Im a newby to engine building im currently going to school to become a tech. I was wondering what is the most i could bore out of a 5.3 block. I want to turbo that block. thanks

 

Call me crazy but the most I would say would be 30 over...anymore than that and your tempting fate could run pretty thin...

Dave

 

bored and stroked can get a 408 thats what most people do. There is someone on here that has gone over that. I would be worried about going 30 over if your gonna put alot of boost to it. Id call some of the engine builders and talk to them.

 

The MAX that a 5.3 cam be bored out to is 3.905", but have the block sonic checked. That bore with a 4" stroke will yeid 383 cu in. kmtrider did exactly this setup.

A 408 is a 6.0 bored .030 over with a 4" stroke

 

thank you guys for all the help.

 

Who is kmtrider? thanks

 

Hello Silverado tur, I would say the max bore on the 4.8/5.3 blocks ( same block and bore ) is 3.905" from the stock 3.78". My min thickness after the bore was sonic checked to 0.157". Came up to 383ci or 6.3L.
The truck runs cooler than it did with the standard bore size and I have had no issues with leaks or detonation. Lots more 4.8/5.3 engines out there for cheap compared to the 6.0L models.
The 408ci motor is the 6.0L block bored out 0.040" ( stock bore is 4.00" ). Other popular one is the 402ci, again the 6.0L bored out 0.030".

 

thanks for the info. im going to send my block to the machine shop