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YOUR RESEARCH996 catastrophic failure and rebuild saga
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Use motor has as a tremendous amount of risk
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Leading evidence: 'Use motor has as a tremendous amount of risk' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'crank) we passed' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check postings regarding problem areas' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suspected cause · Original poster
I looked at a few craigslist options, but for various reasons (like suspect crank) we passed on them.
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Suggestion
I'll periodically check your postings regarding problem areas that arise.
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Suggestion
While physically the engine may fall right in, I have yet to read a real review/road test of a 996 that has had this done.
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So I'm not sure just how valuable my saga could be to others on this forum, but since I've received SO much valuable information here I feel I should share and offer to discuss my project.
I bought a 2003 996 in Jan 2016. It was in beautiful shape and even had records from the last 2 owners (including LN IMSB, clutch & flywheel). I have had a few sporty cars in the past but this car is in a different league. I was hooked. My local PCA club is also full of awesome folks & I decided to HPDE the car. What a blast... till last run of the day...
Pulling hard on the front straight of HPR in 3rd gear maybe 5k RPMS and thinking I will need to be braking soon for turn 1 and I get a funny shudder as power flatlines for a second then the car dies. I drift off the track and am towed in. I meet a tech who does a quick check plugging his computer in (no unusual events), and we discover we cannot even pull the dipstick more than about an inch. When the pan is dropped - piston & rod chunks in the pan and you can see into places of the engine that you shouldn't be able to see. It's a catastrophic failure.
First decision: do I keep the car and rebuild it (and can I even afford to do this)?
Second decision: what path should I take on rebuild?
I will post more on the saga after I get some work done if there is interest, but as the story stands today, my rebuild with LNE 4.0 fired Friday, and is already showing decent numbers on the dyno without even stressing it (still early into break-in).
Good guess! We're guessing rod bolt failure too. Not worth my $ to tear into the old block to be sure since we know 100% it was catastrophic. May pull the heads since that's pretty easy.
oil pressure and temps were fine at time of failure.
no type 2 overrev events lifetime of the car, not many type 1
You have basically 3 options. You can buy your car all day, with with low mileage for $25-30k. Dont be sentimental, you dont have a collector car. These cars are completely fungible.
So option 1 is sell it as a roller for $3-7k usethe money to buy another. This is my recommendation.
Option 2, get a used motor. It's a crap shoot but you might find one for what? 7-10K but no guarantee . I wouldnt take the chance.
The last option is to buy a Porsche crate motor or a Raby rebuild for $20k plus. So now you have a car that you bought for X amount and add $20K plus to that amount. You will never come close recovering your investment.
Sell it as a roller and buy another one. If you take your time you can find a minimally modified 966 that is prepped for the track in the $20-30k range that won't blow up.
Pics are a bit of a problem since I didn't do the work myself and was present for VERY little of it. The few I have include mechanics whose permission to post I do not have.
I agree essentially with your advice. It's easy enough to find a nice 996 in the high teen or low twenties. It's silly to get attached to a car that is never going to be collectible (esp when not original engine).
Used motor has as a tremendous amount of risk. Totally unknown history on the car, can't do a PPI, often unknown mileage, etc. I was seeing $9k to $13K on a working pull from LA dismantlers.
I essentially chose the 3rd option. I know the overall condition of my car (very good overall), I know some of the history of my car, and if I scrap it and buy another 996 I could wind up with *exactly* the same issues because I'm buying so many unknowns (not sure if a more thorough PPI would have made a bit of a difference in my case). I chose to find a used but rebuildable long block (no easy task) and have it built from the ground up by someone who does this professionally and has done it more than a few times. This is *NOT* a cheap or a fast option. The only other real option I considered was an RND crate motor for about $20K - *but* all stock internals. I elected to go JE pistons, Carrillo rods, ARP bolts, IMS Solution, and much more to attempt to address all the possible areas of (future) failure if possible. Again, this is *NOT* a cheap or quick solution. Coming to grips with the cost and figuring out how to make all the funds come together took about as long as the build has, and it is certainly not a financially sound "investment". In the end I'll have a 996 with $50K or so invested that's maybe worth $30.
Could have been timing chain failure too. It doesn't sound like your car was revved high frequently.
Be very curious to see the state of the LN IMS, even though any observations would be tinged due to metallic debris being through the engine during meltdown
Ha! The donor engine! Posted by the providing donor himself!
I guess this is as good a time as any to talk about the donor engine. I needed a long block... heads, crank & cradle, IMS shaft, etc... since mine was toast. The hard part was finding an affordable option. Pulls were ranging $9k & up. I was really hoping to find one for under $6K since I knew the build was going to be expensive.
I looked at a few craigslist options, but for various reasons (like suspect crank) we passed on them. Finally a Rennlister (yep, Byprodriver) answered a frustration post I made with a possible donor engine at a really reasonable price. He admitted he wasn't sure of its condition but was pretty certain it would work for my needs. I bought it sight unseen and he shipped it freight.
I was present for the tear down and we were mostly really pleased. Heads were in good shape with no indication of piston to valve contact. Crank looked really good tho bearings were pretty worn. One of the chains had apparently snapped and when this occurred it damaged teeth on the IMS gear. This was the only unbudgeted internal part I had to replace. LN replaced it for a fair price when I had the IMS solution done. Overall, I wound up with an excellent donor motor at a really decent price - thanks, Bill! I really appreciate it.
Pics are the donor long block & tear-down to the cradle.
Could have been a chain I guess. My tech's best guess is rod bolt though.
Replacement LNE upgraded IMS bearing had less than 20K miles on it at the time of engine failure. I seriously doubt it was a contributing factor.
Yet another set of opinions:
Don't put in another 996 engine, what with the known IMSB problems (even with the fixes!).
Good advice above -- if you really love the 996, then get another one that is running. It just ain't a classic, and it ain't worth the price of one or two used running 996's (by the time you REALLY get it sorted out).
Other option, put in an LS Vette engine and be done with the Porsche arrogance and elitism that lacks dependability.
This LS engine swap gets tossed out like it is a drop in replacement.
While physically the engine may fall right in, I have yet to read a real review/road test of a 996 that has had this done.
One has to wonder how beyond the engine fitting how the car as a whole works? I don't think the presence of the V8 with its OHV configuration upsets the balance of the car that much. (The 6.0l V8 in my 2006 GTO was a rather small engine given the tiny valve covers and the weight is down low in the engine.)
I'm more concerned about precise engine control, good emissions, proper engine and engine compartment cooling, and access to the plugs and coils and such on the LS engine. What about the A/C, power steering and brakes?
A whole lot of things have to work right before this engine swap makes any sense.
The first time you take your new 4.0 and run it up through the gears, all of the above bull crap will disappear from your mind and you will become one with your 996, again, and everyone else can just STFU.
Yup... that was my reasoning. I wasn't convinced that in the long run it would be better and significantly more cost effective. It helps that I have a mechanic nearby that has done quite a few 996 complete rebuilds with LN kits, and has built cars for race teams... he has considerable experience.
The price on the long block was very good, and I spoke with Bill (the offeror) on the phone and communicated via email. My gut said it was a good deal and was about perfect for what we needed, and that he was being honest with me. Fortunately I was right.
To the OP sorry to hear about your engine, awesome that you're back on track!
Lots of "the 996 isn't classic" blah blah blah, I don't care for talk like that and all is does is bring negativity
</rant>
Its great you're rebuilding, keep us posted!
So I figured out how to upload the video of a few seconds on the dyno shortly after first fire:
You Tube
My 2003 C4 Cab with rebuilt engine
LNE 4.0 upgrade
Carrillo rods & ARP bolts
Headwork by Hoffman
IMS solution
FabSpeed X-pipe with high flow cats
other little things to give it an overall complete refresh
Hopefully will have dyno numbers soon, but so far seems to be running well.
Having the benefit of emotional distance from the 996 and its problems and worries, and having ALSO spent an inordinate sum on TRYING to believe in that car, I can only offer a dose of bystander reality, which is negative.
It will be interesting to see how things go with you over the next, say, two years.
I agree with the prior post that an LS conversion is probably fraught with unforeseen problems -- AND, I have no experience with such a conversion.
However, for those of us who learned negativity in re. to the 996 through hard-learned experience, the LS seems to offer a glimmer of more reliability, more HP, much cheaper and plentiful parts (no Porsche tax), and even the promise of greater reliability (I know of no fatal flaws, like the IMSB, which is reportedly only good for 60K miles, whaaaaa???!!!).
Onward! Good luck. And keep posting. I'll periodically check your postings regarding problem areas that arise.
Hopefully, you will not have a "negative" epiphany like so many other owners who have been silent, or who dropped from posting here as they moved on to other models or marques.
I am aware it is a 14 year old car and it'll probably have more problems. Hopefully none will be as bad as catastrophic engine failure. I can tell you've not had a good experience with the 996. So far my experience is at both ends of the spectrum... both awesome & awful. Had I known I was going to have to invest so much in a rebuilt engine, I probably never would have bought the car. At this point I'm really hoping the awful experiences are behind me.
I suppose you have a point - most folks that give up on these cars probably don't post here anymore.
Seems my post didn't take...
Picked it up last night. It's still in break-in, but I can tell I've got much more torque. Once it's broken in, I should have dyno numbers. For any considering this route, know it's NOT cheap nor easy. I couldn't have done it myself, and it cost more that I thought... once you get into things on a 14 year old car, you'll find other stuff that needs to be taken care of beyond just your engine.
Glad to finally have it back.
That thing looked pissed on the dyno from your vid! Hard part's done and now it's time for miles of smiles. Congrats on getting her back in the canyons.
