Hey all, havent been on here in a while, but, got a question.

Ive built up a nast 355 Vortec motor, and have got a shop to build up a Probuilt 700R4 with the proper thirdgen tailshaft. No my car currently has the 2.8L with the auto (the car is an 85)
**and before you ask, i did a search, nothing came up**

I was wondering, is my driveshaft from the 6 going to need to be lengthened, shortened or be left the same?

Thanks all!

G

 

If the transmissions are the same type, then your driveshaft will stay the same lenght.

The engine has nothing to do with driveshaft lenght when useing stock engine crossmember bolt holes.

GM built all there cars so the rear of every engine used in that body style ends up in the same place, by moving the motor mounts to diff spots.

If you look you'll notice the theres a few sets of bolt holes for motor mounts. The v-8's uses the front set, where the 4 and 6 cyl used the sets closer to the firewall.

So if you dont change the lenght of the trans (install diff trans) everything from rear of engine back will be in the same place as before.

In 85 if you have an auto trans it will be a 700r4, and your installing a new 700r4 so you'll be fine