ls1 to ls2 swap

[JEFF01Z]

I need a little info on which route to go. I have read some info but not all my questions are answered.

What is the weight difference between the iron and the alum blocks?

I know on the iron block that the accessories don't bolt up exactly without drilling out and tapping. Is this also the case on the alum. block?

Knock sensors. I know the knock sensors do not mount under the intake on the LS2, is this the same case on the iron block? Is it a big deal to relocate the wiring from the ls1 harness to the new location?

I am assuming that you can use the ls1 harness and PCM and just tune it?

I am leaning towards the iron block since it's potential is greater. I have even had thoughts of using the GMPP LSX block because of the potential of 483cid. Doubt I will go that way, it is way to expensive.

[Firebirdjones]

I have looked into this as well for a while. I am like you and lean towards the iron 6.0 block for many reasons.
One being that a brand new iron block is only $600. The biggest reason I lean towards it is because of easy boring, plenty of meat without having to mess with sleeves and what not. That has always been a big turn off for me on the aluminum blocks. I always think long term and how many rebuilds I can get out of a block in the future. If I am going to pay money for blocks, cranks, heads etc.....I want to be able to freshen them with minimal hassle due to wear and tear or something unexpected happens.
I build them to drive everyday and wearing one out and rebuilding again is always on my mind. I won't pay for a new block unless I know there are at least 2-3 rebuilds in it without sleeving.

With that said, there are other issues as well. The weight difference isn't enough to shy me away from the iron block. In some articles I have read they claim only about 75 lbs. weight difference between a bare iron and bare aluminum block.

As far as tuning one, your Fbody computer should work so long as your crank shaft has the same tooth count reluctor ring for the crank sensor.
I believe the 6.0 aluminum engines changed to a reluctor wheel with twice the tooth count and requires a computer change. So you have to be carefull of that. If you are building an engine from scratch and buying a rotating assembly to stick in a bare block then this would not be a concern for you, as rotating assemblies are available in both configurations.

Yes the knock sensors were moved and are no longer under the intake. This is easy though, as I believe there are several vendors now that offers an extension harness to reach the new sensors, and is simply a plug and play deal as far as that goes.

As far as accessories bolting in different places and some holes not being where they need to be? I can't answer that one but hopefully someone will chime in,,,,there have been a ton of people swapping to the iron block and building 402/408 strokers for Fbodies that should be able to answer.

I would think that,,,,,,as popular as this swap has been over the last few years that there would be a sticky on all things required with tips and hints

I do know in the future when my LS1 shows signs of being tired, I'm going straight for a brand new cast iron block, and stroker rotating assembly.