hi guys, I would like some advance for my skylark. it has a 350 engine in it, but i want to change it over to a 430 engine. i know i will have to change motor mounts but what about the trans and the drive shaft? is the yoke the same size? will i have to cut the drive shaft? any help would be grateful...........Mikeo No:
A 400-430-455 should mate to the TH350 no trouble, they're all the same family, so to speak. That's the route I went. The problem is a TH350 isn't really going to handle the torque well. My original TH350 lasted from when the car was new to 1997. I had swapped the 455 into the car and bolted it to the TH350 six years earlier, and it saw daily driving duty, 52 weeks a year, about 12-15000 miles a year. In 1997 I lost reverse in the TH350 (which leads me to assume that it's demise wasn't from the engine) and I replaced it with a pro-rebuild at my local Hydramatic place. They supposedly beefed up the tranny, at my request, but who really knows? I'd suggest a tranny cooler for the 430. I need one too, but I keep putting it off. But no troubles with the TH350 I have since '97. I only drive the car in the spring and summer now, but that tranny has to have 20 thousand miles on it with no signs of ill effect. I know a lot of guys like to yank the engine and tranny as a unit, but I've never done it, I never have the space available. I just support the tranny with a small floor jack that has some wood on it to spread out the load, and take the tranny bolts out. There's a guide pin and pilot that helps re-alignment. Sometimes juggling the engine onto the mounts and into the tranny can be interesting...I usually loosely bolt the mounts to the pads, then shift the engine over the mounts and install the mount bolts into the block. It never seems possible, but then I just crawl under the stupid car and make it work. It's very do-able, but sometimes I need to sit and think out how to get the block to sit where I need it...a little higher on the jack? A buddy pushes the block a little this way? Maybe there are special considerations for a 430 that I don't know about, but as far as I know, the two engines are similar enough to have minimal difference in installation. Have you considered building up the 350? There's lots of power to be made with that engine, too, and you wouldn't have all these hassles. A 430 is pretty damn cool, but 'little brother' is a good engine, too:TU:
