If your using hypers maybe, But we have been using the SRP pistons with the 6 inch rod with no problems and all the blocks we prepare we torque plate hone them which makes quite a differance as compared to shop that doesn't.
If interested I have a NEW 383 engine kit with a internal balance Scat 4340 Crank all balanced , Micro polished, SRP flat top pistons for a 6 inch rod that are pin fit and a set of Scat 6 inch rods with the 7/16 bolts and both ends have been clearanced comes file fit rings all fitted and it also comes with a BRAND NEW GM BLOCK that has been line honed with an ARP main bolt kit, Decked to 9.000, Stroker clearanced, Bored and torque plated honed with peformance cam bearings installed and brass freeze plugs. Machine work has been done on a HAAS 4-axis CNC machining center and the block was plated honed in a Sunnen 616. And FREE SHIPPING IN THE U.S. for 3295.00
The Customer is going to a big block and just wants to get rid of it, If you want some pics pm me and iwil get some to you.