Stock LS1 bore question...

[V]

What is the stock, std. bore of an LS1/LS6 block?

More specifically, the 12561168 casting.

I've found new blocks (all same GMPP number 12561166), listing 3.900"(Scoggin-Dickey), 3.898"(JEGS), and 3.890"(SUMMIT) finished bore. GMPartsDirect says its same as 12561168 bore. Whats going on??


I have stock pistons I want to use. So I just want the stock bore as it would have came in a GM car, but I'm confused.

https://sdparts.com/details/gm-perfo...parts/12561166
http://www.jegs.com/i/GM-Performance...61166/10002/-1
http://www.summitracing.com/parts/na...1166/overview/
http://www.gmpartsdirect.com/results...umber=12561166

[NJ Torque]

I always knew it as 3.898

[greenformula92]

I think what you have here is the rounding up of the numbers

[69BirdX]

I don't think it's rounding. Because you'd been rounding .008 thousandths for 3.890. That is a huge gap on something that should have a small tolerance

[V]

The odd thing that gets me is that its all the same exact block they are selling but they are spec-ing it out different....