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So I just had my 396 rebuilt and I am going EFI with a Holley Sniper, and I was going over the camshaft specs and now I'm a little worried.
first the N and the end of the spec is indicating Not Computer Compatible. Did some quick reading and now I'm even move confused.
from my reading it seemed to indicate that the vacuum too stable for the EFI to read making it harder to for it to calculate demand but then I also saw something about a big LSA and EFI being ok with that so I ended up more confused. the statments seem to contradict each other, im guessing i am miss reading/understanding something?

Also side note I'm pretty sure during the build process they told me the compression was going to be just a tick over 10.5:1 and again in the cam spec it specify's 9.5:1 still reading up on this, going to try a look up my pistons and try and figure out if what they told me is true.

Thank you
Current Engine spec should be 408 cubes with KB160 domed pistons 0.180in and 702 heads

713854
 

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So I just had my 396 rebuilt and I am going EFI with a Holley Sniper, and I was going over the camshaft specs and now I'm a little worried.
first the N and the end of the spec is indicating Not Computer Compatible. Did some quick reading and now I'm even move confused.
from my reading it seemed to indicate that the vacuum too stable for the EFI to read making it harder to for it to calculate demand but then I also saw something about a big LSA and EFI being ok with that so I ended up more confused. the statments seem to contradict each other, im guessing i am miss reading/understanding something?

Also side note I'm pretty sure during the build process they told me the compression was going to be just a tick over 10.5:1 and again in the cam spec it specify's 9.5:1 still reading up on this, going to try a look up my pistons and try and figure out if what they told me is true.

Thank you
Current Engine spec should be 408 cubes with KB160 domed pistons 0.180in and 702 heads

View attachment 713854
What is 106 and 114?

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I've been told with most EFI's, anything under 12 on vacuum requires tuning at light throttle at minimum.

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Ryan
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Unless I’m missing something, I don’t see why a sniper can’t handle that cam shaft. People in this site run larger cams in smaller motors with a sniper successfully.
If I had to guess, “not computer compatible” just means it’s not for emissions or stock tbi engines.

As for the compression: They’re just trying to say that they recommend at least a 9.5:1. Other wise the cam will bleed off enough cylinder pressure to feel a little lazy. Is this your concern? Or are you worried about compression being too high for pump gas? You might be in the edge depending on several other engine specifics.
 

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Unless I’m missing something, I don’t see why a sniper can’t handle that cam shaft. People in this site run larger cams in smaller motors with a sniper successfully.
If I had to guess, “not computer compatible” just means it’s not for emissions or stock tbi engines.

As for the compression: They’re just trying to say that they recommend at least a 9.5:1. Other wise the cam will bleed off enough cylinder pressure to feel a little lazy. Is this your concern? Or are you worried about compression being too high for pump gas? You might be in the edge depending on several other engine specifics.
I concur...

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That's a tiny camshaft for a 408. The only negative is the tight LSA, but the cam is not that big so it shouldn't be a problem. The cam in my 427 is 274/286 @ 0.050", it idles with 4" of vacuum and it has EFI.
 

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It’s likely to need to be tuned at idle, Sniper might not be able to handle that by itself. It will be very reliant on the IAC, so make sure to read up on proper iac procedures
 

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Yup it is the same cam as a zz502.

I run a zz502 cam in my 540 with sniper.... no issues at all. Auto program in a street/strip setup and it will be slightly rich to start.
 

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"What is 106 and 114?"

Intake lobe 106, Ex lobe 114,..so we'd call that a "110 LCA" cam. Someone correct me if I'm wrong on that. Overall, that cam does't appear too radical for EFI, but I'm no expert.
 

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"What is 106 and 114?"

Intake lobe 106, Ex lobe 114,..so we'd call that a "110 LCA" cam. Someone correct me if I'm wrong on that. Overall, that cam does't appear too radical for EFI, but I'm no expert.
It's a 110. Intake plus exhaust, divided by 2 (IC+EC)/2=LSA

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Computers dont care about the camshaft. EFI's with multi port injection prefer straight duration cams as opposed to carbs which like split duration cams.
 

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Computers dont care about the camshaft. EFI's with multi port injection prefer straight duration cams as opposed to carbs which like split duration cams.
Computers care about 02 sensor readings, which camshafts are a variable.

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Self learning EFI's dont like a lot of valve overlap, as it reduces the vacuum signal at idle.

Thats a non issue if you are programming your efi.
 
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