Gary Berg

Hi im doing a pontiac 455 engine and th400 tranny swap into a thirdgen and i was wondering what is the difference between long tail and short tail th400's? pictures would be nice.
Thanks, Gary

AlkyIROC

I'm not sure there is such a thing with a TH400. All the ones I've ever seen have a short tailshaft.

50bmgshooter

iTrader: (4)

there is a long and short tail 400
nobody builds long tails for racing
the tail shaft is to long and cant hold up to the power

Atilla the Fun

Didn't you get one with the engine? You can't run your third-gen's original driveshaft, so you can use either short or long. Long has the benefit of a shorter driveshaft, reducing unsprung weight. But short, if you already have it, has the benefit of you already having it, if you do. (redundant, huh?) And if you're making enough power to need a TH400, then you're making enough to need a driveshaft with a stronger tube than just having your stock one shortened and fitted with a TH400 slip yoke. If I'm not mistaken, the Hurst kit will work with either, if you wanna run your stock torque arm. The BMR Fabrication torque arm is a good bit shorter, so again, you could go either way. As for the mounting, no difference. Doing a driveshaft loop may prove easier with a short-tail. If you want to add a GearVendors OD, you'll need the short tail. Sorry, no pics.

Gary Berg

i think its a short tail. i searched it and mine looks like the short tail. i know i cant run the original driveshaft im going to buy a driveshaft from spohn.

50bmgshooter

iTrader: (4)

tail housing on a short tail is about 6" and on a long tail its about 12" IIRC

Gary Berg

ok ya its def. short tail ill try to get pics to confirm.

Gary Berg

Atilla the Fun

that's the short.

50bmgshooter

iTrader: (4)

Gary Berg

Are they better than the long tail? im eventually going to make it a street/strip car.

50bmgshooter

iTrader: (4)

yes the tail shaft is longer and not supported right for higher hp
thats why all tranny shops build short tails