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Not that I know of, why stroke one to get 6 more cubic inches?
If you bore the block .030 you get a 406 hence where the name came from.
If this is the depth of your knowledge I`d suggest learning far more before
taking on anything else. There are other things you should know about a 400 before attempting to build one or hot rod it.
 

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As I said, first, learn more. The 400 has shorter rods than any other small block. The 400 is also externally balanced so it uses a specific balancer and flexplate. The main journals are also larger than any other small block as well. The 400 has steam holes in the block and heads and if the heads are replaced and these holes aren`t drilled it`ll do nothing but run hot.
As I mentioned in my other thread, how much money do you have? What kind of car? what rear gears? what transmission? I would suggest moving your questions over to the hot rodding basics forum, that`s where beginners go to learn more. Since 400`s are so scarce, you could likely sell yours for a nice buck and get a 350 and have that much more to invest. Keep in mind engine alone won`t do it, you gotta have gears too.
 

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Google "Tunnel Ram 406"
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5.7" rods will work fine. Get flat top pistons with -6CC 4 eyebrows. You will 9.4:1 compression using 76CC heads. The stock 400 heads are 76CC chamber. or 10.8:1 compression using 64CC heads. For camshaft use Comp Cam 280H or equiv. Becareful when breaking in a cam. You will need special engine oil during the breaking in period. You should get at least 470 to 480HP @ 6200 RPM with 550 ft lbs of torque. The KB400 piston, are they flat tops? Hope this will help you.
 

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I already said a 406 is a 400 bored .030 over. There is no reason why you can`t use the stock crank. You can use 5.7 rods but you will have to grind the block for clearence or use a small base circle camshaft. The clearences will have to be checked during mock up assembly. As I also said, with the little you know you need to learn more before diving in. It`s not so easy you can just throw it together and make it perform. If you use the 5.7 rods you`ll need the correct compression height pistons. Same goes for 6 inch rods. If you use KB hypers the ring ends will have to be gapped so they don`t butt together because if they do the ball game`s over.
If you want to learn the formula to cubic inches here it is:
Bore X Bore X 0.7854 X Stroke X Number of cylinders.
Have the heads been checked? are the guides still good? You mentioned the block is already .030 over, but what is the current bore clearence? If it`s excessive you`ll have nothing but piston knock and the rings will never seal.
That`s why I keep saying learn more before you dive in or the engine will be junk before you fire it up and you`ll spend more money doing it all over again.
 
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