Im curious to find out what size diameter rod bolts that the ARP's are which are fitted to the Eagle rods. the Eagles i put in a DSM used bolts that appeared to be 8mm, but i cant be sure. i know the stock 7M bolts are 10mm diameter, so i just wanted to find out if the 7M rods and 2jz rods are at LEAST 10mm shank diameter. if they are, it will alleviate my concerns.

Chris,

The bolt diameter for the 7M rods are 3/8" (9.5mm). ARP bolts are used as the primary fasteners for their rods.

what ive heard from builders is that Eagle uses the same size rod bolt in all their import rods, from the Honda motors, Mitsu motors and our motors. so while the EAgle rods would be great for 500 horse hondas, im not sure itd handle 1000hp supras? any chance that someone in the warehouse can compare the H22A rod to the 2jz/7M rod... or would torque freaks know this?

Very interesting, seriously.

Well, from what it looks like, all of their import rods now come with 3/8" ARP 2000 Rod Bolts. Some of their domestic applications (ie. Ford Flat head) come with the 5/16" ARP 8740 capscrews. With the flat heads, they're running those rods and bolts up to 750hp. With the ARP 2000 bolts in the imports they're rating the assembly at 900hp on the 4 cylinder applications and up to 1500hp on the 6 cylinder applications.

Hey josh... after doing some research, my fears were confirmed. turns out that the ARP2000's are almost scraping the bottom of the barrel as far as ARP's inventory goes. seems like they are assuming we wont make real horsepower with the rods they sell. i found this after a breif search on SF. as it turns out, the ARP2000's that are fitted to the import rods, off-the-shelf are only ONE step up from the bottom grade bolt: 8740 Chromoly bolts. If i end up getting a set of rods, i may end up having you custom set of Eagles fitted w/ either Aermet 100 or CustomAge 625+ bolts for the 7M. with those bolts i should be able to hit my 1000rwhp goal and rev to 7500+rpm w/o hesitation. check out the info that i found. others may find it useful too.

O.k. I did some reasearch directly from ARP's website:

MATERIALS USED IN THE MANUFACTURE OF CAP SCREW TYPE CONNECTING ROD BOLTS

8740 CHROME MOLY: Until the development of today’s modern
alloys, chrome moly was popularly considered a high strength material.
Now viewed as only moderate strength, 8740 chrome moly is seen as a good
tough steel, with adequate fatigue properties for most racing applications,
but only if the threads are rolled after heat-treatment, as is the standard
ARP® production practice. Typically, chrome moly is classified as a
quench and temper steel, that can be heat-treated to deliver tensile
strengths between 180,000 and 210,000 psi.

AERMET® 100: With a typical tensile strength of 280,000 psi, Aermet
100 is a new martensitic super-alloy that is stronger and less expensive
than the super-alloy austenitic materials that follow. Because it is capable
of achieving incredibly high clamping loads, it is ideal for short but
extreme environments like top fuel, funny car and some short track
applications. Although Aermet 100 is a maraging steel that is far superior
to other high strength steels in its resistance to stress corrosion, it must
be kept well-oiled and not exposed to moisture.

ARP2000: An exclusive, hybrid-alloy developed to deliver superior
strength and better fatigue properties. While 8740 and ARP2000 share
similar characteristics—ARP®2000 is capable of achieving clamp loads
in the 215,000-220,000 psi range. ARP®2000 is used widely in short
track and drag racing as an up-grade from 8740 chrome moly in both
steel and aluminum rods. Stress corrosion and hydrogen embrittlement
are typically not a problem, providing care is taken during installation.

L19: This is a premium steel that is processed to deliver superior
strength and fatigue properties. L19 is a very high strength material
compared to 8740 and ARP®2000 and is capable of delivering clamp
loads in the 230,000-260,000 psi range. It is primarily used in short track
and drag racing applications where inertia loads exceed the clamping
capability of ARP®2000. Like most high strength, quench and temper
steels—L19 requires special care during manufacturing to avoid hydrogen
embrittlement. This material is easily contaminated and subject to stress
corrosion. It must be kept well-oiled and not exposed to moisture.
MATERIALS USED IN THE MANUFACTURE OF CAP SCREW TYPE CONNECTING ROD BOLTS

INCONEL 718: A nickel based material that is in the high temperature,
super-alloy class, it is found to be equally suitable in lower temperature
applications. This material delivers tensile strengths into the 220,000 psi
range and exhibits improved fatigue properties. Best of all, Inconel 718
is completely immune to hydrogen embrittlement and corrosion.

ARP3.5 (AMS5844): While similar to Inconel 718, these super-alloys
are found in many jet engine and aerospace applications where heat and
stress attack the life of critical components. The high cobalt content of
this alloy, while expensive, delivers a material with superior fatigue
characteristics and typically tensile strength in the 270,000 psi range.
The immunity to hydrogen embrittlement and corrosion of these materials
is a significant design consideration. These materials are primarily used in
connecting rods where extremely high loads, high RPM and endurance
are important factors—Formula 1, Winston Cup and CART applications.

CUSTOM AGE 625 PLUS®: This newly formulated super-alloy
demonstrates superior fatigue cycle life, tensile strength and toughness—
with complete resistance to atmospheric corrosion and oxidation. ARP®
is the first to develop manufacturing and testing processes for fasteners
with Custom Age 625+. Best of all it is less expensive and expected to
soon replace MP-35 as the material of choice in the high strength, super-alloy
field. Typical tensile strength is 260,000 psi.

BTW, ARP will custom make rod bolts for you in any material they have available, however you will pay for it. Drew