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4K Lightened Flywheel

Featured Replies

Hey guys

 

I'm looking for a lightened flywheel for our track car. By this I mean an original lightened unit, not a standard one that has been machined down.

 

Does anyone know where I can buy one?

What sort of weight are you looking for?

any reason you do not want to use a lightened cast iron original type? when machined properly with nice polished radii there is no issues. I have got one to under 5kg without much effort and the engine reved to over 9000rpm. I still have both my feet.

Edited by filfrederick

  • Author

Around 3-5 kilos I'd say.

 

Its comforting to know you didnt have a problem, though that is exactly what I am worried about. I have seen one let go along time ago and never forgotten lol!

 

On another note, can you share some info about your engine? 9000rpm must have had a big cam and great bottom end balance. What power at *rpm?

 

Cheers

Back in the day when there was no availibility of off the shelf stuff, everyone had there cast iron flywheels machined down.

 

Take it to a reputable engine shop and you will be fine. They will know where and how much to machine.

The rule of thumb for flywheels that I have always worked to it to keep it 10mm thick everywhere, all internal radii no smaller than 4mm and polished with 120grit after machining so that there is no grooves or lines that can be felt with the corner of a steel rule. the density of cast iron does vary slightly so balance will need to be checked after machining.

 

as for the engine, it was a while ago now. and as far as I know the current owner melted a piston with a bad tune and is still in pieces. Don't know a power figure as all tuning was done with a wideband and a data-logger on the road. It did sound good though.

 

http://www.rollaclub.com/board/topic/51097-4k-twin-cam/

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