Here's the deal, I have my 350 already bored and ready to go on the engine stand. I need heads, cam, and engine kit and she'd be back on the road. However, I have a virgin bore 400sb sitting in the floor untouched. My HSR would bolt right up to it. But, the catch is, it has no crank, rods, etc. Now, would it be worth it to go ahead and spend the money to buy all the hardware for the 400 and bore it, then drop it in my '89 Iroc? Or should I just go ahead and finish the 355? Any comments will be appreciated. Thanks in advance.

 

I assume that you do have a crank & rods for the 350 shortblock...

If so, buy the bearing spacers that allow you to put a 350 crank in your 400 block, fit 400 flat-top pistons on the 350 rods and you have a 377ci. They work very well.

 

Of course I have all the components for the 350, it is the motor that came out of the car originally. I would do the 377, but it just seems like a waste of a good 400 block to me...just not a big fan of them.

 

It seems like it would be a good idea to price out a few kits and then ask yourself if it's worth it. There are cheap kits and expensive ones.
To some guys it's worth it to spend $800 on a set of shaft mounted rocker arms.
If it were me I'd finish off the 350, then start on the 400.
Or maybe I'd build a 377.

 

I'd do the 400 now and save the 350 for a future project. Other than the 350 is machined the cubic inches in the 406 are cheap when doing a rebuild.

 

There's no replacement for displacement.....if you can afford it!!!