[Cliff R]

I'd say the most accurate statement made in the last dozen posts concerning the original topic was that the XE274 grind is better suited to the 400 engine than the 455.

I've seen that cam fair pretty well in a couple of 400 builds, but seldom in 455 builds.

The big 455 engines don't need short seat timing events, or tight LSA's with small camshafts. Those cams simply try to pull power down in the rpm range, and concentrate more of it in the mid-range.

The undersquare 455 Pontiac engine topped with cylinder heads no better than mid-level SBC's use doesn't want or need any more low end or mid-range power, or concentration of power earlier in the rpm range. They need to have the power spread out some, and respond well to cams a LOT of seat to seat timing, with some overlap and wide LSA.

We've seen this over and over again on the dyno, and with many street 455 set-ups. To date I've never once been the least bit impressed with a small/tight LSA camshaft, Comp XE or otherwise in a 455 street engine.

Every single time we stick a wide LSA cam in them with some decent off seat timing they tear your head slam off till you decide to move the shifter! Case in point, 455, KRE aluminum "D" ports, 230/236/114 HR camshaft.....502hp/599tq, never did quit making power till ya decided to shift it!

My old 455 engine with unported KRE heads and a Crower RAIV cam, 231/240/113, 494hp and pushed my daily driver car to 11.64 @ 116MPH in full street trim.

And yes, we used the crappy iron intakes and quadra-junks on both of those engines. We didn't dare put T-II's and AED's on them, we'd have got thrown off the track for running into the 10's!.....LOL.....Cliff