Great info in this thread so far. You already have feedback from some of the smartest guys on the forum and if I know anything about this stuff, I learned it from them so I don't know what else I can add except a couple of opinions.
@BergmanAutoCraft mentioned 1.12" torsion bars....and I would listen to this advice. While lots of guys refer to the 1.08" bars (and those are a big improvement over stock), the kind of driving and modern tire performance that you're looking for will be able to take advantage of a stiffer spring.
@72bluNblu is always a font of incredibly valuable and precise information here but one concern that he had was about the final drive and I'm not sure if I agree that it's a problem. Unless you're addressing the aerodynamics of your car, your top speed will be limited by how pee-resistant your seats may be. I've only approached 120 mph in my Dart a few times and even with upgraded suspension components, it starts to get dicey. Much faster and it would stop being fun...just my opinion but I will bet your 3.55s will do fine on the top end. You'll have the power to use almost that whole speed range on a long straight but you may not want to anyway.
A couple more thoughts--
Unless I missed it in my early morning, pre-coffee haze, you didn't mention seats...if you're thinking of running stock bench or stock buckets...think again. You're going to want a lot more lateral support.
Unless I missed this too, you might benefit from a battery relocation kit to shift that lump of weight to a more useful spot...
Keep an eye on your oil pressure. You probably have a windage tray in your pan of your built motor. In case you don't, high cornering Gs while pulling 7k could run you out of oil You may want to consider oiling system upgrades before you spin a bearing. :)
It sounds like you're building my dream car. I'm going a similar direction, but I'm way behind in terms of engine/transmission equipment...your combo sounds like a blast...while my stock Magnum 5.9 and built A904 need to be sent to a new home...at this point I've settled on saving my scarce time and buying a crate motor from Blueprint (or another reputable builder)...and unfortunately, I also need to save up for a manual transmission swap kit which is killing me. I keep the quote from Silversport pinned to the wall so I remember to stay on task. :D
Good luck with your build and please keep us posted!
