NewLS1Owner

iTrader: (6)

I have a LY6 short block that's damaged. The rotating assembly is fine though. I recently picked up a LQ4 engine and I was going to drop it into my trans am, but I think it's a pre 02 block. If that's the case, it won't work with my T56 transmission. How difficult would it be to change the rotating assemblies? Do I have to re balance it, check clearances? I'm pretty good under the hood, but I've never played with the internals of a short block before. Thanks in advance.

Shaggykjb

Question, if the "blocks" non-compatible with your t56. Why would swapping your rotating assembly matter? Is it your x53 crank that's the issue?
On a side note. I cant remember but isn't the lq4 dished pistons and the latter flat top? Could be worth it for higher compression alone.
Best of luck with the engine.

NewLS1Owner

iTrader: (6)

The crank is actually the problem. From what I've read, the pre 02 cranks where just a little bit longer to fit the 4L80E and would not fit with a T56. Both the LQ4 and the LY6 are dished. But I'll be running milled LS3 heads to raise compression.

KCS

iTrader: (20)

It's not difficult, but it is tedious. You're going to want to swap the reluctor on the LY6 crank to a 24x before going into the TA. You shouldn't have to rebalance either since you're swaping over the entire rotating assembly.

I would suggest checking clearances. If you want to add boost or nitrous, you may want an aftermarket bearing with more clearance. If you're staying NA, then the stock bearings should be fine.

gagliano7

I thought it was the 1999-2000 LQ4's with the iron heads that had the longer crank?

NewLS1Owner

iTrader: (6)

I Appreciate y'all's advice. After further research, it looks like I'm ok. It seems like gagliano7 is correct. Since my engine came with aluminum 317s I should be fine with the current rotating assembly