Before you install the studs, be sure there is adequate counterbore in the heads to accept the ARP studs. Often, at least with ARP, the unthreaded portion of the stud is longer than necessary and can interfere with proper torque, even with guide plates. The stud will try to pull the threads out of the head when the unthreaded part of the stud gets torqued. Ask me how I know . . . . .
Not familiar with the CHI head and its counterbore, but worth checking out.
Also, if you do not put enough torque on the studs, whenever you adjust valves you will need to place a wrench on the stud nut to keep it from backing out. Again, ask me how I know . . . . .
I decided that the common .750" base thread length of the stud, minus the .110", and also minus the .040 or so counter bore leaves very few threads to screw into the raw aluminum head (one without heli coils.) My solution was to purchase the 1.6" base stud length big block chevy exhaust studs and cut them down for proper length. In my case, I gained an additional 3/8" more depth in the head. Oh, I still had to helicoil the 3 holes that I over torqued due to incorrect counterbore . . . .
65' STANG, 3160 lbs
393W NA, 2.78 Toploader 4 Spd, 9" 3:70 Posi
Pro Comp Heads, Vic Jr. Intake, 750dp, CI Custom SFT, 10.2 CR, 1 3/4" Headers, Lakewood, Subframes, Caltracs
[ This Message was edited by: dennis111 on 2/21/07 6:55pm ]