I haven't had a 235 apart recently enough to remember what the rod bolts look like. The old 283's and early 327's had 11/32" rod bolts, and the 350's moved up to 3/8" diameter. ARP uses a super-strong alloy that needs 50 ft.-lbs. of torque, or the torque-to-stretch method of tightening. I'll bet an existing rod bolt could be fitted to the 235 rod, without having to have them custom-made, even if the hole in the rod has to be reamed to fit. The rod will need to be reconditioned after installing the new bolts anyway, something we always do when retrofitting to ARP race bolts. By setting up a jig in a valve seat and guide machine, and using valve guide reamers, I can make the rod bolt hole just about any size you want, accurately.
BTW, to get the correct amount of bolt stretch on a 7/16" diameter bolt in a Carillo rod for a 350 engine, it's necessary to use over 90 ft/lbs of torque. Those rods cost $1,000.00 per set, back when we were using them regularly.
Jerry
