[Cliff R]

"Wow Cliff, those are some very impressive torque numbers for sure, who wouldn’t love that under their hood!"

It's also a back to back comparison, same engine, same dyno, same operator, so the information provides us with a DIRECT comparison between two different cams, or the "apples to apples" all the naysayers typically ask for with this sort of thing.

Another reason I put that information up here is detonation. With good flowing heads matched with small cams on tight LSA's one can very quickly raise cylinder pressure high enough to run into issues with lower compression builds. I build engines and tune for a living so get to see it first hand. The other information posted above is meaningless, IMHO. If you Google hard enough with anything you'll eventually find someone or something that agrees with your twisted line of thinking. So it isn't really DIRECT information, 2nd or 3rd hand at best and the poster had no dog in any of those fights, nothing to do with the build, didn't interact with the engine builder, customer or end user, etc.

Don't get caught up in all that. I've had more than one person bring a troubled 455 Pontiac build here that would NOT manage pump gas with the XE268 or XR276HR cam in it even though the static compression ratio wasn't that high. If you want details just ask, because I actually worked with those engines here. Several were brought from quite a distance after the owner exhaust all efforts locally to get them to work well.

The engine in the dyno charts I provided actually idled better with the larger cam on a wider LSA in it. This happens because the wide LSA reduces overlap, and more effective at cylinder filling at idle because there will be less reversion. Plus they were able to increase the base timing, which is HUGE for idle quality especially with lower compression builds.

I've built a number of 455 Super Duty and HO engines here with lower compression. The "mildest" of the bunch will make 1hp/CID without much effort and very tame. I attached a dyno chart/cam specs below from one I did here using a 230/236/112 HR cam and Harland Sharp high ratio rocker arms. It idled dead smooth clear down to 600rpms with only 12 degrees base timing in it. The compression ratio was only just a little higher than stock as I zero decked the block and had the heads milled slightly to straighten them up.

Even with the 281/287, 230/236, 112LSA roller cam in the big 455 it was done just past 5000rpm's, bringing us back to my first comment about the little 223/235/110 flat cam not making power to 6000rpm's like their advertising is telling us.

The last dyno chart posted was just sent to me recently from a customer that had me custom tune his carb for dyno runs. He built it himself with my parts but wanted me to check the work. that engine used dished pistons and early small chamber unported iron heads and lower compression. He used a 236/242 HR cam in it on a wide LSA...........Cliff