I have a 2002 Pontiac Trans Am with a 5.7 L LS1 motor and I知 wondering how much can the stock block hold, because what I was planning to do was rebuild the whole engine and put performance mods all on the car and I知 just wondering how much horsepower they can hold or would I have to swap the block out. Sorry if this is not meant to be here I just signed up for the site.

 

The block will take pretty much whatever you throw at it, unless you are taking it much past 800HP.
How high do you plan on going?

 

i知 planning to make roughly 600- 700 if that

 

If the block is sound, you're good.

 

The stock LS1 block can handle that, the stock rods and pistons might not though.

 

Isn稚 the LS1 block the strongest of the GM aluminum ls blocks?

 

Good point. He was asking about the block, so my tunnel vision focused only on that.
A good set of Gen IV rods would do it.

 

I was planning on getting forged anyways for it, I知 completely rebuilding the whole motor and trans to hold that power

 

If you're asking this question on an Internet forum, the answer would be, it'll take as much up as you can make it produce, assuming no build malfunctions. Not something you have to worry about.

Not completely sure what "up" is although I'm going to give the benefit of the doubt and grant that it's a typo.

Now, horsepuckers might be a different question... probably only will withstand 1000 or so of those, depending of course on how long that has to go on to be considered "take". Once? Drive it to work every morning? Saturday nights at the strip? Gonna be on Memphis Outlaws? There's different definitions of "take" as well.

Since this is your first motor build, I'd recommend focusing on motor building techniques, as opposed to any sort of "capacity" the block may or may not have.

 

I am about to find out....wish me luck!

 

it痴 gonna be a street car but I知 gonna not cut corners and build it right no matter how much of a money pit it may be

 

I have never seen a block fall apart on someone even in the 1,000hp range. I was making around 1,000hp on mine and that was years ago, the guy who owns it now still is driving it and that was almost 10 years ago. I was spinning 7,000rpm drag racing it and never had anything except valvetrain issues. So I would imagine the block is fine. I personally have never seen one come apart, unless it was internal engine issues.

 

Which block does your 2002 Trans Am have?

About 20% to 25% of 02 cars got an LS6 block instead of an LS1 block. The LS6 block is revised to be more high RPM friendly but isn't quite as strong. Back when sleeving LS1/LS6 blocks was popular the LS1 block was preferred.

For brief periods like drag racing etc I've read of LS1 blocks living at 850-1000 hp - of course no promises

Rest of driveline will need to be upgraded accordingly. 450 whp can be challenging to hook on the street in a street car....never mind hooking 1,000 whp etc in the daily driver. Probably ought to define street car as that word really means something different to each individual.

However, if money isn't a limit as mentioned dump the 02 TA's engine and get a Gen IV 5.3 block etc ad many other GM blocks are better foundation to build on than the original LS1 block. A RED sleeved 5.3 or LS2 block would be pretty choice if using a factory block.


Another question is do you have an expert engine builder and master tuner to work with? Bad tuning kills a lot of engines. Marginal builders kill a lot too.

Bang for the buck a 5.3 Gen IV out of a junkyard with a few updates is pretty hard to beat for forced induction.