For every 100lbs it is the same as 10HP.So light is a answer.Tons easier to lose 100lbs than pay for 10HP.Thing that honestly struck me when I read you wanted a N/A 10 second SBC is for the street light to street light racing,it doesn't account for you to really know what the other car is.A N/A or not.So what do you do???.Get out before the light changes and ask the other guy if he is playing by the rules with a N/A car.My point is the cars that are a 10 second N/A car on the street are rare.More likely more boost additive cars that are being sprayed in that 10 second bracket.And why worry about a 10 second car for the street when you know going in there aren't that many of them.
anyways.

The other thing is nothing changes.The old saying is how much money to you want to spend and how fast to you want to go??.With World Products big inch SBC's you might get close and then spray it to get you closer.But your going to paid to play there for sure.