i just finished disassembling the 6.0 i plan on swapping into my 94 k1500, and have a few questions about parts i am replacing.

most of the internals will be stock replacement in order to keep the cost down. however i do want to swap the pistons for flat top ones. my question is will that make the compression ratio to high? i still want to be able to run 87 octane. i'll be running the stock heads with just a polish.

as far as the cam goes, im planning on using the stock one for now unless i can find a good one that wont break the bank. i am swapping the valve springs for ls6 ones.

any input or suggestions help, thanks.

 

Flat top pistons and stock 317's, with no mill, will yield 10.08:1 static compression, which is what the LQ9 has, and the factory recommends 91 octane for the vehicles equipped with the LQ9. More than likely the heads are going to need to be milled, which will bump the compression even more. I remember reading here about guys trying to run 87 in bone stock Silvy SS's and the engines would ping, so I would have to say that 87 probably won't work for your application.

 

so would i be better off just staying with dished pistons, if the heads need milled?

 

Considering that you want to stick with 87 octane gas, I'd say yes. If you plan on eventually installing a decent size bumpstick you're going to want the extra compression though, because as the cam overlap increases, the dynamic compression ratio goes down (which is why you may notice that some cams are listed as requiring at least 10.5:1 compression in their descriptions )