How durable are they? They are 2 bolt mains? What can they handle up to how much hp? thanks

 

LT1 blocks?

 

Wrong section if you are really asking about the LS1 or are you mistakedly refering to LT1?

 

Last I checked, LS1 blocks are 6-bolt mains.

Not sure why this was posted on "LT1/LT4 Engine Tech".... moving......

 

They are also 6 bolt mains because it's an aluminum block. Everything pretty much evens out.

 

A local ran his stock block, stock crank LS1 to well over 1000hp without breaking either part.

 

There was a NICE black SS in one of the latest issues of GMHTP, running 1000 hp w/ a blower. For an FI motor, the breaking point is 'typically'....I use this term loosely... 600-800hp Blown, 8 lbs of boost w/ a mild cam and heads. Usually, heads aded to a cam and blower motor will throw #7 out.

And yes, 6 bolt main. They're worth rebuilding w/ forged internals, if that's what you're getting at. Just can't punch it out. Have to get a re-sleeved block, or a C5R block.

 

There are plenty of cars running 11's and 10's w/the stock rotating assembly in the stock block. Thats durable enough for me.

 

I have seen a few Camaros run high 10's with just a CAM on a stock block, stock heads, and stock internals! That is pretty good in my books.

 

I don't know if I agree with this.

 

Care to expand on this?

 

The LS1 main caps are powdered metal and significantly stronger than the LT1’s cast caps. A total of six bolts retain each main cap to the block, including the two cross-bolted fasteners.

So a beefier main cap and 4 more bolts than an LT1, 2 of which are perpidicular to the others and go through the engine skirt.

Just because it is steel, does not mean it is automatically stronger than Al. There is more to mettallurgy than that.

The LT1 has nothing on the LS1 when it comes to the bottom end.