So this will be interesting or not...

[speedo]

I have a rogue set of 84mm high compression pistons that I was told long ago were Cosworth. I just posted these for sale and after looking at the pics of the inside of the dome find the name "Hepolite" instead of Cosworth. I google Hepolite and find it is a British company that makes pistons for motorcycles. I try several different searches and see no mention of Hepolite making racing pistons for cars. I am very curious from the depth of knowledge on this board, (as a number of the members are also addicted to early motorcycles) what they can tell me about these pistons.

Speedo

[Chuck Miller]

Speedo,

I remember Hepolite was the 'next step up' size wise option back in the day when you wanted to make a '1600' twin cam Ford a little bigger then the actual (I think) 1558cc's.

The company has been around for a long time....

[chris_seven]

Hepolite was the brand name of a company called Hepworth and Grandage who merged with Wellworthy Pistons in 1989 to form AE Piston Products.

You can see the AE logo inside your piston.

I believe AE are now part of Federal Mogul.

The Heoplite Brand name has recently been purchased by Wassell Ltd and they market a range of pistons manufactured in Taiwan.

Back in the Sixties Heoplite were the pistons of choice for the majority of Race and rally car engines and for the majority of British Racing Motorcycles.

Heoplite introduced a brand known as Powermax forged pistons and dominated the UK market.

It all started to fall apart after the formation of AE and eventually the competition range of pistons was abandoned and the market taken by companies such as Omega (Started in 1972 by, I believe an ex-Heoplite Engineer)

Cosworth would almost certainly have used Hepolite Pistons in the early days of race Engine Building and when they started to market products branded as Cosworth it would not be surprising that they were manufactured by AE.

Hepolite Powermax Pistons were forged from alloys not unlike 4032-T6 which is typical of the alloy used by Mahle for the 911S pistons.

Cosworth branded pistons are still available although now I think they are more likely to be made by CP - but I am not 100% sure.

IMHO if these pistons are still in good condition they should be equally as good as Mahle pistons.

[Fritz A. Ficke]

Great information Chris, Thanks.

[speedo]

Chris,
Thanks. Where would I go to try to find a 6th piston to make a set? AE, Cosworth? Maybe an old school race shop?

Speedo