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Your recipe

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 11:08am
What roller cam Tom?
Cannot find an off the shelf roller camshaft that fits the factory iron heads to provide the 450 HP goal. Not without a 6500 to 7000 RPM top end, which is a very poor bottom end. 
The head flow is the ceiling on building HP unless you get the iron heads ported, which pretty much equals buying Edelbrock aluminum if not doing this yourself.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote wrebelmachine Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 11:28am
custom would be the way to go. But for off the shelf an old school herbert would work.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 12:29pm
Just crunched the numbers with the Herbert CA6K roller camshaft and 502 stock heads.
360 HP @ 4250 RPM.
Not near the recipe requested. 
More head flow required to utilize any camshaft above 0.480" to 0.490" of lift. Mathematically, this is the break even point on stock heads.
There are always exceptions with real radical lifts and higher RPM's. But from a cost perspective, these don't make a lot of sense unless your building for a specific purpose.
And the CA6K is a pretty radical lift at 0.624/0.640" and is choked off by head flow. It cannot even reach it's designed higher RPM levels.
A custom roller, possible, but unless we can see the numbers, wouldn't hold my breath:) 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rsrguy3 Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 1:43pm
This is fascinating, the factory number for hp in 71 was 350. So they designed it to its full capability and potential that year? If that's the case, man, that's just stupid cool.
 I really only care about the torques. I intend to run it as is until winter and then start sourcing parts, heads first. 
Tom, 
Does a complete rtr roller kit exist or do I need to source parts individually? 
javguy
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Post Options Post Options   Thanks (1) Thanks(1)   Quote jcisworthy Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 2:00pm
With 10:1 compression and a 215 @ .050 cam or bigger, air gap, torker, or vr jr intake, headers with a real good set of heads you can hit the 450 hp  / 500 tq goal

The smaller the cam the more head work you need to have done to get there 

I listed a 215 @ .050 because you say you are looking for lots of low end torque 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 3:33pm
Originally posted by rsrguy3 rsrguy3 wrote:

This is fascinating, the factory number for hp in 71 was 350. So they designed it to its full capability and potential that year? If that's the case, man, that's just stupid cool.
 I really only care about the torques. I intend to run it as is until winter and then start sourcing parts, heads first. 
Tom, 
Does a complete rtr roller kit exist or do I need to source parts individually? 
Factory hp number was 330 in 1971.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WesternRed Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 6:13pm
This is the smallest roller in the Comp lineup, 0.513" might just about work with factory heads: 

I've finally given up drinking for good...........now I only drink for evil.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 7:35pm
Looked at that, just before cooking supper. Have not crunched any numbers, but believe that that cam would be close to 420 HP with factory heads, 9.5 SCR, premium pump gas and OP's other pieces.
Will be tomorrow at best to do the math, which is always on the edge of true performance. 
The dyno or track times are the only measurable facts.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rsrguy3 Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 8:07pm
You guys are great. It's good to have this thread to look forward to, today was rough but also good, bitter and sweet.
I'm not tied down to just what I have as a base. I'm truly interested to understand what you gents would do for yourself if you were starting with just a 401 block and factory forged crank. 

What's a sensible power target for a regularly driven street motor? 
javguy
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PROSTOCKTOM Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 9:02pm
Originally posted by WesternRed WesternRed wrote:

This is the smallest roller in the Comp lineup, 0.513" might just about work with factory heads: 


That would be a nice little cam, but I would probably order a custom grind with a touch more duration it were mine. I have a stock Ford 302 GT40P long block from a 2003 Explorer that I added Performer RPM intake, 600 Holey, along with all the typical hot rod pieces. I installed a Ford Motorsports F303 hydraulic roller cam that specs 226/226 @ .050" duration, .512"/ .512" lift. This is a very well behaved street engine in a 1980 Fairmont Futura. Judging from the way it drives and pulls I wouldn't hesitate to use a similar profile in a 401 street engine. 

Tom
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