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Reduced price! TOYOTA référence R-TOY-003H Kit 4 bielles forgées en H ZRP avec vis ARP View larger

Forged connecting rods Toyota 4A-GE 1.6 16v & 20v (Corolla AE86) 18 mm pin for forged pistons

New product

Set of 4 forged 4340 steel connecting rods for the Toyota 4A-GE 1.6 16v & 20v, 18 mm pin.

  • ZRP brand (H profile)
  • Fits Corolla AE86, MR2 AW11, Celica, Carina
  • Engine codes 4A-GE (16v & 20v)
  • ARP 2000 or L19 bolts (3/8")

More details

476,86 € tax incl.

-26%

644,40 € tax incl.

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  • The Toyota 4A-GE engine

    Introduced in 1983, the 4A-GE is the sporting member of Toyota's A family: a 1.6-litre (1587 cc) inline-four with twin overhead camshafts and 16 valves, taken to 20 valves on the later generations, with an 81 mm bore and a 77 mm stroke. A naturally aspirated block famed for its eagerness and love of high revs, it was built until 2002 and went through several evolutions, from the early "big port" to the 20V Silvertop and Blacktop versions with variable valve timing. It powered a long line of Toyota models: Corolla AE86, MR2 AW11, Celica, Carina, Corona and Sprinter.

    The 4A-GE owes much of its legend to the Corolla AE86, a light rear-wheel-drive car that became an icon of drift and Japanese car culture. That aura made it one of the most tuned blocks in the world: individual throttle bodies (ITB), aggressive camshafts, raised compression and rpm beyond 8,000, with some builds even converting to forced induction. But as soon as engine speed and load climb well past factory values, the stock rods become the weak link of the reciprocating assembly. Replacing them with forged rods is the decisive step to reliably secure a high-revving or heavily built 4A-GE.

    The forged connecting rods

    Our forged 4A-GE rods are machined from wrought 4340 steel, the reference alloy in motorsport. They suit every discipline: circuit, drift, rally, drag, time attack and hillclimb, and support a high-revving naturally aspirated 4A-GE as well as a heavily built engine. Depending on the target (Stage 1 reliability, Stage 2 tuning, Stage 3 high power and beyond), they lock in the power increase without ever cutting corners on reliability. Supplied as a weight-matched set of 4, they keep the 4A-GE's 18 mm piston pin and 122 mm center-to-center length.

    Compared with a cost-driven sintered factory rod, a forged 4340 rod delivers about +19% yield strength, +8% tensile strength and +19 to +37% fatigue endurance. That mechanical reserve lets a 4A-GE pushed in rpm absorb cylinder-pressure peaks and the inertia loads typical of high engine speeds without breakage. The entire range is made from this forged 4340 steel, proven on the most demanding builds.

    Technical specifications of the 4A-GE forged rods (18 mm pin, 122 mm center-to-center)

    ReferenceBrandProfileRod boltsØ pin (mm)Small-end width (mm)Ø big end (mm)Big-end width (mm)Center-to-center (mm)Weight (g)
    R-TOY-003HZRPHARP 2000-3/8"-38mm184321,85122441
    R-TOY-003H-L19ZRPHARP L19-3/8"-38mm184321,85122441

    Tightening torque and stretch

    Torque and stretch depend on the chosen bolt reference; refer to the datasheet supplied with the kit. Checking stretch with a gauge remains the most reliable and repeatable method to guarantee preload.

    ReferenceBrandRod boltsMax torque (no gauge)Stretch (gauge check)
    R-TOY-003HZRPARP 2000-3/8"-38mm610,140 à 0,152
    R-TOY-003H-L19ZRPARP L19-3/8"-38mm67,80,152 à 0,165

    Technical guide

    Forged 4340 steel: what is it?

    4340 is a low-alloy steel with nickel, chromium and molybdenum. Forging aligns the metal fibres in the direction of load, closes internal porosity and delivers far greater mechanical strength than a factory sintered or cast rod. The result is a tensile strength of around 930 to 1080 MPa together with high fatigue endurance, essential as soon as the engine gains torque, power or revs. This is the material used across our entire 4A-GE range.

    The rod profile

    H-BeamThe H profile (ZRP), recognisable by its two flat flanks, delivers high bending stiffness for a controlled weight. Machined from 4340 steel, it is a robust and versatile choice, well suited to the 18 mm pin 4A-GE, available with ARP 2000 or L19 bolts.

    How to choose your rod bolts? ARP

    ARP 2000ARP 2000: the all-round benchmark alloy, with a tensile strength of about 220,000 psi (1,517 MPa). Offered here in 3/8" diameter, it covers the vast majority of 4A-GE builds, up to about 200 hp per cylinder and speeds reaching 8,500 rpm. It is the default choice to make a sporting 4A-GE reliable.
    ARP L19ARP L19: a very-high-strength, stiffer steel intended for the most heavily stressed 4A-GE engines, up to about 250 hp per cylinder and the highest engine speeds. In 3/8" diameter it clearly widens the safety margin on hard builds (note: corrosion-sensitive, it requires careful storage).

    Measuring bolt stretch

    On a forged rod, the exact bolt preload is checked by its stretch, measured with a dial gauge (stretch gauge), rather than by torque alone: lubrication and run-in distort the torque reading. Always refer to the stretch values given by the bolt manufacturer.

    View the ARP stretch gauge

    The brand offered

    ZRPZRP is a Greek brand of high-performance forged connecting rods, designed by Alex Drakos in Athens. Each rod is forged from 4340 steel, precision-machined and balanced to ±1 g to stay reliable at high rpm. On this 4A-GE range it is offered in an H profile with ARP 2000 or L19 hardware. Designed and inspected in Greece, these rods are proven in rally, on track and in drift, at the best price-to-performance ratio.

    Glossary

    1) Small end
    2) Small-end diameter
    3) Rod beam
    4) Rod bolt
    5) Big end
    6) Rod nut / bolt
    7) Rod cap
    8) Big-end diameter
    9) Center-to-center

    Vehicle compatibility for the Toyota 4A-GE engine

    These forged rods fit the Toyota models powered by the 1.6 L 16v (and 20v) 4A-GE inline-four, with a 18 mm pin and 122 mm center-to-center:

    BrandModel (chassis)Engine codePowerYears
    ToyotaCorolla (AE86)4A-GE124 ch1983–1987
    ToyotaCorolla (AE92)4A-GE116–125 ch1987–1994
    ToyotaCorolla / Levin (AE101)4A-GE (20V)156–160 ch1991–1998
    ToyotaCorolla / Levin (AE111)4A-GE (20V)165 ch1995–2000
    ToyotaSprinter / Trueno (AE82 / AE86)4A-GE124 ch1983–1987
    ToyotaCelica (AA63 / ST162)4A-GE124–125 ch1983–1989
    ToyotaCarina (AT171)4A-GE120–140 ch1988–1992
    ToyotaCarina GT (AT210)4A-GE (20V)165 ch1996–2001
    ToyotaCorona Coupé (AT160)4A-GE131 ch1985–1987
    ToyotaMR2 (AW11)4A-GE116–131 ch1984–1990
    GeoPrizm 1.6 GSI4A-GE132 ch1989–1992

    Why is it the most economical solution?

    On a tuned 4A-GE, a stock rod that lets go usually takes the block, crankshaft and pistons with it. Investing in a forged rod set from the outset costs far less than an engine failure followed by a full rebuild. You permanently strengthen the bottom end, preserve the value of your build and drive with peace of mind, in intensive use as much as day to day.