LOCKUP Torque Converter C-6

Brianedwardss

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I've calculated the 'slippage' in mine out to 5.5% at 65 mph using gps and an rpm formula. (high speeds/flat country i figured should be where it'd be the closest to 'lock'). I was expecting more like 1-2%.
 

david85

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I heard slip generally between 2% and 10%. There were times when it felt like I was easily reaching that 10% thresh hold when I still had my C6. Slip can be even higher if you are below stall speed. But 10% RPM slip doesn't mean 10% loss. A lot of that slip is converted into extra torque. The conversion is not 100% efficient however, and that wasted energy is dissipated in the form of heat. The torque converter is a brilliant device, but it can never match the mechanical transfer efficiency of steel gears.

When my E4OD unlocks, the truck actually looses speed for the same light throttle setting on the highway. For moderate hill climbing, I have to really lean into the throttle to get that extra pull if the converter unlocks. Although I'm not sure if the E4OD converter is as efficient as the C6 since its designed to stay locked most of its life and not rely on the fluid coupling. It could be an apples to orange comparison.

I don't think I can really add much to the topic of this C6 automatic locking converter upgrade because I can see some serious problems (some of which have already been brought up) and until its tested in a vehicle, it's only an idea.
 

crashnzuk

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That thing looks kinda deep, I assume it will fit inside a stock bell? It also seems like it'd be better suited to a car or commuter type vehicle than a tow-rig. I would think there would be too much slippage before total lock for it to last very long if you were putting some power through it with a load strapped on the bumper. I may be wrong though, I'm not an engineer. It seems like a great idea and I'd love to see how it works.
Travis..
 

LCAM-01XA

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When my E4OD unlocks, the truck actually looses speed for the same light throttle setting on the highway. For moderate hill climbing, I have to really lean into the throttle to get that extra pull if the converter unlocks. Although I'm not sure if the E4OD converter is as efficient as the C6 since its designed to stay locked most of its life and not rely on the fluid coupling. It could be an apples to orange comparison.
Oh, the E4OD converter is a very loose thing, at least mine is - if I'm on level ground maintaining a steady speed I usually get 200 rpms difference between locked and unlocked, which is pretty negligible, but the moment the driveline starts loading up (such as pulling up a hill) the rpm difference starts increasing, I've seen as high as 600 rpms difference in 3rd gear. No C6 that I ever had the opportunity to drive was so loose...
 

david85

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Oh, the E4OD converter is a very loose thing, at least mine is - if I'm on level ground maintaining a steady speed I usually get 200 rpms difference between locked and unlocked, which is pretty negligible, but the moment the driveline starts loading up (such as pulling up a hill) the rpm difference starts increasing, I've seen as high as 600 rpms difference in 3rd gear. No C6 that I ever had the opportunity to drive was so loose...

The converters feel pretty close between the C6 I had and my current "low stall" E4OD converter when driving normally. The C6 converter might have been factory original since it had a "1986" stamp on it (transmission was more than likely rebuilt). I only see 600 RPM of difference when I am below stall speed thresh hold and in cases like that hard throttle will cause a downshift one gear to put power transmission back in control of the gears. Once I'm slipping that much, its time to dowshift anyway. In the 2300 RPM range, slip is usually limited to about 300 RPM.

I've never driven a truck with a custom low stall C6 torque converter so I don't know how tight those can be made but mine would easily slip 300 RPM well over 2000 RPM when pulling hard.

What I notice with mine, is when climbing a steep incline in 1st gear, it would have to reach about 1400 RPM with the C6 before it would start to really "catch. The E4OD is about 1000 but gearing difference is likely also playing a role.
 

LCAM-01XA

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Yeah, my converter ain't stock either, but hell if I know what it actually is - it's bright red in color, has a massive front half, and lacks a drain plug. Real descriptive, I know, but there ain't no single marking on that darn thing, unless there's a label on the front face where it's hidden by the flexplate. In any case, my cruise slip is 200 rpms, the moment I tip in the throttle I'm already at 300-400 rpms lip, and under heavier throttle (but not heavy enough to downshift) she's up in the 500-600 rpms slip. Tell you what tho, that thing sure works great when I need a gear between the stock 2nd and 3rd or between the stock 3rd and 4th... And yes mine don't "catch" till 1200-1400 rpms either, under the same conditions of pulling uphill in 1st gear. Guess I got some odd beast then, lol
 

idiabuse

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I run a low stall Ford Motorsports converter now, I also use a low drag C-6 torrington bearing transmission.
I also installed a reverse manual racing valve body to eliminate the auto shift that I hate about the C-6
With that said I always drive around in 3rd gear, even from a dead stop and the converter flashes up to 1100/1300 rpm depending on the amount of throttle I put in.
Take offs are smooth and I could drive it around all day and not see anything over 1500 rpm if I did not need to go faster than 45 mph.
I cant wait to try this new converter out, I can modify the stall to help with the turbo lag but still get lockup in every gear.
I have a GV overdrive bolted on the back too so lockup is a big advantge without having to go to a E4OD


Javier
 

idiabuse

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has it been tested at all yet? any results or is it still just talk? sound great to me

Our launch date for the C-6 and THM 350-400 Eco-Matic converters is June the 1st 2011. We are in the process of getting lids made and doing some more testing before we go to market with them. Everything is looking great with the test me have run so far!

reply to my e-mail a few days ago


Javier
 

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