Is something up at Scat?
I apologize to the OP for posting this, but it seems relevant if you're parts shopping.
If you plan on using a 360 block Molnar only offers two crankshaft strokes 3.79" and 4.00" both are only available with the stock 2.125" rod journal size.
Therefore you have to use a 6.123" rod with the stock .984" wrist pins. This is great since most of the off the shelf pistons are made for the .984" pins.
When you use a 340 block the options open up. You can choose 4 different strokes. 3.58", 3.79", 4.00", and 4.125"
The first 3 can be had in either the stock 2.125" rod journal or 2.100" SBC rod journals. The 4.125" is made to use 2.00" SBC journal rods.
I sell all my kits using the 6.123" 4340 H-beam rods for both the 340 and the 360 blocks because of ICON piston availability. This holds the cost down and allows for easier piston
replacement down the road should you damage one. With custom pistons now costing $1600 to $2800 a set using an off the shelf piston makes the most financial sense.
Tom