Some folks dont like their slugs, but I also used SRPs hung on my old L88 rods, and it made surprising power with the cam/head combo Mr Brookshire dialed in for me. 10.5:1 alums. The slugs looked great upon re-fresh. coming up on 28K miles, but now its doing an 1/8 mi at a time!
The 7115 was originally an L88 crank I was told. That is what my crate L88 had. So, from the factory , it was likely balanced with the 11:1 TRW medium dome slugs. Pretty heavy. Maybe it was also used in 375hp 396 apps tho, IDK? Always thought it was 427 only.
Hey 66, you're only shooting for 500, so the whole rod length thing is pretty academic. Now, its your call, but 427 make GREAT POWER to 700 rpm, like a small block. But as the pro has indicated, using a hyd roller may limit that somewhat. CERTAINLY dont do the stock Comp cams /350 lb spring thing. It wont rev and give teh short stroke rat it natural advantage.
Who ever said hockey puck and long rod rev to the moon never owned solid cammed , well sprung 427... they rev to the moon just like the General built them. 8000 rpm mine saw, no issue. ( clutch overcentered on powershift- no pill in
So I may suggest forget the rod length debate and focus on valvetrain stability that lets that 427 eat. For the record, Straub told me he'd set me up with a HR stable to 6800 rpms, so my 427 could enjoy stretching its legs. Or, I'd just run lighter solid rollers on the hyd cam.
( you could make near 600 with the right heads/cam btw as he will tell you! )