cam timing confusion! help please!

[Dr. Paradox]

Hey everyone, I've got a 305 that I built about 2000 miles ago that I'm trying to figure out what I think is a cam timing problem

it's standard bore 9.5:1 compression 187 casting heads TBI
(soon to be crossfire as soon as I get this figured out)

I put the comp cams 12-304-4 which is supposed to be a really mild lift super low end torque cam that is very computer compatible.

the problem is that it tries to lope a bit at idle and the computer hates that and goes crazy (did some prom burning and made it a lot better but not perfect)
the thing I'm noticing is that it has no power until it revs to like 3500 and up
which is totally not what this cam is supposed to be for.

I measured it with a degree wheel and got even more confused.

intake centerline measured 109* it's supposed to be 107*

intake .006" open measured 10* it's supposed to be 16*

yes, I measured before my lifters leaked down so that isn't the problem

I measured it exactly how comp cams says to.

why would these two specs be different amounts off?

it is 2* retarded on centerline and 6* retarded on opening

would that be enough to cause my engine to run completely different?

how much should I advance my cam?

 

[Jims86]

Hey everyone, I've got a 305 that I built about 2000 miles ago that I'm trying to figure out what I think is a cam timing problem

it's standard bore 9.5:1 compression 187 casting heads TBI
(soon to be crossfire as soon as I get this figured out)

I put the comp cams 12-304-4 which is supposed to be a really mild lift super low end torque cam that is very computer compatible.

the problem is that it tries to lope a bit at idle and the computer hates that and goes crazy (did some prom burning and made it a lot better but not perfect)
the thing I'm noticing is that it has no power until it revs to like 3500 and up
which is totally not what this cam is supposed to be for.

I measured it with a degree wheel and got even more confused.

intake centerline measured 109* it's supposed to be 107*

intake .006" open measured 10* it's supposed to be 16*

yes, I measured before my lifters leaked down so that isn't the problem

I measured it exactly how comp cams says to.

why would these two specs be different amounts off?

it is 2* retarded on centerline and 6* retarded on opening

would that be enough to cause my engine to run completely different?

how much should I advance my cam?

Is this for the Truck, or for the Firebird in the Pic? I would say intall it straght up with the Timing cog index marks. TBI is really finiky when it comes to cams....well, and Speed density efi is.
I had a problem with my Com 12-388-4 in my TBI 350. It lowered the Vacuum enough to cause it to run pig rich, and it surged really bad at idle. You will need to have a custom chip calibration done.
Also, I would strongly recommend staying away from the crossfire injection...the Manifold ports are extremely smaller that the standard ports on an SBC head.
TBI, TPI or a Wieand crossram would be better.