When i get to about 4k rpm the battery light comes on and my lights start flickering the car trying to turn off... brand new alternator and new batterry..

Car is a 1990 crx with obd1 conversion D16z6 turbo

 

Check the battery posts, it sounds like they are grounding out on something. I had a similar thing happen in my CRX a long time ago, turned out the positive terminal would randomly touch my intake tube which would then spot weld to my hood, lol.

 

I was just going to say I had similar issue and it ended up bing the alternator.

Get a dvom and test your circuitry.

 

shorting a positive cable somewhere

 

Your "brand new alternator" is a dud.

Get it replaced.

 

agreed.

 

second that.

just last week i replaced the alternator in my dad's work van, first one they pulled off the shelf tested bad out of the box

 

either alt is bad, or the belt is slipping at higher rpm's.. you get it on there nice and snug?