed LCAs, 8mm Accel wires, Flowmaster, 16" GTA rims.
'97 Bonneville SSE

88IROCs

Another good reason to get a locking converter,...

With the overdrive 4th gear, it is possible to drive for extended periods at rpms below the converter stall point(which isn't really a prob with 3 speeds like the TH350). With the input speed below the stall point, the converter is slipping and generating heat. The lockup eliminates this slippage, allowing low cruising rpm's, without generating tranny damaging heat.

Because you are looking for a new converter, I will assume you will get one with higher than stock stall. The lockup function is even more important in this situation. For instance: my converter stalls at around 2200 rpm, but I go on a lot of extended trips(300 - 800 miles), where my fourth gear rpms are between 1800 - 2000. Without the lockup, the converter would be slipping constantly, and it probably wouldn't take too many of these trips to fry(literally) the tranny.

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He who hesitates,... is lost!

nickd

I agree, stick with a lockup unit.
With the kind of hp #'s you posted, I would recommend looking into a Precision Industries 9.5" Vigilante converter. They are a little pricey but are worth the $. Come with a 2 or 3 yr warranty and a free stall change.
The speed at which the converter locks up is programmed into your Prom. On my 92Z which originally had a 305, the lockup was programmed for 23 mph in the stock Prom which became extremely annoying once I put the 350 in. The stock programming is 34mph for the 350. Depending on how you will drive the car, you may want to go higer than the 34.
I burned a Prom with the lockup at 39mph and was alot happier. Just something to think about.
I also assume your planning to have that 700R built up for the new motor.



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1994 LT1 Corvette Convertible

Sinful One RS

88IROCs,

I understand and agree with you. I do take long trips too like you, so I wouldn't want to fry my converter because I know the RPM's would be below my stall speed. I was hoping to have a stall speed around 2500 RPM or so with the engine I'm building. So, it's a very good tip that I stay with the lockup converter so I don't fry my trans.

Thanks much, I do appreciate it!

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

Sinful One RS

nickd,

Hmmm...I didn't know that the PROM controlled the lockup speed. How much does it cost to "burn" a prom? Do you have to have one originally (like take in a stock one) or do they make it from "scratch" so to speak? Plus, where is a good place to go to to get one burned. I was thinking of the Hypertech Thermomaster chip, however, I don't know how well that would do with a 450 HP engine. I think having the mph higher on the lockup would be better, but I don't want to go too high on it. That would defeat the purpose. I'm definitely building up the TH700 for the motor first. Do you or anyone have any good suggestions on what mods to make to the transmission? (besides the converter of course) If so, I'd really appreciate any information. I don't want to put the motor in it and then find out I forgot one easy mod to the trans and then blow it up. (

However, I do know I'm going to add a transcooler to the car when I put in the better converter. I'll probably run the lines through the radiator and then through the cooler...or would that be a dumb idea? Plus, does anyone know which line is the flow out and which is the return line on the trans? I wouldn't want to run my fluid through the cooler and then into the radiator, that would just heat up the fluid again.

Thanks again for any info!

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain

nickd

Yes, that was true atleast for the 90-92 speed density cars. I had burned my own Prom for my car.
While I have no experience with him, I have heard Ed Wright at Fast Chips does good work. Don't waste time with Hypertech, ADS, etc..for the type of motor your talking about building they would be useless to you. Your going to need a custom. Definetly stay away from Arizona Speed & Marine, I had a bad personal expierience with them and thier "custom" chips.
As far as the trans cooler goes, definetly run the lines through the radiator still. I used a B&M Supercooler, it came with all the parts needed for installation and their stacked plate design is nice. It not only helps with cooling but is more durable to rocks and road debris hitting it. I don't remember off hand but the B&M instructions state which lines are which (in/out).
When your ready, you really don't need anything special in the way of a trans. Just a well built unit to support the hp & tq. numbers your motor will be making. You can go 2 ways, either buy a built unit outright or have find a reputable local shop.
There is a place here in IL. I used called Performance Transmissions who do very good work. He (Chuck) has many levels he can build the 700R to. He does ship out of state. http://performancetrans.com
I have heard Pro Built Transmissons are pretty good as well. It's your call

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1994 LT1 Corvette Convertible

nickd

Check out the Prom board.I'm sure the guys there will have some good suggestions as to where to get a Prom from.

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1994 LT1 Corvette Convertible

Sinful One RS

nickd,

I really appreciate all of your help! Thanks a lot. I'm probably not going to have all this done (due to money restrictions) until March or so next year, but it's good to have all the info ready to go when needed.

Again, I do thank you for all of your help and hopefully I'll be able to post some great track numbers next year!

Cya on the streets....

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Sinful One RS
91 Camaro RS w/305 TBI
3.23 posi w/disc brakes
145 speedo
Z-28 Fog Lights & grille
Sinful One RS's Domain