289 head bolt size; AFR 165\'s
What size are the heads bolts for 66 289 engine? I've ordered some 165 afr's that are drilled for 1/2" bolts or studs i assume. I thought the stock units were 7/16 but I'm not sure.
If the stock size is 7/16 then what is the best thing to do to make the new heads fit? I was thinking it was just a bolt on mod but is there any thing special you have to do to put these heads on a 289 engine. I know I'll have to get hardened pushrod's. What else??? Thanks
1965 Mustang 2+2:stock headed 289, Weiand 7515, Holley 600 dp, Tri-y's, 3.80 trak-loc, 4sp,Ram Air 13.83 @100.97
03 Mustang Gt d/d 13.58 @101.75