[blykins]

I'd need to know what the heads flow, their port volume, etc.

LSA is based on what overlap the engine needs. Most guys want to go 112-114-116 because there's a lot of people on the internet that say the Webers need that.....and I wouldn't necessarily disagree on a street car.....but a road race car is completely different. Depending on the duration, you could end up on a 106, like a lot of the Shelby cars ran.

If you're wanting to save money by keeping the same valve springs, then I'd need to know how they're set up as well.