Have a 98'gtx ltd that tops out at 6000rpm if im lucky carbs and raves have been cleaned maintenance codes have been cleared still tops out at 6000rpm any ideas.  thanx  also have checked its fuel lines are black i think it should be about 7000-7200 rpm it used to due over 60mph easy
				
			 
	


 
 
		 
 
		 
 
		 
 
		