just want some reassurance on combo choices

keep in mind soft ware predictions can be useful at showing trends,
but the real world has a well know tradition of making the predicted out-comes look rather optimistic or not following those predictions.
Ive run several of those cams (all but the isky) in my personal corvettes 383 sbc, you really can,t expect to see more than a 45-55 peak, hp swing,
between the mildest crane 119661,
through the crower 00471- all the way up to the crane 119651, but what is rather noticeable is the off idle and part throttle drive-ability
youll spend a great deal more time at below 3500 rpm, than above 6000 rpm in my experience.

http://garage.grumpysperformance.com/index.php?threads/my-current-corvettes-383-combo.430/

maybe its just because Im 70, but I know I have more than enough power with any of those cams, in a properly built 383-406, SBC,
to destroy the rear tires,and twist off half shafts, at will,
so I'm not all that concerned with having the last potential peak hp available.
Breaking driveline parts in a C4 Corvette is expensive.
All Race upgrades cost thousands for them as you know too.
$2 -10 k a pop.
 
Fine by me, but that pro Flo will only support 550hp. Looking forward to seeing what you come up with
Losing track what You actually want.
What likely is most important Now is Guarenteed High Intake Manifold vacuum.
14 to 18 inches at idle .
600-900 rpm range.
To work with the EFI system with Zero issues.
That leaves all High Overlap camshaft with 70-120 degrees advertised out worthless with EFI.
They all dislike erratic Map vacuum signals and if Mass Air Flow sensor even more sensitive.

Smaller duration cam is better with EFI.
 
What I want is guaranteed Power to outrun any Modern LS3 engines without Turbocharging used.
They can have a true 500 Hp on 87 octane gas.
Just 6.2 liters used.

Power to win street racing Hellcats.
But that's my own desire wishes.
Not yours.
 
Losing track what You actually want.
What likely is most important Now is Guarenteed High Intake Manifold vacuum.
14 to 18 inches at idle .
600-900 rpm range.
To work with the EFI system with Zero issues.
That leaves all High Overlap camshaft with 70-120 degrees advertised out worthless with EFI.
They all dislike erratic Map vacuum signals and if Mass Air Flow sensor even more sensitive.

Smaller duration cam is better with EFI.
I'd like to use the EFI, keep it street mannered Brian. No crazy cams. Need at least 10" vacuum. I can change injectors if need be. Don't lose track of I'm not trying to be an all out race machine with this. Good torque and go. Off the shelf parts. I don't have the patience and time to be building a set of custom 2" primary headers and trying to run 7500 rpm. If I did that I'd go solid roller anyhow
 
I have a stone age tech Olds 425 V8 engine in my 1963 Pontiac GP.
Put it together 3 years ago now.
Factory Powerhouse engine.
10.25:1 static compression.
Iron heads.
Factory 270 advertised duration cam.
I see 16-18 inches on the factory console vacuum guage.
Idles smooth.
Stomp on the gas it burns rubber.
Hooks fast.
Raced a C6 LS3 Corvette and hung with him to 120 mph on the highway.
Dinky cam by hotrod race standards.
 
I'd like to use the EFI, keep it street mannered Brian. No crazy cams. Need at least 10" vacuum. I can change injectors if need be. Don't lose track of I'm not trying to be an all out race machine with this. Good torque and go. Off the shelf parts. I don't have the patience and time to be building a set of custom 2" primary headers and trying to run 7500 rpm. If I did that I'd go solid roller anyhow
We ran into this issue earlier this year.
WE HAVE ZERO PROVEN WAYS TO PREFICT EXACT INTAKE MANIFOLD VACUUM.
TOO MANY VARIABLES EXIST.
 
I have a stone age tech Olds 425 V8 engine in my 1963 Pontiac GP.
Put it together 3 years ago now.
Factory Powerhouse engine.
10.25:1 static compression.
Iron heads.
Factory 270 advertised duration cam.
I see 16-18 inches on the factory console vacuum guage.
Idles smooth.
Stomp on the gas it burns rubber.
Hooks fast.
Raced a C6 LS3 Corvette and hung with him to 120 mph on the highway.
Dinky cam by hotrod race standards.
Maybe he missed a gear. Just kidding. You know what I'm saying about the cams, no crazy durations, no crazy overlap, I don't want it to not clear up until 3500rpm, needs vacuum. We had good candidates with the 5 we had. Pick a couple more you like if you want, throw them in there @.050 keep it the same induction system. 1.6 ratios, add mufflers and let's see where we end up
 
What I want is guaranteed Power to outrun any Modern LS3 engines without Turbocharging used.
They can have a true 500 Hp on 87 octane gas.
Just 6.2 liters used.

Power to win street racing Hellcats.
But that's my own desire wishes.
Not yours.
I own a car that I will race a hellcat with. Not looking for that in THIS car. The tubbed orange Camaro fits that bill. And it will embarrass a Corvette quite often
 
Maybe he missed a gear. Just kidding. You know what I'm saying about the cams, no crazy durations, no crazy overlap, I don't want it to not clear up until 3500rpm, needs vacuum. We had good candidates with the 5 we had. Pick a couple more you like if you want, throw them in there @.050 keep it the same induction system. 1.6 ratios, add mufflers and let's see where we end up
I'd like to use the EFI, keep it street mannered Brian. No crazy cams. Need at least 10" vacuum. I can change injectors if need be. Don't lose track of I'm not trying to be an all out race machine with this. Good torque and go. Off the shelf parts. I don't have the patience and time to be building a set of custom 2" primary headers and trying to run 7500 rpm. If I did that I'd go solid roller anyhow
You want more Intake manifold vacuum than Rick has with his 400 ci SBC Crower cam.
It will vary by Altitude you live at.
Where you drive through.
By weather conditions.
By Barometric pressure changes.
12-14 at least needed for Safe Zone EFI and allow 2-4 inches water depression manifold drop for and changes.

It does vary in my 63 Pontiac at different times of the year.
Watch that Guage all the time driving.
Always working with Engine running.

Surprised that C6 Vette owner.
Got a Thumbs up.
We were racing on Interstate 80 here in Illinois.
 
You want more Intake manifold vacuum than Rick has with his 400 ci SBC Crower cam.
It will vary by Altitude you live at.
Where you drive through.
By weather conditions.
By Barometric pressure changes.
12-14 at least needed for Safe Zone EFI and allow 2-4 inches water depression manifold drop for and changes.

It does vary in my 63 Pontiac at different times of the year.
Watch that Guage all the time driving.
Always working with Engine running.

Surprised that C6 Vette owner.
Got a Thumbs up.
We were racing on Interstate 80 here in Illinois.
I'm at normal atmosphere pressure here. No crazy elevations
 
We are back to square 1 again.
That is Ok.
It's a new challange.

Have to look at factory cams used in High po family sedans .
Modern EFI Cam profiles.
 
Right now I am going to say a 270 - 273 Advertised duration cam.
Somewhere with a 112 -114- 118 -120 LCA Lobe seperation angle required for EFI.
 
Not necessarily. That Straub cam is fine. That Crower would probably work. Unsure about the Crane's, that isky 272/282 would be fine. Run it like you ran everything else last night but at the .050 valve events and let's see what happens
 
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