Originally posted by Wolfala
For the early MIG29's that is true - they had a louver system that closed off the intakes and had air sucked in through the top of the LERX. However - in the later build MIG29's they discovered the ground clearence was enough that FOD wasn't a problem and eliminated the louver system.
Wolf
I never payed attention to the intake on the MiG-29s at the airshows

I read about this in popular magazine in late-80s...
Made some search, found out that the new intake design was used on MiG-29K, carrier-based version built for Tbilisi (Fleet Admiral of the Soviet Union Kuznetsov

).
Upper intakes were replaced with fuel tanks, but the intake protection was improved, at least it's what I have read
here.