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Hey matt, the pistons did have to machined to clear the oil squirters.... which should have already been done. Took extra time having to be machined and re-balanced. Know that they are in all my worries have gone. There is absolutely no piston slap when cold, my catch can has almost no oil since the first start-up and now I`ve travelled 2200km's. I did a compression test and found dead even across the lot. Only slight hick up was a oil leak which turned out to be coming from the half moon seal at the rear of the valve cover.

I removed the pistons with the block still in the car. Very easy for anyone wondering.

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9krpm - not sure about getting special prices on other OS pistons, but Matt got the pistons from a guy we found on Ebay. He'd bought them (they were still brand new in box) and then no longer needed to use them so sold them off.

Might just pay to check out a few of the performance part websites and see what prices everyone has to offer - we did that and they do vary a fair bit ;)

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9k, Yes the main reason I went for the OS pistons was from what I have learnt regarding piston expansion under temp. The pistons I bought were of the low silicon type (OS sell both types). I can't remember the exact number of grade. They were $2700 compared to $1800 for the lower grade. I can confirm they indeed have absolutely no piston slap when cold. As I said to Matt(whatshisname) they had to be modifed and then rebalanced to allow clearance for the oil squirters, glad I didn't pay full price.

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Been down to Unique Autosports. They have seen 330rwkw with the standard injectors and an Adjustable Fuel reg. Funny how people do things totally different from state to state. In SA I was told not to bother as anything over 260rwkw is not achievable with a fuel reg. Hopefully it will be tuned for Uniques next track day =) Yip Yar

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