ARP Head Stud Kit Honda Civic Si B16 208-4601 ARP

Description:
It is for good reason that virtually every top professional engine
builder relies on ARP Pro Series head studs for their all-out
competition powerplants. Simply stated, there’s not a better stud setup
on the market today.

For openers, ARP uses a premium grade 8740 alloy that is rated far
superior to “aircraft” quality. Each stud is placed vertically in
special racks and precisely heat-treated to 200,000 psi. This procedure
ensures complete heat penetration and the results are far superior to
those lesser quality studs from other manufacturers who just dump pieces
in a basket and hope for the best.

Following heat-treat, each stud is centerless ground to make it as close
to perfectly concentric as possible. This procedure involves about ten
very slight cuts and results in an exceptionally straight part. It’s
important to note that lesser quality studs are not even centerless
ground – the material is thread rolled in bar stock form (mostly before
heat-treat, when the material is easier to machine). Because ARP studs
are manufactured to such exacting tolerances, you will note that gaskets
and cylinder heads literally glide into position and are perfectly
aligned – something that won’t happen with inferior quality head studs.

ARP studs are thread rolled after heat-treat, which gives them about
1000% (that’s ten times) better fatigue strength than those studs that
are threaded prior to heat-treat (a very common industry practice). It
costs a lot more to do it this way, because it’s tough on tooling, but
the results are well worth the extra effort.

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!

Premium quality heat-treated 8740 chrome moly steel head stud kits are
available for most every domestic and import applications.

You won’t find a better quality stud on the market from any other
source. Look for ARP stamped on each stud as your assurance of quality.

Clearly, ARP Head Stud/Bolt Kits are the best on the market today, and
the favorite of leading professional engine builders in all forms of
racing.

*HIGH PERFORMANCE SERIES*
High Performance head bolts are available with a reduced wrenching hex
or 12-point and wide area flanged head that eliminates the need for
valve train removal to facilitate cylinder head retorquing. All High
Performance Series bolts are 180,000 psi (which is 15% stronger than
Grade 8) and kits come complete with hardened parallel-ground washers.

*PRO SERIES*
All Pro Series bolts are cold-forged to ensure molecular integrity,
heat-treated prior to thread rolling and machining, and are rated
nominally at 200,000 psi. ARP Pro Series head bolt kits are application
specific – designed for use with typically competition only components.
These fasteners deliver superior strength and meet the ARP “ZERO defect –
ZERO failure” quality standard. Hardened and parallel-ground washers
are included with each kit to ensure even load distribution and accurate
torque readings. All Pro Series head bolts have a reduced wrenching hex
or 12-point head and wide area flange to eliminate the need for valve
train removal for cylinder head retorquing and permits the use of larger
diameter valve springs. Most applications have undercut short bolts
that can help eliminate head gasket failures through providing more
“stretch” to compensate for the additional compression of gaskets.

*Head Studs vs Bolts*
On many street-driven vehicles, where master cylinders and other items
protrude into the engine compartment, it’s probably necessary to use
head bolts so that the cylinder heads can be removed with the engine in
the car.

For most applications, however, studs are recommended. And for good
reason. Using studs will make it much easier to assemble an engine
(especially a racing powerplant which must be serviced frequently and
quickly!) with the cylinder head and gasket assured of proper alignment.

Studs also provide more accurate and consistent torque loading. Here’s
why. When you use bolts to secure the head, the fastener is actually
being “twisted” while it’s being torqued to the proper reading.
Accordingly, the bolt is reacting to two different forces
simultaneously. A stud should be installed in a “relaxed” mode – never
crank it in tightly using a jammed nut.

If everything is right, the stud should be installed finger tight. Then,
when applying torque to the nut, the stud will stretch only on the
vertical axis. Remember, an undercut shorter stud will have a rate
similar to a longer, standard shank stud. This provides a more even
clamping force on the head. Because the head gasket will compress upon
initial torquing, make sure studs and bolts are re-torqued after the
engine has been run.