In this months Chevy High Performance magazine, the did a spread on Gen III/Gen IV LS motors. They claimed that an LS1, with ported heads and upgraded camshaft can approach the 550 HP mark? Really? That's a 200 HP increase with just heads and cam. I know there are gains to be made with upgrades, but that seems pretty high. Someone educate me. Thanx.

That sounds about right. Nothing else in your motor aside from stroke is going to effect your hp gains in any sort of significant way. Top end puts the power out, bottom end keeps the power in. The cam is the heart of your engine and the heads are the lungs.

yep that's right. LS motors are awesome. Doesn't take much at all to put 450 hp to the ground.

Yes you can make that kind of power from a LS1 with ported Heads/cam package. I did a nice lil stealthy package for a customer that's dyno proven 440 rwhp with a stock type idle on a mild tune. But you have to make sure you tune them right.

Yes on the engine dyno. In the car you need all the supporting mods such as an excellent air intake system and exhaust. Electric water pump was probably used.

That was rear wheel hp on a Mustang dyno. It was a stock bottom end 2000 LS1, I used a BBK intake that I mildy ported with a stock water pump and ignition system, a 85mm Tb/maf, 1.75" headers with a custom dual termination box exhaust that has dual 3" bullet mufflers (too loud), a cam with only 218 degress on the intake and .558' lift with stock lifters and the ported heads with beehives. The car was fully equiped with ac and smog stuff and no underdrive pully and has a 3500 stall converter. It also passed the indiana smog test. So those things can make some power if done right. But I still like the older stuff cause its so cheap to build them.

"1.75" headers with a custom dual termination box exhaust"

Can you elaborate on the termination box. Pictures would be nice. Not much information on exhaust termination boxes in actual use.