Cal35
New Member
I just installed my gt40 heads and 1.7 rockers on my 1995 mustang. haven't upped the timing yet, but there seems to be a loud knock right under the valve cover on the driver side. I checked the clearance on the rocker arms and stock valve covers, and they clear. anybody have any input. I know the roller rockers make some noise, but this seems a little too loud. let me know what you guys think. thanks.