Flexplate for 406 with THD350
Thread Starter
Racer
Joined: Oct 2006
Posts: 269
Likes: 7
Flexplate for 406 with THD350
I have a completely stock 1977 L48 with a THD350. I am in the process of removing the L48 to make way for a 406.
The rotating assembly for the 406 will be internally balanced and I am not sure if I need a 153 or 168 tooth flexplate. I want to replace the 30 year old flexplate.
If I want to retain a stock style starter which flexplate should I install? I cannot find information that indicates what type of flexplate was stock in a 1977 L48.
Thanks
The rotating assembly for the 406 will be internally balanced and I am not sure if I need a 153 or 168 tooth flexplate. I want to replace the 30 year old flexplate.
If I want to retain a stock style starter which flexplate should I install? I cannot find information that indicates what type of flexplate was stock in a 1977 L48.
Thanks
Racer
Joined: May 2004
Posts: 288
Likes: 0
From: Tigard OR
I have a completely stock 1977 L48 with a THD350. I am in the process of removing the L48 to make way for a 406.
The rotating assembly for the 406 will be internally balanced and I am not sure if I need a 153 or 168 tooth flexplate. I want to replace the 30 year old flexplate.
If I want to retain a stock style starter which flexplate should I install? I cannot find information that indicates what type of flexplate was stock in a 1977 L48.
Thanks
The rotating assembly for the 406 will be internally balanced and I am not sure if I need a 153 or 168 tooth flexplate. I want to replace the 30 year old flexplate.
If I want to retain a stock style starter which flexplate should I install? I cannot find information that indicates what type of flexplate was stock in a 1977 L48.
Thanks
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
It will depend on your engine balance too. Internal balance requires a different flexplate than external. And 153 or 168 will depend on your bellhousing and starter. The 153 used a smaller bell, if I remember, and the nose on the starter to get the gears closer.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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If you're getting it internally balanced then all you need is a regular 350 type flexplate. The idea on a stronger one is always a good idea..but depends on what you will be doing with the car.
To tell if you need a 153 or a 168....look at the stock starter. If the two mounting bolts are staggered..it's a 168 (most likely on a '77)..if they are straight across..it's a 153 tooth one.
Aftermarket mini starters often use bolts straight across regardless of flexplate.
JIM
To tell if you need a 153 or a 168....look at the stock starter. If the two mounting bolts are staggered..it's a 168 (most likely on a '77)..if they are straight across..it's a 153 tooth one.
Aftermarket mini starters often use bolts straight across regardless of flexplate.
JIM
