I might have a lead on a wrecked donor car with LS1 and T56, but it has 150k miles on the car before the wreck (rollover). Is that too much to bother with?

The price is really good, and I am nowhere near ready to start the actual swap, so I could spend plenty of time tidying up the engine and stuff, though I have no experience rebuilding engines or transmissions.

I am pretty new to GM engines, but I've always heard they're really durable but what is the limit?

 

I would expect a hone and re-ring. The T56 seems a lot more based on abuse rather than mileage. You could probably run it as is, and deal with any issues as they arise, if you don't mind. Obviously the engine was running when wrecked. I think $2000-$2500 would be my price for that. I paid $2800 for my 80,000 mile drop out, which included wiring harness, ECU, accessories, etc. That seems cheaper than the norm, though.

 

Thanks.
This car is listed for $3k, but I could likely get it for less as it's winter and it has been listed for a few weeks.

 

As long as it's not a 98.

 

It is not. What is wrong with the 98s?

 

One-year only heads that have funky valve covers and flow like garbage
One year only PCM and harness that tends to self destruct randomly and brick itself and lacks the features/power of the later pcms
98s were also known for randomly snapping rods

It's pretty much a bastard year for the ls1 (and the 97 corvette ls1s).

 

Interesting. Good info, and I guess it just follows the general rule of "don't buy the first model year of anything" right?

 

If you can do a compression test, it might show if you should look further at the car.
The problem with the 6 speed Z28 or TransAm is that the performance crowd is heavier into them than the automatic and a whole bunch of them got thrashed heavily.
I had a 99 Formula with automatic and hung out with a bunch of other F-body people. The 6 speed people seemed to have problems with missing shifts and bumping the car off the rev limiter. In the short term that bends pushrods and in the long run it means the drivetrains were used and abused more than most other cars.
Take a look at the wrecked car and see if it had an intake and headers. If so, I would avoid it just on the general principal that it was probably used hard. Rebuild of the engine or transmission is going to run up the total cost a bunch.

I bought a 80000 mile drivetrain from a car that was 100% dead stock. After I got the drivetrain and removed the transmission I was super happy because the car has the factory clutch and it is not even worn out. A real good sign that the car was used as a daily driver and not thrashed by a hot rodder.

 

Funky valve covers, yes. But the power outputs published in the book I have (How to Build High Performance Chevy LS - Will Handzel) the power numbers are the same for a 98-00 Camaro/Firebird, and then went up 5 hp/tq in 01-02.

One off PCM that year, and it's a bit bulkier, but not heard of issues with it.

I think they had weaker rod bolts that year, so could be some truth. If you track it, drive it hard, or it has high miles, could be a ticking time bomb.

For my own 98 LS1, I would consider doing CNC heads/cams and then rod bolts on the engine next winter.

 

Don't trust rated output. I'm just telling you what it is in the real world based on actual experience. You can accept it, or not, up to you.

 

I was a member of an F-body club from 99 thru 2003 and had a 99 Formula. A number of members had 98 thru 2002 F-bodies. We did several dyno days so I saw chassis dyno results on the same machine to get good comparisons.
The 98 cars did seem to be down a bit on power and the guy running the dyno facility claimed the 98 had different injectors. My 99 and a 2001 SS were the two strongest automatics but even the weak 6 speeds would put down better numbers than the automatics on the dyno, which I presume had to do with drivetrain loss on the different transmission types.
Dead stock mine did 314 at the rear wheels but I saw several 6 speeds that did 330 or better on the same day as I did mine. Also, mine seemed to pick up about 20 HP at 15,000 miles over what it did with 2500 miles on it. My best time at the 1/4 mile was 13.23 at 106.5 mph and no problem with wheel spin. The 6 speed guys would do high 12's and about 5 mph higher trap speed but they had a lot of trouble bumping off the rev limiter and bending pushrods.