Need to choose between 2 used 3.4 for my C4

[danothemano]

Hi, I am new here but have owned 4 911's and a 912 in the past. I have purchased a 1999 996 Coupe with intermix from a cracked head or cylinder and ended up with 2 used 3.4 engines and need to choose one. Long story short, the first one slipped away from me and then was offered back after I had bought the second. I liked the price and took it, so now I have 2 used 3.4's.

I am doing the lne ims, rms, aos, water pump and anything else I see on the one I choose and will sell the other to recoup my cash. The original engine in the car with the crack has been sold.

The first engine came from the east coast and I was told it had 28k from a wreck. Model year is 2000 and I have NO way to verify miles that I know of, unless the engine # can yield info.

The second engine came from the west coast and has verified 72k from a 2001.

Any ideas you have that might help in determining which one to use and which to sell are much appreciated.

Edited March 27, 2011 by danothemano

[BReyes]

I would service/run the 01. Any compression numbers on each?

Regards,

[logray]

EDIT: LOL, I see this post was from March, I guess I'm not awake yet. Time for some more coffee. :beer:

....

Engine S/N doesn't yield mileage. However, if you post the serial numbers of the two engines we can validate the years and serial number for you.

Have you cold leak down tested each engine? That might be a good place to start...

I agree to stay away from wrecks.

Also the low miles on the 2000 doesn't sound good, from reading generally these engines seem to last longer and have fewer issues if they are driven regularly and hard.

That being said, if the 2001 requires a bottom and top end rebuild, the 2000 with retrofitted LNE bearing/etc. might give you more mileage before major rebuilds than you would get on the 2001.

It's a tough call for sure!

Also I am currently standing in the face of a rebuild myself, for low compression and lost ring seal. I might be interested in whichever engine you decide not to use as an option versus rebuilding what I've got.

Edited September 15, 2011 by logray

[phillipj]

Also I am currently standing in the face of a rebuild myself, for low compression and lost ring seal. I might be interested in whichever engine you decide not to use as an option versus rebuilding what I've got.

What? What ahppened?:unsure:

[logray]

Hey Phillip.

Reply is over in the valve job thread...

[danothemano]

Went with the 2000 low miles engine from the east coast. Just decided to roll the dice on this one and did NOTHING to it, except an oil change. Now have 5k on it after running the crap out of it this summer and have had zero issues. I have begun to believe that problems with this engine are luck-of-the-draw. All of this stated, this vintage 996 is extremely affordable and if they have a failure you just have to not go crazy on your remedy. I heard of a guy putting a dealer engine in his '99 for $20k. And he could probably get 18k for the car.