Impossible- - - - -a 261 has a 3 3/4" bore, and you'll hit the water jacket before you get a 235 bored that big. The 261 has a totally different cylinder wall thickness and the adjoining cylinders are "siamesed" together to allow the necessary machining to fit a piston that big. There are also extra cooling holes in the cylinder head to accommodate the lack of water flow between the cylinders.
A 235 and a 261 use the same crankshaft, so the term "stroker" definitely doesn't apply. The 261 crankshaft can be offset-ground to use a 292 connecting rod for a stroke increase, but a set of custom-made pistons are required to make that combination work. It's possible to get almost 300 cubic inches from a 261 block and a stroker crankshaft with the right piston/rod combination, but get ready to spend mega-bucks to build that engine!
Jerry
Last edited by Hotrod Lincoln; 02/07/2014 5:54 AM.
