So I got a deal on 5.3 block and was wanting to do Texas speed 383 will it wrk with this block? Or better to get the 5.7 aluminum block? I'm new to this ls1 stuff

 

welcome to the forum.

there is quite a bit of info available on this forum to read on the subject. do a search on the "Generation III Internal Engine" section and you will find some good answers.

The iron 5.3 block can be bored to accept the larger pistons in the 383 kit (3.905" vs 3.780" bore), however the machining cost will be around $300. This is the setup that I have.

 

All the rotating assemblies cost the same no matter going from 383 to 416. I would sell that block and look for a 6.0 iron or alum 6.0 or larger. Going with the 4.000 bore opens up alot more head choices compared to going with the 5.3 iron or alum block.