Any reason to pick a TH350 over a TH400?

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Kapdin

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Im just lookin towards the future and when the time comes I think i want to transplant my 400ci/th400 out of my k30 and into my k20 and then a new crate 454/4l80e for that. But just wondering if there would be any reason to stick with the th350 i have in there now instead of puttin the th400. Im not going to pull all that much with it but want it to take a heavy foot.:happy160:
 

Swims350

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gotta have different t-case adapter and trans mount or crossmember?

Also driveshaft or shafts, then it's gonna take more power to use the 400 compared to the 350.

also the kickdown switch for the th400, since it's electric and firewall mounted by th epedal.
 

Kapdin

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humm, i see, i see. Well my goal is to ditch both np203's any ways which will make me change the crossmember and gives a chanse to change the pattern but not liking the sucking more power part.
 

Swims350

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not sure how much power difference is but there is some from what I've seen.

The 400 is supposed to be the stronger one though of course.
 

Kapdin

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yea ive heard that and understand its the beefier one. But the more i think about it.....i really don't need the 400 in there. According to HR you can build a th350 to hold alot of hp and like i said im just putting that 77 400 in there and maybe bolt some hp to it but what headers,intake,cam maybe push 215hp? but i guess it does have mess of tq. This truck is just going to be me fun truck and beat it up a bit but not really pull anything.
 

bucket

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I would just keep it simple and leave the th350 in there. It should hold up to it fine, and if it doesn't then a good rebuild will take care of that... and for probably not much more $ than buying a t-case and adapters as well as having the shafts done.

My old '77 K5 came stock with the 400/th350 combo.
 

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