#1  
Old 03-08-2013, 01:15 PM
tom s tom s is offline
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Join Date: Jan 2000
Location: long beach ca usa
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The reason I said it is to avoid trial and error.As this is the street section and one persons idea of streetable can be diff from the next guy.You have not said what your first gear ratio will be on the ST-10.They make them from 2.43 to 3.42.With too much cam you will loose a lot of bottem end with the 400 and will need to slip the clutch to get it away from a stop.I have done few 400s but a lot of 421s and over the years I have spent stupid money trying to get the sweet spot for performance and drivablilty with many cam changes,rear gear changes and even first gear ratio in the trans changes.With my 62 GP and a 389 crower cam tripower engine I now have a 2.68 in the back with a 3.42 first gear ST-10.My 63 421 Lemans has a 3.90 in the back with a 2.67 first gear TKO600 and my 69 RA III Judge has a 3.55 in the back with a 2.52 first gear Muncie.Good luck with your project.Tom

  #2  
Old 03-08-2013, 03:44 PM
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Felix C Felix C is offline
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Join Date: Feb 2012
Location: Miami, FL
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Quote:
Originally Posted by tom s View Post
The reason I said it is to avoid trial and error.As this is the street section and one persons idea of streetable can be diff from the next guy.You have not said what your first gear ratio will be on the ST-10.They make them from 2.43 to 3.42.With too much cam you will loose a lot of bottem end with the 400 and will need to slip the clutch to get it away from a stop.I have done few 400s but a lot of 421s and over the years I have spent stupid money trying to get the sweet spot for performance and drivablilty with many cam changes,rear gear changes and even first gear ratio in the trans changes.With my 62 GP and a 389 crower cam tripower engine I now have a 2.68 in the back with a 3.42 first gear ST-10.My 63 421 Lemans has a 3.90 in the back with a 2.67 first gear TKO600 and my 69 RA III Judge has a 3.55 in the back with a 2.52 first gear Muncie.Good luck with your project.Tom
No complaints only explaining why I do as I do. I do recall the T-10 had a steep 1st gear. I thought it was 3.44 from reading my first issue of Hot Rod on the return of the Z28. Everyone remembers their first Hot Rod mag. Like losing ones viriginity.

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