Technical Video:


Part No: MED-1275-CR-618
Regular price £1,125.00 £937.50 EXC VAT
Regular price Sale price £1,125.00 £937.50 EXC VAT
Availability: In Stock

Technical Video:



The MED steel conrods are one of the lightest and strongest ever designed for the 1275 A-Series engine, weighing just 430g. Long 6-inch length for use with short height pistons.

Longer rods alter the basic geometry of the rotating assembly to improve performance. Running a shorter compression height piston then offsets the minimal weight gain of the longer conrod. 

Our 6-inch conrods only weigh 5g more than our 5.750" design!

Made in the UK, with genuine ARP bolts.

Conrod features

    • Double air re-melt steel
    • 18mm little end bush for Omega forged lightweight pistons
    • 1.625" Cooper S size big end journals
    • 6.000" length, for short height pistons
    • Fully machined
    • Uniform machine peening
    • Balanced end-to-end within a gram
    • 100% magnaflux tested
    • Laser-etched MED logo
    • Fitted with ARP fasteners

Please see the additional information tab for more detail and recommendations.

Supplied as an engine set of four.


Additional Information

Material spec
Our conrods are fully machined from double air re-melted 817M40 forgings. All rods are shot peened using an automated process to increase fatigue strength and durability. The rods are balanced end-over-end into matched engine sets and are 100% magnaflux crack detected prior to final inspection by CMM in a temperature controlled inspection department. As part of the design process, we worked closely with ARP to select the best available fasteners.

Piston compatibility
These conrods are 0.250" longer than standard, so you will need to run 1.248" compression height pistons to achieve the same deck clearance.

This set features a bushed little end to accept fully-floating gudgeon pins in the lightweight 18mm design. They are an ideal match for our competition-grade Omega forged pistons with 18mm pins.

Crankshaft compatibility
All MED conrods feature 1.625-inch big ends to suit 1275 Cooper S, MG Midget or MED steel billet crankshafts. We do not produce conrods for the larger diameter 1.750-inch big ends, as the extra weight here does not lend itself to full competition usage.

MED conrods vs standard
There's three benefits over standard conrods - strength, light weight and high quality. H-section steel conrods are considerably stronger than mass-produced standard conrods, which were never designed for high performance applications. Standard conrods can be lightened and balanced, but even then our steel conrods will be lighter and stronger. The highly accurate production process allows for exact build tolerances; you will not find a higher quality A-Series conrod.

Torque settings
These should be torqued to 30lb.ft, or preferably checked using an ARP rod bolt stretch gauge and stretched to 0.0050"-0.0055". You will need a 12-point 9mm socket/spanner.