What's the weak link in my 440 build?

I do have a nitrous system installed but have yet to use it. I think it was good up to a 300 shot which is more than I’d ever need. I’ve got forged pistons and the rings were gapped for nitrous when I installed them. Though I could only find chrome moly rings in .040 size. I think if I get it tuned appropriately and then use nitrous to get me to 650hp I would be happy. I think I want to avoid doing a stroker as that would be a complete rebuild on a basically new motor.

I’m thinking the rods will be fine as long as I keep the rpm’s low. It seems to me that rod failure is more related to RPM and piston weight than horsepower of the motor. I would guess the most stress is put on the rod during the intake stroke as the crank is pulling the piston downward. I read somewhere about a 1000hp supercharged 440 using six pack rods and not having any issues. It made peak power at 5000 RPM. Where as there are plenty of instance like Hot Metal mentioned where the rod failed at much less horsepower but at a higher RPM. Am I crazy or does this make sense?

The cam I have now never gave me any problems with bucking or needing to feather the clutch with the 25.8” tires and 3.55 gear. Once I get the taller tires and deeper 4.10 gear my overall ratio should be very close to the same so I think the setup will remain street able. Although if I go through with the head change and bump up the compression, I guess that could change. If I end up having problems I'll look into an in dash timing controller. It might be nice to have with as hot as it gets in Arizona where I'm headed. I’m sure I could have faster, more consistent times with an automatic but I love that 4 speed so much it’s just not worth it to me to switch over. Same reason I still have the front bench seat. It weighs a ton but I couldn’t picture putting anything else in there.

I do have plans to pull some weight off the car. I’m going to gut the doors as much as possible keeping them stock looking and functional. I also will be putting on fiberglass fenders and hood as well as some lighter brakes. I’ll probably gain about 40lbs back when I put the roll bar in it. I know I can’t have my cake and eat it so to speak but I don’t want to drive a completely gutted car around. I’ll remove as much useless weight as possible without sacrificing functionality and whatever it weighs is what it weighs.