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YOUR RESEARCHx-51 engine not affected by IMS??
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Suspected cause · Original poster
I was looking at a 2004 C4S recently and the owner mentioned that "I don't believe IMS issue is applicable to my X51 engine anyway".
Outcome qualification: Negation, uncertainty or missing explicit repair resolution overrides the raw extraction signal.
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Outcome qualification: Negation, uncertainty or missing explicit repair resolution overrides the raw extraction signal.
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I was looking at a 2004 C4S recently and the owner mentioned that "I don't believe IMS issue is applicable to my X51 engine anyway". In a followup email, I again expressed concern with a low mileage car without retrofit, and his reply again was "I don't believe IMS affects the X51 engines".
I've searched the forums extensively and couldn't self-answer. I am not paranoid (cautious, yes) and hate to even bring this up, but isn't his answer horsefeathers? From my understanding, X-51 gave you different pistons, upgraded cams, modified cylinder heads, different inlet and exhaust manifolds, new programming, but didn't do anything about IMS retrofit. Am I crazy (or at least just bad at search)??
From my best understanding, X51's in the 996 are no different from an IMSB perspective.
The Turbo and GT3 have the Mezger motor (which does not have the highly reported IMSB issues of the C2/C4s) and this fact may be what seller is paraphrasing incorrectly.
I am certain someone will correct me if I am wrong.
2004 C4S with X51 motor does have IMS issues. It's the same engine as regular 2004 996 but has x51 kit. X51 is a better stronger version of the 3.6l with 345hp, kit camshafts, flow optimized cylinder head ports, increased engine speed, and other modifications
I have an 2004 996 AE car in the fleet. All AE cars came with X51.
My understanding is this small sample group of 1964 cars has a very low failure rate. Why? AE cars are Porsche enthusiast owned and therefore driven and maintained differently? Luck? Probably. X51 no relationship to IMS failure. Not an expert. Far from it. My humble take is drive it and enjoy it.
If mine goes I will ship it to JR and he will build me a monster 3.8L and will flog on the track! 25k later. Or, it will be a nice parts car for someone and I will move on to another P car. I simply understand the risk and enjoy the cars, flaws and all.
Why? Is an IMS retrofitted car a requirement?
I would prefer to buy a virgin car myself as you know what you're working with. IMS retrofitted cars could've been done in a reactive mode after it started shedding metal, not properly prequalified and thus waiting to manifest itself after retrofit, not properly installed, might be toward the end of their service interval, etc.
The short block of the X51 is the same as any M96.03 engine. I have had as many as 3 of these engines here at once with failed IMS Bearings. They fail just like any other M96.03
IMS is not required, but with what the ask was, it just didn't make economic sense to buy car and then do IMS. Sadly, I'm not at the point in life where money is no object.
The bearing makes perfect financial sense and provides peace of mind. Unfortunately these cars aren't cheap to run! I had 5k worth of bills in the first month clutch (which I knew when purchasing), LN IMSB and a water pump. Not much you can do about it!
^^^
In my experience as well. Maintenance costs can be high. I also spent about $5k in the 1st month of ownership for RMS, IMSB upgrade, clutch, flywheel.
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