Well, it looks like you got a big part of your issue discovered. Any idea what the timing (Initial and Total) was? Were you running premium fuel in it? I went back earlier and listened to the video, and I was thinking the timing might be off. As far as your question about cams, for a given cam lobe profile, a roller will generally run a little smoother than a conventional lifter cam. Problem is, the roller advantage also allows steeper ramps, and therefore longer duration events. This is one of the main advantages to running a roller cam, so you can be darn sure the cam grinders are going to take advantage of it. I've run the Ford Motorsports E-303 cam (M-6250-E303, 1985 and Later 302 Roller Cam, 1.60/1 rocker ratio, 282°Int. 282°Exh. Adv. Duration (220°Int 220°Exh @ .050), .498 Int. 498 Exh. Lift - NOTES: (1) On EFI engines, performance camshafts work only with mass air induction systems. Will not work with Explorer EEC-V EFI. (2) Also fits 1994-97 351W with factory roller cam when used with mass air EFI. (3)Stock 5.0L HO cam advertised specs are 266°/266° duration, 0.444"/0.444" lift. (4) May require piston modification for piston-to-valve clearance. Valve clearance should be checked. (5) May require longer pushrods. (6) Hi-Stall torque converter recommended for automatic trans.) on both carb and fuel injected apps, it idled noticeably smoother in an EFI motor. My recommendation is multi-part: 1. Have the builder cc. the engine and find the true static compression ratio, it may have been to high, causing the timing to have be retarded to try and keep it out of detonation. I'd go for between 9.0 and 9.5 with iron heads, 9.5 to 10.0 with aluminum. 2. Stay with the roller cam, but consider stepping down a size (or two). Maybe something in the 268° to 272° advertised duration. This is kinda going to depend on the answer to #1 above, but if your compression ratio was a little high, and you correct it, a little less cam will probably make more power with a better timing curve. Big cams are sometimes used to bleed off some compression (Goggle Static vs. Dynamic compression ratios for more info on this). 3. Carb size? With that big of a cam, I would have expected no less, than a 650 cfm carb, and possibly a 700 cfm, depending on the overall combination (Yeah, yeah.....I know what the CFM calculators say, but the optimum carb size for highest efficiency and the one for best all around performance are NOT one and the same). Carroll Shelby got away with running 1200cfm (!!!) on 302's for years, and they wern't exactly falling on their faces! ;-) For more theory on that, pick up a copy of David Vizard's "How to Build Horsepower Vol. 1" (I highly recommend it for a lot of reasons, this is just one). If the carb was a little small, it also "could" have been contributing to a detonation condition. 4 and 5 kinda go together...... The engines out, so now's the time to address those engine mounts, and think about a bigger stall converter (most street rod converters stall around 1800 - 2000 rpm, with the current cam, I'm thinking you need more around 2200 -2500 rpm). This would alleviate the creeping / impossible to hold back at a 1000 rpm idle problem you had before. I don't think you NEED a 1000rpm idle speed, but 800-850 probably would be appropriate. Bad thing about this is (the bigger the converter, the less efficient, and therefore) worse gas mileage.