[Cliff R]

Another board member went mid-11's with the XE274 in a 400 engine, still a very poor cam choice for a pump gas 455 build at any compression ratio, IMHO. Some guys just have cars that are very well set-up to effectively use the power they are making, so can run good numbers with those parts, or just about any combination of parts that make decent power.

I also have a customer that runs well into the 11's with a 455 using the XE-274 camshaft and iron heads. His heads are very well ported, and bowls "hogged" extensively and 45 degree seats. Compression is pretty high as well, and he uses stamped steel rocker arms and light valvetrain components. This really helps as it doesn't take nearly as much valve spring pressure to keep things in check and avoid "lifter crash" at high rpm's. So his 455 revs well past 5200rpms and makes good power with the heavily ported heads. We see most of the XE cammed engines go "dead" early in the rpm range, even the ones I've had on the dyno are DONE by 5000rpms or so. I attribute this to the ultra quick seating velocities, and harmonics that develope at high rpms as a result. Instead of trying "tricks" to get those cams to work, we just pick better cams right to start with, that don't require extra spring pressures, super light valvetrain components, 45 degree seats and heavy bowl work, etc.

These excellent results with XE cams NEVER happen with the smaller ones, and even with the larger grinds fall into the same catagory as the guy that runs into the 10's with a completely stock fuel system and stock mechanical pump. For every guy doing that deal, there are 30 guys that can't get out of the 13's trying to do the same thing........FWIW......Cliff

PS: NICE numbers on the W-72 stroker build!