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Old 03-19-2012, 04:25 AM   #1
Rifter_Chevy
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Turbo 400 shift points

I swapped out the engine on my truck over the past few weeks and have it back together and running. However the shift points are a good 1000-1500 rpm higher than they were with the old engine. What would cause this?

The vacume line and electric kickdown wire are both connected.
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Old 03-19-2012, 05:16 AM   #2
cory d
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Re: Turbo 400 shift points

It might not have enough vacuum so its causing it to hold on longer and with no vacume at all it will shift when the governer tells it too. which will be way too late
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Old 03-19-2012, 06:37 AM   #3
Rifter_Chevy
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Re: Turbo 400 shift points

Well im using the same carb/intake/vacuum port as the old engine so it should be getting the same amount of vacuum. I will check the line for breaks and make sure the line itself is not the issue.
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Old 03-19-2012, 12:26 PM   #4
Corts60
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Re: Turbo 400 shift points

I agree with Cory that you need to check out your vacuum. Does your new motor have a big cam?
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Old 03-19-2012, 10:59 PM   #5
Rifter_Chevy
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Re: Turbo 400 shift points

Quote:
Originally Posted by Corts60 View Post
I agree with Cory that you need to check out your vacuum. Does your new motor have a big cam?
It sounds like it might have a mild cam. The engine dropped in was of unknown origin, it sat in a barn for years but was stored with oil in cylinders and turned over freely by hand. We replaced alot of stuff and dropped it in, took my old carb/intake and dropped it onto it, and replaced all seals and gaskets and frost plugs. Engine runs great, just trying to chase down this shifting issue.
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