I picked up a 350 motor, has 882 heads on it (I know they are not great will switch over to vortecs in the future with a different intake). the motor came with an edelbrock victor jr intake manifold planning to go with the summit racing .450 lift cam and lifter set https://m.summitracing.com/parts/sum-k00172, car has headers 2.5 inch exhaust and a flow master muffler. Going to keep my quadrajet if I can find someone to tune it right otherwise will switch to a 650 holley carb. motor is bored .010 over
I was told this intake will run like crap on this build but it is all I have at the moment should I bother putting it all together or will it truly run like ****?

 

You have a few issues and most of them seem to be from mismatched parts being used to save costs.

Without knowing that 350 you have or what pistons were installed I would guess you are around 8.5:1 static compression but it could be as low as 8:1. That cam will work but will by out of power before 5500. I would upgrade springs while you are at it and freshen up anything that needs it in the 350. Probably put in a new double timing chain cost < $30

The manifold won't fit under the hood and will require a spread bore to square adapter plate. It is designed for high revving engines 3500-8000. You will loose a lot of low end torque. I would look for a RPM performer in the carb style you want.

Your exhaust at 2.5" is too small I would upgrade to 3" with a better muffler. I would bet the headers are flotek or some other similar clone? Those are not that good for power same with their Y pipe.

If it was my car I would finish the exhaust correctly and put the 350 on a stand and build it correctly.

 

previous owner "says" it is at 9:1 compression

 

Probably the least of your concerns, put it on a stand and pull the valve covers and a head, check what is installed and go from there. 882 heads have 76cc chambers so it might have domed pistons to get up to 9:1