Review on 🚀 COMP Cams Xtreme Energy 250/256 Hydraulic Flat Cam for Pontiac 265-455 by Srinivasan Bennett

The camshaft itself is awesome. Loads of power with terrible throttle response, incredible midrange power and really choppy idle. My problem was developing the rest of the kit. First, the valve springs have over 200 pounds of spring pressure when closed and 420 pounds of spring pressure when open. You'll never want to weigh more than 120 pounds on a 400 Pontiac Street/Strip Hot Rod. Pressure closed and 320 open. A little more and you'll wipe the cam and knock the valves out of the heads. Do you wonder why so many cameras are deleted? That would be a HUGE reason why! Second, out of the 3 springs, a flat coil will mesh with this cam when fully raised. Another big problem. Coil springs and 420 pounds of compression equals engine failure. The recommended tappets were .020 too long and held the valves open. If the valves don't close, there is no compression and the engine won't start. So I ordered the correct length bars, new 120lb. valve springs and built a vicious running engine! And I mean bad! BUT, if I just threw this kit in this engine and started it, one of two things would happen. It would either not start or, if the recommended pushrods were the correct length, would catch fire and self-destruct. Luckily I'm a 30+ year automotive veteran and I've been in the past and know how these engines should be tuned! THE COMPANY needs to rethink the design of this kit and stop treating Pontiac engines like BBC drag engines. They are not the same! It's impossible to tell how many Pontiac engines died horrible deaths as a result of terrible engineering. I'm afraid to think I sincerely hope they revisit this set and get it right. BTW, if you omit the flat coil spring and just use the other two, you'll end up with 140/340 spring pressure. It's still about 20 pounds tall but will work. You want to use really good oil. I use Valvoline Racing High Zinc 20w50. In all these years he has never let me down. And at that pressure, the valves shouldn't float even at 6500 rpm, which is good! Did I mention it's an evil camera? The elevators are also well American made. I was glad to see it! :)