im picking up an 04 5.3 for my 98 but i want to build the truck into a puller and tower how far out can i bore it and what about a stroke kit? id like to maybe do some ls1 parts would a bore and stroke be good? im looking to get around 400hp and 500 torque.... any help is appretiated thanks

 

Only way your going to get close to that tq, esp down low is with a blower set up. No amount of stroke will net you that gain in that low of a rpm.. Unless you build a HUGE cubic inch engine.. Also if you are only into towing and not racing, running a smaller primary header will yeild you a few tq points down low

 

5.3 bore to ls1 specs - crank/rods are the same, just the pistons changes..


the only way to get to 500 tq/hp , like mangled03gmc - is with a blower-

212/218 - 561 or 581 , seem to be working pretty good on tq, and doesnt required as big of a stall .
gl on ur build

 

Here's an idea for you, only because I think it's what I'll end up with some day.

Aluminum 5.3L block, Wiesco flat top (-2cc) 3.800" bore 4" stroke pistons, K1 or Callies 4" stroke crank, Worked set of 243/799's (stock valve sizes, ported, bowl work, transition work, and really good valve job) decked to bump up compression (probably around 10.7-10.9:1), custom specified camshaft (212/224- ~.575 lift ~115), custom set of stepped long tubes 1.75" to 1.875", and top it off with a TBSS/NNBS intake manifold. Tune and have fun. Not 500 lbft. at the wheels, but it should put out substantially more torque than a LQ9 built due to the 4" stroke, and you can brag that it's a "5.3", just look at the block!

Note: I suggested staying with the smaller bore over punching out to 3.898-3.905 so as to leave some insurance if I later choose to add a TVS 1900.

 

I have a bored and stroked 5.3 (383ci) in my p/u and its a torque monster. haven't got it on the dyno yet so i have no hard #s, but we will see soon enough.

 

I was wondering about this combo, I knew that it could be bored to a 5.7 bore (3.90"), I figured if a 5.7 could be stroked to a 383 so could this block. What heads are you using with this? What compression do u have? I'm interested in this, but would it be cheaper to use a 6.0 block.

 

243 heads, 10.5:1 compression. Bore - 3.905, Stroke - 4.0 , You could probably do a 408 cheaper than a 383 but that depends on how much you pay for your block and how much you pay for your machine work.