Ok i have a 1989 150 5 speed... i am getting a 1970 340 to put in it... has anyone done this swap before?

 

is this 340 internally or externally balanced? and your current motor is it externally or internally? depending on this will decide what type of flywheel and pulley system will work, older 340's have cast iron water pumps, which means you might need a new rad hose or depending how it works out maybe even a new rad

 

i believe they are both externally ballanced and im not sure about the water pump but why would i have to change out the rad?

 

I know all the older 318's and 340's are internally balanced. The only externally balanced small block is the 360. So you shouldn't have any trouble. Check the back of the 340 crank to be sure it's drilled for the pilot bushing. I've swapped cranks from "blown-up" 340's to 318's, rods will work also. The only problem you may have is where all the accesories bolt.

 

Ok i should have prob put this in earier but my truck has a V6 in it right now will that make any difference?

 

Not sure about the six.

 

Oh ew... the V6. You'll need new motor mounts, tranny, wiring, exhaust, maybe radiator... I was going to swap my V6 for a V8 but ended up swapping the chassis as it was easier lol