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  #151  
Old 10-19-2022, 08:24 PM
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post a pic of the converter both sides.
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  #152  
Old 10-20-2022, 12:31 PM
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Thanks Donnie. Converter is in the car now - so when I get the car back home from the mechanic's house, who is doing the work for me, I'll see what pictures I can come up with

I believe from what I remember the trans is from a 1970 or 71 Impala (from the trans code on the side of the case). Also the shifter lever is for a column shifter - we are swapping that out this week for one for a floor shifter.
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  #153  
Old 10-20-2022, 01:44 PM
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If the converter is still from the Impala, it's not going to work with the L78 cam, as you are aware of. You'll need a converter to match the application, with a higher "stall" speed, either a rebuilt original or an aftermarket tuned to the cam.
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  #154  
Old 10-20-2022, 02:55 PM
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Thanks Mitch. Yes you're right. I need a converter that will let the engine idle higher in gear - but I don't want a real high stall converter either. I enjoy the Pure Stock Muscle Car Drags and would need a converter that wouldn't blow-off F-70-14 tires.

But if I understand correctly - the stock converter did let the engine idle at about 750 rpm's and had a 2,200? rpm stall
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  #155  
Old 10-20-2022, 03:20 PM
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Quote:
Originally Posted by TomN View Post

But if I understand correctly - the stock converter did let the engine idle at about 750 rpm's and had a 2,200? rpm stall
Yes,as that's what my L-78 TH-400 transmission lets it idle at.
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  #156  
Old 10-20-2022, 11:43 PM
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Post L78 with TH400...

Quote:
Originally Posted by Too Many Projects View Post
If the converter is still from the Impala, it's not going to work with the L78 cam, as you are aware of. You'll need a converter to match the application, with a higher "stall" speed, either a rebuilt original or an aftermarket tuned to the cam.
The idle aspect is only part of the transmission issue...the hi-perf trannys used behind the L78 were special built units. They had stronger internals, the 6 lug high stall converter, a hi shift point governor and other unique features. There was an old thread about this, not sure if the info is still accessible.

https://www.yenko.net/forum/showthre...ighlight=trans
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  #157  
Old 10-21-2022, 02:49 PM
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Thanks for the info on the transmission. Right now the trans seems fine, I'll know more soon as the car is getting close to being drivable
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  #158  
Old 10-21-2022, 09:49 PM
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And the new Disc Brake Hold Off Valve leaks ..... so I've ordered another one

The transmission in my car has a "CR" code with a black tag - no picture, but the torque converter only has 3 bolts.
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  #159  
Old 10-22-2022, 02:10 AM
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Post Th-400..

Quote:
Originally Posted by TomN View Post
And the new Disc Brake Hold Off Valve leaks ..... so I've ordered another one

The transmission in my car has a "CR" code with a black tag - no picture, but the torque converter only has 3 bolts.
For 70-71 the 'R code' TH-400 would be a 454 application from a Chevelle...

The 3 lug converter indicates a low-horse option...
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  #160  
Old 10-22-2022, 05:04 PM
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That's what I was thinking - but no way to know IF the trans has been up-graded without taking it apart, and I don't plan to just do that with the trans working good.

But the converter has to be changed
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