Part No: MED-1293-IBC
Regular price £4,325.00 £3,604.17 EXC VAT
Regular price Sale price £4,325.00 £3,604.17 EXC VAT
Availability: In Stock


The MED inline crankshaft is CNC machined from EN40B steel billet and nitride hardened, with extra large C-shape counterbalance webs to reduce potentially damaging harmonics.

1275 Midget size big end journals with counter-bored webs reduce weight and further enhance the counterbalance effect. An improved counterbalance helps to reduce the 'whip' often encountered with the three main bearing A-Series crankshaft, to improve longevity and performance at higher RPM levels. 

This crankshaft kit is ideally suited to race series such as Appendix K historics where a more traditional stroke length and big end size must be retained. It would also suit high performance road, rally and trackday builds.

Crankshaft kit contents;

    • MED 81.33mm EN40B steel crankshaft

    • MED steel conrods 

    • Omega forged lightweight pistons

    • ACL Race main bearings

    • ACL Race big end bearings

    • ACL thrust washer set

Kit options;

    • 5.750" or 6.000" conrod length

    • 1.498" or 1.248" compression height pistons

    • +20, +40, +60 or 73.5mm piston diameter

    • Flat top or dished pistons

    • A-Series or A+ main bearings (Marina block)

Please select your chosen engine capacity from the dropdown menu, then a member of our sales team will be in contact to confirm your options after purchase.

Please note - the timing gear end has a carefully machined radius for extra strength - please be sure that your timing gear sprocket has a matching radius or damage will be caused on assembly.

If you're not restricted by race regulations, you may be interested in upgrading to the more radical MED Inline Multiweb crankshaft kit, which further improves the counterbalance effect.

Please see the additional information tab for frequently asked questions.



Additional Information

Why is an MED steel crankshaft better than a standard type?
Most factory crankshafts were made from lesser grade EN16T, as opposed to certified EN40B steel billet. The counterbalance effect is also far greater with this design, so it is both stronger and better balanced. 

An improved counterbalance effect helps to reduce the 'whip' often encountered with the three main bearing A-Series crankshaft, to improve longevity and performance at higher RPM levels. 

Whilst standard crankshafts can be effectively re-worked to improve their counterbalance effect, it is not possible to add material, only subtract. You're also unlikely to know the history of a second-hand crankshaft - it could be over 50 years old! 


Do I need to use steel main caps?
Ideally, yes. We would highly recommend an MED four-bolt steel main cap set, AFS studs and line-boring of the block when upgrading to a steel crankshaft. On a road car, an MED centre main strap kit may suffice, but it's not the ideal arrangement when using a such a high-end crankshaft.

Which conrods should I choose?
We can supply either standard length 5.750" steel conrods or longer 6.000" conrods. Longer rods alter the basic geometry of the rotating assembly to improve performance. If you'd like the longer rods, we can then supply short compression height pistons to retain the same deck clearance as standard. 

Some race series stipulate that you must use the standard conrod length. In this case we sometimes supply the same short height pistons and the block is machined down to suit. Please contact us if you're not certain.

Which pistons do I need?
The bore size may depend on your race regulations, the block you have to work with, or personal preference. We can supply a range of different compression heights and crown designs to create your desired compression ratio.

Can you make me a custom steel crankshaft?
Unfortunately with the design, drawing and machining costs involved in producing a custom design crankshaft, it would prove too expensive. However, we have developed our crankshaft designs over many years using decades of A-Series engine experience, so you can be assured of the best possible setup for the vast majority of applications.

What's better, billet or forged steel cranks?
This is an area of much debate. In use we have found no tangible difference in strength and reliability between the two manufacturing techniques. We prefer machining crankshafts from billet, as this allows for regular design development without needing to make a new forging tool each time, which would not be economically viable. 

Does this come with any certification?
Each crankshaft is supplied fully balanced with certification, 100% crack detection and certification of material and heat treatments. Critical detail inspection reports are also supplied.