[ERA Chas]

Subtle things make a difference in weight and mass location. All aluminum engines vs. all iron or iron/ally combinations. My aluminum rad is 1/2 the weight of my old copper brass. Battery location-trunk or footbox?
Every single one of our cars is unique in the equipment content and the location of key items. 350 wheel HP is more than adequate for a serious race car so it's not necessarily the 600 HP gang that wins hands down.
So a blanket statement like SB's are better roadracers than BB's is BS. It's the setup of each individual car that makes one or the other produce better lap times. And that's omitting the driver skill factor.
Here's what it would take to find merit in a SB vs. BB racing evaluation-in my opinion.
Two identical rollers must be sourced from a manufacturer.
For the sake of discussion, ERA or KMP. Both chassis are available to carry SB's and BB's. Each chassis should get one type of engine-an FE and a 9.5 deck Windsor. (An 8.2 deck would make the weight difference greater but have trouble matching the FE's torque). They should have iron blocks, aluminum heads and waterpumps and carry a single 4 bbl. They should each produce the same power output-let's say 500 FWHP. The engine's location should be determined by the location of the trans mount on the chassis. That keeps their mass consistent in each car. Chassis should have same gearbox, driveshaft and rear gear. They should be weighed with corner scales and carry the same brakes and tires. The only difference so far is that the Windsor will weigh maybe 40 pounds less than our sample FE.
Then they should do timed laps over a technical course like Watkins Glen (I think Lime Rock may be too short a distance with less variety of straights and corners). I'm sure Miller or Barber would do nicely too. They should be driven by two Cobra-experienced guys like McMahon and 3170 (there are plenty of others-I'm just talkin' here). Drivers should do fixed number of hot laps then switch cars. And do it often enough to get meaningful data.
My guess is that there won't be a significant difference in lap times and that subjectively, each driver will not find a 'nose heavy' (understeering pig) in the two.
Fire away.