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Cam,, Voodoo or somthing else
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chris989 View Drop Down
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Points: 63 		Post Options Post Options   Thanks (0) Thanks(0)   Quote chris989 Quote  Post ReplyReply Direct Link To This Post Topic: Cam,, Voodoo or somthing else
    Posted: Sep/16/2018 at 10:14pm
Hello all,
360,  11-1,
Edlebrock heads
lunati 10100702      .507"/.527"  220/226 @.050  262/268
air gap
MSD
ported manifolds,, soon to be headers.
bla bal bla

I am considering swapping in a different cam while I have the motor out for some other business.  the 702 grind runs out of steam ~5000.  I thought of going lunati 703 grind 527"/.547"  226/234  268/276 but with the heads,  they don't flow any more at .600 vs .500 of lift.   I see in the Isky catalog their 280 mega has a much lower lift (below .500).   

Any insight?? 

Thanks,
Chris
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danalog View Drop Down
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Points: 100 		Post Options Post Options   Thanks (0) Thanks(0)   Quote danalog Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2018 at 5:36pm
If you have edelbrock heads then I might suggest going with the edelbrock performer cam. I have heard great reviews on it and when I get the chance when the engine's pulled out, I might swap one in there. As for lunati, I have actually never heard of the brand before so I can't give you much insight on that. How much RPM are you hoping for?
1972 Javelin-AMX. 360-4v/727.
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motorhead_1 View Drop Down
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Points: 1007 		Post Options Post Options   Thanks (0) Thanks(0)   Quote motorhead_1 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2018 at 7:22pm
not enough info
how do you plan to use the car? street? strip? autox? parades?
tire size? trans?
do you need vacuum for power brakes?
call a cam grinder and get one tailored for you car the way you intend to drive it instead of off the shelf
69 SC/Rambler tribute 401/th400, 68 Rebel SST LSA, 66 F100 460/c6, 88 Merkur Xr4Ti, 71 Jaguar XJ6 LS1, 08 Supercharged Tundra
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jpnjim View Drop Down
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Points: 2752 		Post Options Post Options   Thanks (0) Thanks(0)   Quote jpnjim Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2018 at 7:24pm
Stock heads have a 30 degree intake valve angle,
Eddy's have a 45 degree.

The 45 degree angle trades some low lift flow for better high lift flow.

For that reason alone I'd want to go with a little more lift with the Eddy heads,
you sacrificed some low lift flow for high lift flow already,
you might as well use it.

Lower lift cams are generally easier on the valvetrain,
less wear and tear, less aggressive lobes, less spring pressure needed,
but the trade off is you're not getting all the flow you could be getting,
especially with our large .904 lifters that tolerate more aggressive lobes better than smaller diameter lifters.

Lunati makes good cams,
their Voodoo series uses modern, aggressive lobes.

I like their Street/Strip series, but they're not .904 lifter specific lobes.


Howards has a lot of AMC friendly lobes for decent prices as well.
Even a custom cam from Howards is inexpensive.
71 P-code 4spd Javelin/AMX
some Jeeps and some Fords
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Greyhounds_AMX View Drop Down
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Points: 1268 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Greyhounds_AMX Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2018 at 9:26pm
Does it need to run power brakes?
1968 AMX 390 w/T5
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chris989 View Drop Down
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Points: 63 		Post Options Post Options   Thanks (0) Thanks(0)   Quote chris989 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2018 at 10:17pm
thanks for the replies,

yes,, i do have power brakes.  The set up is in a cj7,  35 tires, 456 gears, 904 trans, and it is purely for fun, DD and some wheeling.  5800 rpm is about the most i would want to spin it.  

I guess a better question would be if anyone is running something like an Isky 282 /.517.    I spoke with them today and might go that direction.  
I don't need the extra lift if the opening event is equal in duration.  As in if an isky reaches .500 and stays open the same as the luntai,  I could care less if it continues to open even further. 
The heads have a diminishing return after .500
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 65 130 192 235 258 260 -
Exhaust 52 96 127 163 182 190 -


Considering Moab and Tahoe are hours of highway driving I am looking for something more forgiving on my valvetrain.  The .527 is about as big as i would like to go for that.  
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jpnjim View Drop Down
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Points: 2752 		Post Options Post Options   Thanks (0) Thanks(0)   Quote jpnjim Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2018 at 6:13am
Originally posted by chris989 chris989 wrote:

thanks for the replies,

yes,, i do have power brakes.  The set up is in a cj7,  35 tires, 456 gears, 904 trans, and it is purely for fun, DD and some wheeling.  5800 rpm is about the most i would want to spin it.  

I guess a better question would be if anyone is running something like an Isky 282 /.517.    I spoke with them today and might go that direction.  
I don't need the extra lift if the opening event is equal in duration.  As in if an isky reaches .500 and stays open the same as the luntai,  I could care less if it continues to open even further. 
The heads have a diminishing return after .500
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 65 130 192 235 258 260 -
Exhaust 52 96 127 163 182 190 -


Considering Moab and Tahoe are hours of highway driving I am looking for something more forgiving on my valvetrain.  The .527 is about as big as i would like to go for that.  

I agree that the Edelbrock heads level off at the .500 point (according to the manufacturer's info),
but 
the higher lift cams, .527", .540", .555", whatever are going to spend a higher percentage of their time above the .300-.400 range than the smaller cams that are under .500" lift.

You don't *need* .550" or whatever lift,
but that over .500" cam will be in the heads sweet spot longer than the .497 cam will be.

A nice, wide flat nose cam that peaks out at .500" would be great,
but most cams aren't shaped like that,
so the lower lift cams also have much lower lifts as you go down towards the base of the lobe.

Some more .050" duration over what you have now should do what you're looking for,
I just like the higher lift cams because they provide more lift everywhere throughout the duration of the cam.
71 P-code 4spd Javelin/AMX
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chris989 View Drop Down
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Points: 63 		Post Options Post Options   Thanks (0) Thanks(0)   Quote chris989 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2018 at 11:43am

[/QUOTE]

I agree that the Edelbrock heads level off at the .500 point (according to the manufacturer's info),
but 
the higher lift cams, .527", .540", .555", whatever are going to spend a higher percentage of their time above the .300-.400 range than the smaller cams that are under .500" lift.

You don't *need* .550" or whatever lift,
but that over .500" cam will be in the heads sweet spot longer than the .497 cam will be.

A nice, wide flat nose cam that peaks out at .500" would be great,
but most cams aren't shaped like that,
so the lower lift cams also have much lower lifts as you go down towards the base of the lobe.

Some more .050" duration over what you have now should do what you're looking for,
I just like the higher lift cams because they provide more lift everywhere throughout the duration of the cam.
[/QUOTE]

I spoke with crane this morning and like the others,  no one has profile number they are willing to share,   (lift @ .200/300/400/500).
I guess that would be giving away their "secrets".

I'm with you about the time under 500.   If the cam only spends 1 degree of duration at 500 the rest of the duration will not be in the heads sweet spot.  
 I will continue to look around,  it would be nice if they offered a duration @ max lift number to go along with the .050.

Chris
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Greyhounds_AMX View Drop Down
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Points: 1268 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Greyhounds_AMX Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2018 at 12:33pm
This should help - 

It's a graphical comparison of the combined cylinder head and cam capacity for each cam, and then the numbers below the graph indicate the difference in area under the curve between the two.

The Voodoo cam has a really aggressive lobe profile, so even though you're increasing the duration with the Isky 280 the overall flow area decreases by 1.4% on the intake. The exhaust area under the curve drops even more % because the Isky 280 is a single pattern cam, and the Edelbrock heads are tailored more for dual pattern cams with wider exhaust lobes.

You can see the overlap triangle in the middle is much larger with the Isky 280, so the rpm band will move upward as you wanted, though it might actually reduce the power output. 
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chris989 View Drop Down
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Points: 63 		Post Options Post Options   Thanks (0) Thanks(0)   Quote chris989 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2018 at 9:28pm
The graph is awesome,   Where did you find the info or software to imput the number?

Chris
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