4-SPD to Automatic
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4-SPD to Automatic
On my 88 F150 4.9L 4-SPD Man.,If I wanted to convert to auto,would the torque convertor for a V-8 small block be proper as for as counterweight is concerned. I know I'll have to get a flexplate for the 4.9L. How about crossmember mods.,if any.How about mods. to the mechanical speedo. ratios to match my original trans. I would like to install an AOD or AODE with reprogrammed valve body to upshift properly {I've read in HOT ROD this trans upshifts from 1st to 3rd unless the stick is in the 2nd position,but can be modified}.
Phillip
Phillip
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From: Durham
4-SPD to Automatic
Phillip,
Yeah, the flexplate does not have any counter balance. From my understanding, it does not make a difference on the torque convertors as far as the engine size. The only difference in the convertors is the stall speed. The higher the rpm stall speed, the more engine rpms it takes to start the convertor spinning and consequently transferring the power to the wheels.
'82 F150 w/351W (orig 300 I6)
Steve
Yeah, the flexplate does not have any counter balance. From my understanding, it does not make a difference on the torque convertors as far as the engine size. The only difference in the convertors is the stall speed. The higher the rpm stall speed, the more engine rpms it takes to start the convertor spinning and consequently transferring the power to the wheels.
'82 F150 w/351W (orig 300 I6)
Steve
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4-SPD to Automatic
When you swap your tranny to auto you should get a matching torque converter because motor size determins the stall speed. Incorrect stall speed could have adverse affects on your power and performance. I belive the crossmember and rear tranny mount will interchange with no mods. For the speedo to work properly you should retain the gear that came in the truck as it matches your gear ratio, and the same gear will work in an auto or manual. The drive gear on the tail shaft may need to be changed to match your application.If you are unsure have a trustworthy tranny mech. look to see if they match. You want the drive gear to be the same "color " as the one in the tranny you took out.
hope this info is helpfull
gary
hope this info is helpfull
gary
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