Th400 and hi-hump question

[BCOWANWHEELS]

If I change over from a th350 (low hump) to a th400 in my 1970 lwb do I have to install the high hump in the floor ? i sure would hate to cut my floor board. thanks for the help
bob

[crazy longhorn]

Small block....NO! my 69 came from the factory with a low hump (350/400 turbo). The BB trucks are a different story tho.... crazyL

[BCOWANWHEELS]

so with my 350 sbc a th400 wont fit without installing a hi-hump right ?

[FirstOwner69]

No problem putting a TH400/350 V8 combo in a truck with a small hump. My 69 came that way as Crazy Longhorn said his did.

[BCOWANWHEELS]

thanks fellas I sure didnt want to cut my truck floorboard out.
bob

[Beat68CST]

You can fit a BBC and a 400 on a low hump.


You can fit a Cummins and a 47RH under a low hump too (;

[BCOWANWHEELS]

i also have a cummins 4bt with a A518 I was thinking about for a future truck.

[Beat68CST]

You have to cut the main crossmember and flatten it out to about only 2 1/2 inches tall so you can get the motor to sit flat

[BCOWANWHEELS]

Beat68cst,
you dont have to do this with sbc and th400 swap do you ?

[Beat68CST]

Nooo, SBC and T400 fit perfect. Everything will clear nicely.

You can shoe horn a BBC and T400 under a low hump too.

[DaHos]

Originally Posted by Beat68CST

You have to cut the main crossmember and flatten it out to about only 2 1/2 inches tall so you can get the motor to sit flat

Anyone have clearance photos of the BB and th400 with low hump? Only issue I can see is the longer tail shaft.

[BCOWANWHEELS]

Theres plenty of room for the longer tailshaft in fact you could run the longest tail shaft trans and possiblt run a 1 piece drive shaft. I have a gear vendors o.d. Going behind my th400 in my 1970 truck and a 1 piece shaft with 1350 joints is the route i,am going.