Possible to go from 350--->427??

simple question. Is it possible to go from a small block chevy 350 to a 427?? I was told that the most you can stroke a 350 is to a 383 by doing so with a 400 crank, and on top of that you could bore it the most of 60 over which wouldnt get you anywhere close to a 427, but if this is true, then why does Summit sell a rotating assembly for a 427 chevy small block? Help me be unconfused. :(

Your best bet is to get one of the taller deck blocks from Dart or WP. I think the bowtie block from GM can go out to that displacement, but not sure. The two blocks I mentioned first will go out to 454 cubic inches or more... i think i saw one motown block that was pushed to 460, but not sure. WP says the motown block will "safely" handle a 4.25" bore and 4.00" stroke (454).

I'm actually contemplating using one of those two blocks for a build up later on, and ditching the LT. More displacement, MUCH larger variety of heads, and a very strong block. Both blocks can take over 2000hp, so a measly 1000hp should pose no immediate breakage or core shift problems.

Im not actually trying to do this, im just needing to know if its "possible" to take a 350 up to a 427

I think the biggest you can go in an LT1 is 396ci. The LS1 I'm not sure of though. I think I have seen some stroker packages for them that are 427ci.

Well the most plausible with an LT1 is 396. Some have gone to 406, 410, 420, and 422. But those were some REAL packaging issues.... lots of machining in the bottom end for stroker clearance and oversize bore sleeves amongst other things had to be done. Too much effort and $$$ for it... especially when you can pick up a new, freshly machined Dart or WP block for less than 2 grand. You could push a little further to a 398 or 399, but for simplicity either stick to a 383 or 396.... or get another block all together. JMO

ok thanks guys. so it CAN be done, im not even specifcally talking about the Lt1 here, people were just telling me that its imposible to take a 350 and turn it into a 427

ok thanks guys. so it CAN be done, im not even specifcally talking about the Lt1 here, people were just telling me that its imposible to take a 350 and turn it into a 427


With a simple SBC 350 yes its possible. Who ever told you that the biggest you could go is 383 is a dumbass. It will require alot of machineing etc but it is possible.

With a simple SBC 350 yes its possible. Who ever told you that the biggest you could go is 383 is a dumbass. It will require alot of machineing etc but it is possible.


Thank You! thats exactly what i was thinking but wanted to make damn sure before going back and telling four or five people they were wrong! :)

The biggest small block I've seen so far is a 454. But it's built on 400 style block with the larger bore. You can't go that big with the LT1 block. On a street driven LT1 I wouldn't go bigger than a 396 because the long stroke makes the rod ratio go in the crapper greatly increasing side loading on the cylinder walls.