Product successfully added to your shopping cart
Quantity
Total
There are 0 items in your cart. There is 1 item in your cart.
Total products
Total shipping To be determined
Total
1.6L 16v - B6
Manufacturers
1.6L 16v - B6
Warning: Last items in stock!
New product
Set of 4 forged 4340 steel connecting rods for the Mazda MX-5 1.6 & 1.8 (B6 / BP).
The Mazda B6 / BP is the family of 1.6 and 1.8-litre inline-four DOHC 16-valve engines that powers the Mazda MX-5 (Miata) NA and NB generations. The B6 (B6-ZE) displaces 1,597 cc (78 mm bore, 83.6 mm stroke), while the BP (BP-ZE) raises capacity to 1,839 cc (83 × 85 mm). Cast-iron block, aluminium head and belt-driven cams make it a simple, light and durable design that has become a benchmark for both naturally aspirated and turbo builds.
Introduced in 1989 on the MX-5 NA 1.6, the engine moved to 1.8 (BP) on the NA8 and NB up to 2005; it also appears in the Mazda 323 / Familia and, in turbocharged BP-T form, in the 323 GT-X. Tough as standard, it is nonetheless held back by its factory rods as soon as boost climbs or the engine is held at high rpm in competition. Switching to forged rods removes that limit and secures high-power builds.
Machined from high-strength 4340 alloy steel, these forged connecting rods replace the sintered-metal factory rods to strengthen the B6 / BP rotating assembly. Forged, machined and shot-peened, they deliver far greater fatigue strength and withstand high cylinder pressures with ease.
Designed for built engines — turbo BP-T as well as high-revving naturally aspirated units — they cope with rising rpm and extra torque. Supplied as a set of 4, balanced and with their ARP bolts, they are the foundation of a reliable short block, from intensive use to competition.
| Reference | Brand | Profile | Bolts | Pin diameter OEM 20 mm | Small-end width | Big-end diameter OEM 48 mm | Big-end width | Center-to-center OEM 132.8 mm | Weight per rod |
|---|---|---|---|---|---|---|---|---|---|
| R-MAZ-001-H | ZRP | H | ARP 2000-3/8"-38mm | 20 | 48 | 21.8 | 132.8 | 418 | |
| R-MAZ-001-H-L19 | ZRP | H | ARP L19-3/8"-38mm | 20 | 48 | 21.8 | 132.8 | 418 | |
| 14011-4 | Manley | H | ARP 2000-3/8"-38mm | 20 | 48 | 21.8 | 132.8 | 535 |
| Rod | Bolts | Torque | Recommended stretch |
|---|---|---|---|
| ZRP (R-MAZ-001-H) | ARP 2000-3/8"-38mm | 61 N·m | 0.140 – 0.152 mm |
| ZRP (R-MAZ-001-H-L19) | ARP L19-3/8"-38mm | 67.8 N·m | 0.152 – 0.165 mm |
| Manley (14011-4) | ARP 2000-3/8"-38mm | 81.3 N·m | 0.147 – 0.157 mm |
Manufacturers recommend the stretch method (with a gauge) over torque alone: it is the reference method for even preload on every bolt. The figures above assume the bolt and threads are oiled at assembly with ARP lubricant.
| 4340 steel is a nickel-chromium-molybdenum alloy steel prized for its outstanding balance of mechanical strength and toughness. Compared with the sintered metal of factory rods, it offers roughly 19% higher yield strength, about 8% greater tensile strength and 19 to 37% better fatigue strength — margins that mean a fatigue life several times longer under heavy loads. |
 | H-beam profile. The H-shaped section presents two wide flat faces that maximise bending stiffness for a contained weight. It is the profile of choice on high-torque, high-boost engines, where it stands out for strength and dimensional stability. |
The rod bolt is one of the most heavily stressed parts in the engine. The key is to match the ARP grade to the real use of the build, then to strictly follow the assembly torque and stretch.
 | ARP 2000. The most versatile high-performance bolt, with no storage constraints. In 3/8" it handles up to 200 hp per cylinder and 8,500 rpm: ideal for circuit, trackday, drift, rally, hillclimb and drag. |
 | ARP L19. Designed for engines pushed to the extreme — very high boost, sustained high rpm, high cylinder pressure. In 3/8" it allows up to 250 hp per cylinder and 10,000 rpm. Sensitive to corrosion and hydrogen embrittlement, it must be stored and fitted oiled. |
In addition to torque tightening, measuring bolt stretch confirms the actual preload: with the bolt fitted, place a dial indicator (stretch gauge) on its two ends and check that the reading matches the recommended stretch in the table above. It is the most reliable check of even clamping. |
 | ZRP (Drakos – Race Winning Brands): a well-known maker of forged 4340 steel connecting rods with a remarkable strength / value ratio. For the B6 / BP, ZRP rods come in H-beam with ARP 2000 or ARP L19 bolts. |
 | Manley Performance: a leading American name in racing engine parts. Its forged 4340 H-beam rod for the B6 / BP, fitted with ARP 2000 bolts, targets demanding builds seeking maximum rigidity. |
 | 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 |
These forged connecting rods are compatible with all vehicles fitted with the MAZDA B6 / BP engine, both naturally aspirated and turbo (BP-T):
| Brand | Model (chassis) | Engine code | Power | Years |
|---|---|---|---|---|
| Mazda | MX-5 NA | B6 | 115 hp | 1989–1997 |
| Mazda | MX-5 NA | BP | 128–133 hp | 1994–1997 |
| Mazda | MX-5 NB | B6 | 110–125 hp | 1998–2005 |
| Mazda | MX-5 NB | BP | 140–146 hp | 1998–2005 |
| Mazda | 323 / Familia GT-X | BP-T | 166 hp | 1989–1994 |
OEM reference: B6S7-11-210D (1.6 B6) and B6S7-11-210E (1.8 BP) — factory rod sold individually.
When a factory short block lets go — a broken or bent rod, spun bearings — the bill climbs fast, especially on a built engine. Refitting factory parts simply reproduces the same weakness.
For a comparable budget, even lower over time, fitting forged 4340 rods removes that weak link: the engine is made durably reliable and potential is freed up for tuning.
For the same budget: more reliability, more headroom, more longevity. It is the most cost-effective investment before raising the B6 / BP's power.
