If you need to performa a function, wait, and perform it again, here's a nice loop to help with that.

rateLimiter.js

function rateLimiter(thisArray, callback) {
	var count = 0,             // Loop count
		rateNum = 10,      // Items per loop
		rateTime = 5000,   // Time between loops
		items = [];        // Temp array
	var batches = thisArray.length / rateNum;

	function splitArray() {
		items = thisArray.splice(0, rateNum);
		console.log('batch ' + (count + 1) + ' out of ' + batches);

		// Insert function here on var "items"
		items.map((f, x) => {
			magicMap(f);
		});
		// Insert function here on var "items"

		setTimeout(() => {
			count++;
			if (count < batches) {
				splitArray();
			} else {
				console.log('process complete');
				if (callback) callback(null, true);
			}
		}, rateTime);
	}

	splitArray();
}