Turbo 400 VSS conversion for cheap for the RetroC10?

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HotRodPC

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I've never taken a reluctor wheel off a Th400. If its anything like the steel speedo gear, yes it'll be a bitch, hopefully it is the snap ring type. I'd imagine it is, cuz I'm sure its not a good idea to be heating, prying or banging on a reluctor wheel, so you'd thing they'd make them easy on and easy off.
 

davbell22602

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Yes that is one way to tell. Yes they are interchangeable too if you build the trans that way. So when I put my Olds 455 in a square, I'll use the Th400 out of the Olds that has the Variable pitch torque converter, but I'll use the short Chevy Truck output shaft and bolt on output shaft instead of the 9in car output shaft that is not tapped for bolt on yoke.

So why do you guys put car trany parts on a truck trany or truck trany parts on a car trany for? Whats the purpose for it besides just swapping stuff in and out?
 

HotRodPC

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So why do you guys put car trany parts on a truck trany or truck trany parts on a car trany for? Whats the purpose for it besides just swapping stuff in and out?

Many people use what they get for cheap, or what they have laying around. I will have to use the Olds passenger car case to match the bellhosing on the Olds 455 motor, but I will be using the Chevy truck output shaft and tailshaft housing so that I can use the OEM crossmember, and the OEM driveshaft to the truck. I am also using OEM motor mounts out of an 80 GMC that was originally an Olds 350 Diesel. This way its not a hack job. It will be all bolted in with all OEM locations, mounts, crossmembers, dshafts etc. I like things to be different, but still be done with OEM parts and no aftermarket conversion parts of fabbed up parts. When and if I ever get this project done, it'll look like the truck came off the assembly line this way. I'll assure you, this 70 Olds 455 will make a lot more hp and torque than the current 454 that is in the truck now. Then I think I'm going to use the 454 in the 85 K10.
 

davbell22602

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Many people use what they get for cheap, or what they have laying around. I will have to use the Olds passenger car case to match the bellhosing on the Olds 455 motor, but I will be using the Chevy truck output shaft and tailshaft housing so that I can use the OEM crossmember, and the OEM driveshaft to the truck. I am also using OEM motor mounts out of an 80 GMC that was originally an Olds 350 Diesel. This way its not a hack job. It will be all bolted in with all OEM locations, mounts, crossmembers, dshafts etc. I like things to be different, but still be done with OEM parts and no aftermarket conversion parts of fabbed up parts. When and if I ever get this project done, it'll look like the truck came off the assembly line this way. I'll assure you, this 70 Olds 455 will make a lot more hp and torque than the current 454 that is in the truck now. Then I think I'm going to use the 454 in the 85 K10.

ok gotcha
 

GreaseDog

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Yeah, '88 and '89 were cable op. '89 was the only model with a 241 t-case and cable speedo.
the NP208 was ditched after the 1987 model year, and the NP241 was adopted in 1988.
 

GreaseDog

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retro, if you're looking for something to create a VSS signal for your TPI, and retain a factory gauge, look at cruise control equipped trucks, their speedos were cable driven but had a VSS built into the speedo. this type has been used many times to convert to EFI.
 

bucket

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the NP208 was ditched after the 1987 model year, and the NP241 was adopted in 1988.

Nope, 208 was definitely still used in '88:)
 

GreaseDog

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based on owning/working on how many 88s? 208 is a direct bolt in for a broken cable driven 241. the 10 or so 88 Blazers/Jimmys and Suburbans i have been under have all been 241s. maybe early/late 88 is the difference.
 

bucket

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based on owning/working on how many 88s? 208 is a direct bolt in for a broken cable driven 241. the 10 or so 88 Blazers/Jimmys and Suburbans i have been under have all been 241s. maybe early/late 88 is the difference.

Every '88 I've been under has been a 208. Must have been early models I guess.

*edit* Looking on car-part.com for '88 Burb t-cases, they list just a bunch of 208's. Look it up for an '89 model, it's a bunch of 241's from '89 models.
 
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