I have a 1990 cherokee 4.0 and i want to get rid of the bull crap vacuum system on the air box to put an intake on but i want to know if the vacuum is that important to the driveability of the cherokee

 

Chances are it wont do much harm. Changing the intake wont stop it from pulling air in.

 

All of that vac crap you are referring to is emissions stuff, and some of it may well be important. What intake are you looking at putting on, if it's later than a 90 there is no provision for an EGR valve. I have no idea how it will run with all of the hoses and EGR removed, or what the gas mileage could do, but I know here in Cali it's a no-no.

 

I understand it is emission stuff and i realize i need the EGR and everything but can i remove the factory air box and put an open element cone filter with intake tube on it... I have done this with all of my newer cxars and it has been just fine but i dont know how sensative the jeep is to all of it

 

The emission hoses need a place to draw clean air from. Losing the preheat stuff shouldn't be an issue, but the bigger hoses on there are important.