So I'm ordering a few things from Summit and decide to go ahead and order headstuds while I'm at it. I look them up and two choices come up for 7mgte; head stud kit, and 12-Point Nuts w/ Undercut Studs. What exactly are undercut studs and what's their benefit? I'd like to know before I choose.
punkybooster89t
The undercut has to do with the diameter of the fastner, you can go to arp-bolts.com and find it described. I think it only applies to bolt applications.
Hehe, you would have thought that with all the places I looked for info that I'd tried arp's site itself. Thanks glntom! 
This is what they say about undercut studs if anyone wants to know.
"You will also note that ARP® offers specially undercut studs for several engines. This procedure (done only to the shorter studs) more equalizes the “stretch” of both studs, which makes for a more consistent clamping force—and one that compensates for head gasket compression when the cylinder heads are installed. This helps prevent blown head gaskets, and assures optimum engine sealing!"
This is what they say about undercut studs if anyone wants to know."You will also note that ARP® offers specially undercut studs for several engines. This procedure (done only to the shorter studs) more equalizes the “stretch” of both studs, which makes for a more consistent clamping force—and one that compensates for head gasket compression when the cylinder heads are installed. This helps prevent blown head gaskets, and assures optimum engine sealing!"
I had a set of undercut, sold them with my car, but from the reaseach I've done they are the way to go with aluminum heads.
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
