Last(?) IMS thread for the year

[Homeoboxter]

Happy New Year to Everyone!

So, here`s the potential last IMS question for the year: does anyone know the number of the non-serviceable IMS bearing? I just traded this 3.2 S engine basket case and surprisingly it came with this kind of IMS (bearing is missing). I thought this IMS appeared in the newer 3-chain engines, but this is a 5-chain, probably a transitional version, from 2004 I believe:

[911monty]

2005 3.2 M96 for Boxster S was the transitional year for the large non serviceable IMSB.

https://lnengineering.com/products/the-definitive-guide-and-faq-for-porsche-ims-bearings/my06-08-porsche-cayman-boxster-911-ims-bearing.html?limit=8&mode=list

[Homeoboxter]

Yes, I came across that too, based on that info the engine should be 2005 or newer. Now, looking at the Bentley manual, looks like the 3-chain engine with the redesigned variocam came out in 2003, but this engine is definitely a 5-chain. It`s possible that this IMS is not its original. Or perhaps this was a factory replacement engine which Porsche built after 2005 with the newer IMS but with the early variocam system to match the DME

[JFP in PA]

Originally Posted by Homeoboxter

Yes, I came across that too, based on that info the engine should be 2005 or newer. Now, looking at the Bentley manual, looks like the 3-chain engine with the redesigned variocam came out in 2003, but this engine is definitely a 5-chain. It`s possible that this IMS is not its original. Or perhaps this was a factory replacement engine which Porsche built after 2005 with the newer IMS but with the early variocam system to match the DME

Once Porsche moved to the oversized third generation IMS bearing, factory reman five chain engines used the oversized bearings. If this was a factory reman, the engine numbers on the oil sump rail would indicate it is a retread.

[Homeoboxter]

Originally Posted by JFP in PA

Once Porsche moved to the oversized third generation IMS bearing, factory reman five chain engines used the oversized bearings. If this was a factory reman, the engine numbers on the oil sump rail would indicate it is a retread.

Yes, that`s exactly the case. Engine number has "AT" in it. Mystery solved