Cosworth YB Pistons - Which are best and why?

[Cossie_Phil]

Hi Guys,

Im interested to hear everyone's opinion on Cossie pistons. Which brand is best and why?

There are quite a few available like Mahle, Cosworth, Wossner, CP Pistons to name a few.

Which are the lightest/strongest/etc?

Which are best for big power...eg 500hp plus?

What limits are known for different brands/specs?

Cheers,

Phil

[Clint]

Mahle are the best all round, lots of the original touring cars all used them they are very strong. £400 a set from ebay

For ultimate strengh has to be Cosworth Racing Group A Pistons, these are very DET resistant. £700 a set direct from cosworth.

While these are still available I woudnt use any other piston.

[Cossie_Phil]

Thats great feedback Clint I want to spec my new engine up to be able to mechanically handle 600hp. Do you think the Mahle's would be upto it if the rest of the package can deliver?

Any experience with CP Pistons? Does anyone in the UK use them? They have an exceptional reputation in Australia, just curious to hear from someone that has actually used them and stretched their limits in a Cossie engine.

[Slymanrs2]

I am using Cosworth forged GrpA pistons in my engine build as they are the most accurate and have proven to be very strong.
£680 is at the high end for 4 pistons, but for an engine component that takes the brunt of abuse and boost/heat then its a very important purchase.
If possible I would get the pistons before a rebore/hone to allow the best tolerance gaps.

See here for my build-

http://www.oldskoolford.co.uk/phpBB2...5150&highlight=

[Alg1k]

Im using the cosworth pistons in my YB i run a gt35 at 2.7 bar
I have just had to strip the engine as i have spun a bearing on track,
The pistons have been in the engine for 5 years they have had a lot of abuse over the years Lots of track days santa pod and running to work
I also use 150 shot of nitrous
The pistons have come out of the engine absolutly mint
I am going to re ring them and use again
These pistons have done...wait for it ....
27.000 miles
The only thing i did with them before fitting is
I had them ceramic coated and dry slided
I also changed the oil every 3000 miles
I would not use any other piston now,

[Cossie_Phil]

Cheers Guys

The decision is made...I will place an order with Cosworth