Any changes in 996 engine, 1999 vs later years?

[baloo]

Just bought a 99 - 996 which had engine replaced (2006) courtesy of Porsche. Would like to know if a 2006 engine (or later years 996) might have resulted in any improvements in reliability, hp, etc.

Also, does anyone know where i can check block casting numbers to find out what year this "new" engine might actually be?

Thanks.

[racer]

I think the remanufacturered motors have a different ID number/sequence (at least I recall that from a Boxster engine discussion.) HP change? no. Reliability? perhaps.

[paspar2]

Your replacement engine is almost surly a 3.4l just like the original was. In 2002 the 996 got a face lift and a bump in displacement to 3.6l producing 320hp (up from 300 for the 3.4)

[EBS_Don]

The biggest difference would be the updated intermediate shaft with the larger single row bearing. I've seen this update/upgrade even on replacement engines for 2.5 Boxsters. Otherwise, no notable changes.

[baloo]

Originally Posted by EBS_Don

The biggest difference would be the updated intermediate shaft with the larger single row bearing. I've seen this update/upgrade even on replacement engines for 2.5 Boxsters. Otherwise, no notable changes.

Thanks. I had been reading about aftermarket crankshaft bearing improvements, and was wondering if they ever made that correction on the 3.4. Now, when you say "intermediate shaft" you are referring to a bearing midway on the crankshaft, right (i.e., not one of the end bearings)?

[Rrrockhound]

Originally Posted by baloo

Thanks. I had been reading about aftermarket crankshaft bearing improvements, and was wondering if they ever made that correction on the 3.4. Now, when you say "intermediate shaft" you are referring to a bearing midway on the crankshaft, right (i.e., not one of the end bearings)?

The intermediate shaft runs the length of the block. It spins the cams and it's chain-driven by the crankshaft.

[baloo]

Originally Posted by Rrrockhound

The intermediate shaft runs the length of the block. It spins the cams and it's chain-driven by the crankshaft.

Thanks for the info. I think it's time I updated my knowledge about the P water-cooled engine and looked at an exploded diagram of the internals. Seems like an extra shaft in the process would increase the friction, and therefore rob energy -- but I'm sure a couple of engineers at Porsche musta thought of that beforehand.