how big can i go on a 5.3l iron block i want to bore out to 3.903 can i and how much wall thicknes will i have?

 

all 5.3L blocks were designed to be safely punched to 5.7L Bore

 

yea but how far can i go and still be safe?

 

5.7....

 

in bore dia. and still be safe i have forged pistions that are 3.903 is that safe?

 

I'm wondering the same question not too long ago. Stock LS1 block bore is 3.898", I usually go for 3.905" bore. Given that the 5.3 has the extra thick sleeve (it was supposed to be a iron 5.7, GM designed it for the B-bodies then dumped the platform) I would say that you'd be alright with a 3.903" bore. It's only 0.0025" less cylinder sleeve. I'm bringing my 5.3 iron block to 3.905" as soon as I get the cash for it (selling my 382 setup to fund my project).

YMMV.

 

nice, im about to do the exact same thing......what are some good pistons or would you recommend the stock ones......

 

What are you going to be doing with the truck modwise? Expected power levels?

 

sweet thanks