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I decided to move forward on a "beater" motor for my '68 Bee and stash the original 383. I had another '68 383 block laying around so I dropped it off at my not-so-local anymore machine shop back in the high desert. Another moparts member made me a great deal on some .030 1.320 CH Diamond pistons, I picked up some BBC 6.700 K-1 H-beam rods on clearance from Wiseco, and ordered a 3.915 B-Motor crank from 440 source. I plan to run Eddy heads so this setup will yield 451 cubes at about 10.5 compression. I want to keep a somewhat stock appearance so I plan to run the factory HP exhaust manifolds and 2.5" factory style 440 exhaust. The 383 had a Performer RPM and an 800 Edelbrock AFB so I'll be swapping that setup onto the 451. A fresh coat of turquoise paint and a 383 pie-tin will go a long way to hide the true nature of this motor.

Question is, is there a better "manifold" cam out there than the old .528 MP solid? I know Andy's "manifold" 471 ran best with that cam & this motor is really just a smaller version of his 471. That was a few years ago, has anyone actually run something that works better?

FWIW Gears are 3.73 & I plan to drop the 3000 converter to about a 2500 converter

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After reading and re-reading Andy's "Lobeology" article and talking to Dwayne Porter a couple times, I'm contemplating going with a custom Comp grind for my 383/451 to try to improve on the MP .528 cam, maybe get a little more lift & get the lash down to the .016-.020 range. One option is to run a comp xs-282s solid on 112 centers. Another thought was to run a pair of comp 6581 MM lobes on 112 centers. The "net lift" specs with 1.6 rockers are as follows:

MP .528: 241/241 .535/.535 112 Lobe centers
Comp 6581/6581: 239/239 .557/.557 112
Comp xs282s-12: 244/252 .537/.561 112

Anyone run the XS282s with manifolds?
Do the MM lobes survive on the street? I was planning to run EDM lifters, is nitride required too?

Or am I overthinking this?

FYI-For heads I'm going to run Porter Racing prepped Stealth Heads so I can have straight plugs.

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Questions / comments:
1. What did Dwayne P. suggest? And are you second-guessing him?

2. I'd be hesitant to run MM-type lobes w/o both EDM lifters AND nitriding... and I'm not so sure they'd be the right choice for an engine getting a lot of street miles. Something milder will be kinder to your valve springs, etc., over time.

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Questions / comments:
1. What did Dwayne P. suggest? And are you second-guessing him?

2. I'd be hesitant to run MM-type lobes w/o both EDM lifters AND nitriding... and I'm not so sure they'd be the right choice for an engine getting a lot of street miles. Something milder will be kinder to your valve springs, etc., over time.

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The motor will respond nicely to faster ramps. It is just a trade off on valve train abuse and running closer to the edge. There are several profiles between the XE and MM profiles in aggressiveness, but most are recommended to have direct face oiling and nitriding.

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what about angle plugs and cast exhaust manifolds?

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......but it's not clear to me that the extra expense of a custom solid or roller will buy much, if any, improvement in performance .

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Questions / comments:
1. What did Dwayne P. suggest? And are you second-guessing him?

2. I'd be hesitant to run MM-type lobes w/o both EDM lifters AND nitriding... and I'm not so sure they'd be the right choice for an engine getting a lot of street miles. Something milder will be kinder to your valve springs, etc., over time.

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I don't consider weighing the facts as 2nd guessing. You make a good point about wear & tear. Sounds like if I want to do something like option 2, I need to talk to Dwayne about a street roller but Andy Fs testing showed that more is not always better in this case. I have no doubt that Mr Porters recommendation will perform well but it's not clear to me that the extra expense of a custom solid or roller will buy much, if any, improvement in performance .

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Exhaust manifolds are restrictive and make cam selection even more critical IMO. Too much overlap (whether the result of tight lobe centers or fast ramps) causes excessive reversion that hurts torque.

Faster ramps are not always better, dual pattern cams are not always better, and unless your heads flow a lot at high(er) lift, the benefit of a street roller over a good solid flat tappet can be minimal.

And tell Dwayne I said "Hi" when you call him next time.

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I agree totally. Andy F's article clearly demonstrated that when it comes to a manifold engine, limited overlap and fast ramps are about the only things that made a real difference, and even then only a couple of the custom cams were marginally better than the .528. And the smaller Racer Brown cam was surprisingly close to the .528 with great punch at lower rpm.

Then when you look at Keith's "Fading Color" article, only 1 solid offered a substantial power increase over the MP .590 with fairly minor variations of lift/duration. This leads me to the conclusion that all of these customs might offer marginal gains ( or losses) until you hit that "sweet-spot" of lift, ramp, duration, & lobe angle where respectable gains can be had.

Problem is since every engine combo is slightly different, finding that "sweet-spot" requires either previous experience with a given combo or a wad of cash & a dyno. Obviously Dwayne, Andy (and others) have plenty of real life experience with similar setups to mine, I'm sure either of their recommendations will work well. Just trying to arrive at the best possible choice when its time to pull the trigger next month.

Thanks for everyone's help.