ive been having issues with the 400 in my truck, and im starting to thnk it might be something serious that will require a re build. i figured this would be a good excuse to do a swap. i found a guy selling a running 429 with a factory 4 barrel intake out of a school bus, not sure what year, for $400. anyone have some good or bad input?
Medium duty 429s differ from car/pickup 429/460 motors. Crank snout might be bigger, accessory drives different, bell and pilot hole in crank different. Not 100% sure on this, but when this comes up in the large truck forums where folks want to swap a 460 in where their 429 was, it turns out to be more trouble than it's worth.
Having said that, you aren't swapping from a 460, but this will be about the same as swapping a 400 to a 460, including a 100 lb + weight penalty. Figure a bigger radiator as well, along with exhaust, and all the other little things.
You will have to deal with the trans issue also--what trans do you have?
$400 won't go far on a rebuild of your 400, but it you end up spending another $400 on little and not so little items, maybe......
PLUS what condition is that 429 in? Have you heard it run?
You would end up with a bit more power than the 400, but not by much.
true. i need this truck as its my DD during the winter months, so if it needs a re build ill ust go to the junkyard and buy a different motor to build on the side. but if im gonna do that, i may as well go with a big block.