Generation IV Internal Engine - Anyone has a 417 ci LSx stroker out of a OEM 6 liter iron block(LQ9 or LY6)??

Anyone has a 417 ci LSx stroker out of a OEM 6 liter iron block(LQ9 or LY6)??

I was reading in the July 2012 issue of "Super Chevy" magazine in their article "LS3 vs 418 stroker". They stated that in building their LSx stroker they couldn't use a iron block, LQ4/LQ9, because you are limited to only going to a 4.030" bore size!!!! What?!?!?So they went with the LS3 block with its 4.065" bore. !! I know that this is not true and I know we shouldn't believe everything that we see in magazines anyway.

But all the same I want to build my LSx stroker out of the OEM 6 liter iron block because I know that they are way stronger, cheaper and more plentful than the aluminum block (LS2 and LS3). I know that guys out there have bored these babies beyond 4.030".

A few years ago I know that at first 402 ci strokers(with the 4.00" bore) were all the rage then they were followed by the 408 ci (with the 4.030" bore). Remember those SLP short and long block packages? But there has got to be quite a few of those big bore big inch LSx strokers in the 415 ci to 417 ci range out there running around by now.

If you have one of these 415+ ci iron block babies withthe 4.00" stroke, please post your experiences here?? How big did bore out your iron block???

We went to 4.057 with mine so it would still have room for cleanup if need be. No problems at 900 crank hp.

Yes, people have bored the 6.0 iron block out bigger. But, you really should have the block sonic tested first. Not all blocks can be bored out that big due to core shifts. Calles makes a rotating assembly that is 4.060" bore and 4.000" stroke for 414 CID. That might allow a bit more safety than going to 4.070" like most of the LS3 stroker kits.

SUMMIT AND TSP BOTH !
Sell a block 4.030 bore ready for rotating assy!

Mine is 4.030 with a callies 4.100 stroke!

One thing I want know is why everyone or least alot of people are saying that for the OEM iron block the maximum bore 4.030" while they bore out the LS3/L92 block from 4.065" to 4.071"??? Why the 4.030" limit??? They both have 4.4" bore centers. The LQ4/LQ9 block is made of all cast iron and the LS3/L92 cylinder is made of soft aluminum and ductile iron. But it is safe to go with the bigger bore with the block that is made of the softer material and the the harder stuff is somehow forbodden???

I don't get it??

Please someone explain why the "hard" limit 4.030" bore for the OEM LSx iron block???

The "safe" limit for the 6.0 iron block is 4.030" which is not the same as the "maximum" limit. The safe limit means all of those blocks can be bored to that size without any adverse effects. I also would not go bigger than 4.030" if you plan to use a power adder.

Like I said in my earlier post, people have bored this block out to 4.060" or 4.065" or 4.070". But, you really should have it sonic tested to make sure you don't have a block with a core shift during the casting process. If that happened, you could have some thin walls in a place or two if you go too big.

You can't compare a cast iron block to an aluminum block with cylinder sleeves. Heck, if the LS1/LS2/LS3 is resleeved, it can support a 4.125" bore.