Who modyfies 5 cylinder crankshafts for motorsport ?

[A80Avant]

to balance it you will need to have flywheel and rods?

[Albert]

I would say front pulley and the flywheel

[garym]

cranks

if you are looking for big power i would suggest a racing crank,arrows are very dear ,i would use doug kiddy crankshafts again not cheap buy it does all you will need ,the other is farndon cranks but theirs tend to be on the heavy side ,good luck

[Alistair E]

NCTS but I found this. Not lightened, but may be a starting point.

http://cgi.ebay.co.uk/Kurbelwelle-Au...742.m153.l1262

Alistair

[macspring]

Garym

Thanks, that's who I was trying to think of.

http://www.farndon.com

No connection to this company either.

Kind regards.

[terrybullwon]

Might be a issue


Cylinders 2,4,6,8,10,12 or 16
Plane Single / Multi Straight, Flat or Vee
Max. Length 1,000mm
Materials To Suit Application
Manufacture
Billet Any type of Crankshaft, Heat Treated to Raise Core Strength
Forged Farndon's own EN19 Lotus Twin Cam, Customer's Own or Special Order
Cast Customer's Own or Special Order
Finish Nitrided to Depth Required
Balance Fully Balanced Ready For Inspection
Inspection Full Metrology Service
Marking Engraved to Identify Origin

[repo]

For proper balancing You need to match the bobweights to the rods and pistons. I am not 100% sure reducing wight from counterweights is a good idea, when the h-beam rods usually are significantly heavier than original ones.

Like said, not sure. Never used knife edged cranks myself.

[Rusty]

When I asked about rod weight here I was told that H beam are lighter than OE

[mcandmar]

I know my SPM rods were lighter, stock ABY with bolts was 660g, and the SPM was 515g. Philip at BDB talked me out of knife edged cranks as my application is strictly for road use, he didnt feel there was anything to gain unless building a high rpm motor for competition use.

[quattro84]

You'll need to adjust the weight of the front torsional damper. It's inertia eliminates the angle of twist (= torsional stiffness) in the crank caused by the torsional moment between flywheel and harmonic damper.
Reducing weight means a change in inertia of the crank itself. And aftermarket rods/pistons give a difference in reciprocating mass.
Harmonic dampening is f***ed up matter to calculate/simulate. I am trying to solve it to get an idea of a possible enlightment of the front pulley for IL5 engines.