86 bronco II cuts out

I have a 86 bronco II. It runs good when cold but when it warms up it starts cutting out and it dosen't rev up past 2000rpm and I only get 90kms/hr out of it. If anyone can give me advise on how to fix the problem it would be great thanks.

I would check your Rebreather System. There is most likely a computational problem- rather than a spent gasket. You may have lost a sensor along the way. Do you have a Computer Tester? They're invaluable if you love Fords with Computers...like my 2 Broncos, the BII, the 4 Tempos...(sheesh!)