Great thread Andy..
While I agree that the EZ's are more than capable of reaching the #, and definitely more economical...The "Default Combo" would probably include Indy 440-1's simply due to the huge numbers of these heads already in racers hands! I'd venture to guess that a larger group of racers looking to move into the 700HP range, will be putting strokers under thier existing heads, rather than putting larger heads on existing shortblocks.

In my case, I absolutely love my 440 with Edelbrock Performers, M-1, and 304/640 ultradyne solid. With a best of 9.96-133 on the motor in a 2880 lb Challenger, and around 129-130 in SST, it has served me well for 5 seasons.
So I want to step up without robbing anything from that engine, allowing it to serve as a back-up or for another project.

Here's what I have so far to that end:
'70 RB Block, 4.350 bore, tall fill, BRC aluminum Caps & ARP Studs.
OOTB 440-1 heads: they will be prepped, and cleaned up by my machinist.
1150 Dominator, Milodon Dragster pan w/ single line system, 2 1/8 headers

My plan was to use the 4.25/7.1(2.2 journal)/Ross flattop kit from 440 Source.
I don't have an Intake yet, I was considering a 440-2 since I already have an adapter which has 2 stages of N20 plumbed in, hood clearance may be an issue however, so the 440-3 with a fogger may be the answer?? The 3X is out of the question...it'll never fit.
After watching my brother struggle to keep Indy rockers alive on his 504..(he finally made a whole season this year..by dumping his roller cam, and going with, you guessed it A .620 MP Solid!!) I'm definitely getting T&D's..So do I get 1.6, 1.65, 1.7??
Next question is Cam...I have a 280/282 @.50 .660 lift roller (w 1.5) 108 LSA available on the shelf...I'd really love to get it done with a solid though.

The goal is this: I'd like to go 8.99-148 once on motor, In my 2880 lb Challenger with a 1.76 Glide, and 9 inch converter, 4.30 gear. Consistant 9.10-9.30's would be fine, 142 mph in 10.90, 144 mph in 9.90 trim.
Is that doable with a default 700 hp combo?? do I need more? Can I hit it with any N20 at all without grenading it??