I love the way my boat rides with the SBC in it, but I'm thinking about a HP500. Is it possible to make a HP500 Carb weigh close to a SBC? I boat in fresh water only. If I swap out the factory iron heads with aluminum ones how much weight will it drop? I believe the HP500 already has a aluminum intake. What about the exhaust, is it iron or aluminum?

Is your SBC all stock with cast iron intake, heads, and exhaust ?

All stock except for edelbrock performer EPS aluminum intake, still has iron heads and stock exhaust, the iron log manifolds. Circa 1981. Was thinking about an intake, cam, aluminum head and aftermarket exhaust rebuild on the small block but now and considering a HP500 since a few have come up for sale. but wanna see how close I can get the weight.

About the only places to shave some weight is going to be aluminum heads and a crossover kit to eliminate the cast water pump

Maybe build a stroker SBC?
That said, the 24-7 hull has been home to lots of BBC engines. Hard to beat the torque a big block makes.

A lot of 24 Outlaws and 25 Active Thunders with Big blocks that run very well. Maybe there are other things (weight) you could move forward for better balance?

I'd be leaning toward an LSX powerplant.

Yep what he said ^^^^

If this is a 24/7, why do you want an anorexic boat? The weight on a short straight bottom will help the ride. If you have your heart set on light, go with the LS platform.Its easy to get more hp than a blue hp500

I second that motion.