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Discussion summary
YOUR RESEARCHAdvice on new engine for 99
Reported or suspected cause
connecting rod bearing
Reported cause
No successful repair reported for this finding.
1
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0
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0
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Reported cause · Original poster
VERY good mechanic was very sure it was the connecting rod bearing.
Leading evidence: 'connecting rod bearing' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'connecting rod bearing' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Replace 3.4' (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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Suggestion
Replacing your 3.4 with a 3.6 really isn't an option.
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Suggestion · Original poster
My question is, do you guys have any suggestions for replacing the engine?
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Suggestion
I put 30k miles on it including a bunch of DE and a year of club racing and it was still running like a top when I pulled it in favor of a 3.6L X51.
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4 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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So ... my 99's engine broke. The core is still good, and actually it still runs, but makes bad knocking noise, so other than to load on trailer, it hasn't been run. VERY good mechanic was very sure it was the connecting rod bearing.
There has been some excellent advice on this board, so I'm posting an open question to all.
My question is, do you guys have any suggestions for replacing the engine? ie, should I go with a new 3.4L crate motor direct from Porsche? I've heard this costs about 7K {complete except for A/C and flyweel}. How much typically to instal? What about 3.6L crate motor? Maybe rebuild of my broken engine and bore it out during the rebuild. Should I get a used 996 engine instead? Or maybe a used Cup Car motor?
I plan on tracking it a lot, almost exclusively, and I'm looking for the most reliable and long term cost effective solution.
Thanks in advance for your suggestions!
Pete,
The 3.4 replacement from Porsche is a no brainer. You will pay $6,800 to $7,000 plus your engine for a new or Porsche rebuilt 3.4. It does come complete and can be installed in a day by any competent shop. Total cost should be well under $8k.
Replacing your 3.4 with a 3.6 really isn't an option. I did it but on a track only car. You'll have e-gas issues, wiring harness issues, fuel system issues, vario cam issues, etc. If you do get it to work, plan on spending 2 to 3 times as much as a 3.4 replacement.
The cup car engine will cost you more than your car is worth and must be rebuilt at regular intervals. I don't recall how often but 30-50 hours sounds about right. Sounds like a fun option but I don't think its practical.
Rebuilding your engine may work but I would expect to pay around $15K. That's about what a 993 rebuild is. I could be wrong.
I'm sure you can get a used motor from one of the dismantlers but that seems to be a little scary. I looked into this when I was looking for a 3.6 but quickly decided the factory engine was the way to go.
If you are really brave, I will sell you the 3.4 I took out of my race car. It was a fantastic engine. I put 30k miles on it including a bunch of DE and a year of club racing and it was still running like a top when I pulled it in favor of a 3.6L X51. Obviously it would be priced to reflect it's somewhat checkered history.
Good luck.
Jim
Thanks JimB! I think that's exactly what I'll do.
One other question, think it makes sense to change the clutch or flywheel setup while the engine is out of the car?
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