Head Studs

Finally finished my measurements for the block and heads.  ARP (Automotive Racing Products) is well known for strong studs and bolts for racing.  I have ordered few custom set of head studs specifically for the 1UZFE.  Lt discuss individual parts in details.

Block:  The OEM head bolts screw in about 2".  Those head bolt are stretchable with 12mm hex.  Each block have 10 bolts.  5 on the top row and 5 on the bottom row.  The top row holes also have two holes that allow head guide.  The total depth of the block hole is about 2.5", I am not sure if there are thread all the way down to the bottom of the hole.  The block receiving end has 3/16" with smooth surface with out thread.  This great place for the studs to bottom out.  With the new studs coming in, we will be using only 1" thread on the block.

Heads:  There two row of bolt patterns for the heads.  Top row and bottom row.  Top row is measured at 2.7" from the beginning of the head hole to the bottom of the head.  Basically, its head depth length.  The bottom holes are measured at 2.5".  Its slightly shorter.  The bolts/nuts are sit deep into the head.  There are about 1.5" clearance.  Basically, there are much room for the nuts, but clearance for the cams become a problem.  I have done the following measurements.

Block: 1.40" (1" for studs, .4" has not thread) However, the block threads has about 2.5"
Gasket: .10" (actually its .093") stock is .051"
Head: Top row:2.7", Bottom row 2.5"
Washer: .20"
Nut: .50"

Total Required: 4.9"

Studs Length: 5.1"

The total is length required is 4.9" and the studs are 5.1" In order to make these studs. ARP asked me to send in a sample OEM stud and give them the above measurements. FYI, the top row of will require a .25" longer. The thread that goes into the block will be the sample. Here is the link on ARP Studs.  However, the thread in the nut part will fine thread for fine adjustments. They are available now if you are interested.  These are custom production and its only available via Lextreme.  Special instruction will come with the studs.