I'm not one of the experts here, but just thought I'd chime in anyhow. If you got enuff CR the "041" cam with Rhoads lifters is a real good cam for a 455 Auto, with stock converter.
We ran this combo in several 455 bracket engines over a period of many years. With the Rhoads lifters, they idled smooth enuff for us to launch from an 800 rpm idle with a stock 13" converter. We were not going for max hp, or ET, so we shifted at 5000rpm. So, for idle to 5000 rpm operation, I couldn't have asked for anything better.
Would our cars have run quicker with bigger cams ? Certainly. Later on, a track we ran, switched to 1000ft, instead of 1/4 mile, and they set the minimum for Super Pro bracket at 9.99. We were running 10 teens. So I switched from 4.11 to 4.88 gears and switched to a CC cam with 244/253 @ .050 dur and just over .500 lift, and of course, Rhoads lifters. Still had a TH400 with stock 13" converter. Still left from an idle, cut good lights, ran 60ft times in the 1.60's, and ran a 9.85.
CC still has these lobes available, but only in single pattern cams. I'm sure they'd grind a custom dual pattern with these lobes. But I'm thinkin these lobes may need a bit more than 9.5 CR to work well. We were running the '68-'70 big valve heads--16, 62, 64. I have not done any cam testing like these other guys have, so I'm sure they would know if these lobes are usable or not. With today's technology, there are probably many better lobes available.
http://www.summitracing.com/parts/cc...w/make/pontiac
http://www.summitracing.com/parts/cc...w/make/pontiac
http://www.summitracing.com/parts/rh...w/make/pontiac
Cliff has done LOTS of testing with the 041. I think he used the Crower 60919. I used the Crane and Melling versions, because they were cheaper at that time. The Melling SPC-8 is still only about $100 on Ebay. Jim hand wrote one of the best articles I've read on using the 041 cam and Rhoads lifters.
http://community.fortunecity.ws/silv...build/cams.htm
Hey, all I'm sayin is that the RA4 cam with Rhoads lifters worked great for us, for what we were doing, and helped us win lots of races. I'd like to hear from the experts here, at exactly what CR the RA4 cam becomes "not so good". Like, will it work OK at 9.5 but not too good a 9:1 ? I assume there is a CR number, below which, it is a bad choice.