I was wondering if it was possible to use a 4 inch steel crank, have it turned down to 327 rod journal sizes by offset grinding it, and still being totally safe and streetable. Mainly I was wondering if the block could take it. I was wanting to make around 400 horsepower and only turn like 5000 rpms, and do it fast because of the lighter weight. Someone let me know if its possible.....any helps appreciated.

I don't believe a 4.00" crank will fit in a production smallblock. You will need an aftermarket block with raised cam location.

why? it appears you have a older 2 bolt 327 block and a 4" crank. neither will work together. you need an aftermarket block or a crank to fit your block.

I was going to get a 4 inch stroke crank for a 400, have them turn the mains down to the 350 size, then offset grind the rod journals down to the 327 size. I was wondering mainly if the rotating assembly would even fit, and be structurally sound. Would it be possible to get a reduced based circle cam, and notch the block? Thats what I was wondering. And well of course if the block can take it.

A 4" 400 crank? They came with 3.75" stroke. You could offset grind that thing +.35" (2.65-2.30) to come up with 4.10" stroke. But you will break the crank, hit the cam and hit the block. You can not do it. As i said before you can only do it in a aftermarket raised cam location block, which can except upto a 4.0" stroke maximum with grinding.

You can't do it!!!!!!!

I can't imagine getting any kind of nut-and-bolt rod into a stock block with that much stroke, with any amount of grinding that wouldn't destroy the integrity of whatever part you decided to grind on.

And, it would be utterly foolhardy to expect those already known to be fragile rods, to hold up to that amount of stress.

All in all, it would only produce a 408" motor, take a tremendous amount of money, be rather unreliable (one missed gear...... it's toast), and lose races dependably to a stock 400.

if you are wanting to take a 4 inch crank you would be best off taking it to a 400 creating a SBC 427

but even that would take lots o' money

Alright.....thanks fore everyones input. I didnt know that it was impossible with a stock block.