Actually, if you read a little bit, you will see that the flat top pistons difference in volume from the dished pistons volume is greater than the 3cc gain in combustion chamber volume. Hence the .5 point increase in static compression ratio from 9.4 to 9.9. They Do Gain Compression, the L33's and new LY5's (the 5.3's in the 2007+ NNBS trucks) that is.

 

Exactly, i was just ready to comment about that , its in the flat top design and conservative crevice volume of the newer 5.3 pistons. My opinion is that the .5 point in compression is almost as important as the flow gains of 243 heads over the previous 5.3 castings. The chamber of the 243 is somewhat shrouded by the small 5.3 bore. Not sure how much that hurts gains...

 

I was thinking about a turbo system in my '08 5.3, but after seeing these results this is very impressive and costs a whole lot less! Do you think that cam is too big for an extended cab z71? I'm looking to have at least 350hp daily driven. Don't mean to hijack the thread guys.

Keith

 

the truck drove great.. this is an all around cam i advise everyone to use for a starter cam... idle needs to be set around 700-750 though. thats the only flaw

 

Yeah, I have a similar cam in my truck and it made great power and is VERY daily drivable. After i dyno tuned it tho. Check out my signature. The cam feels doggy down low but its just cuz it pulls SO much harder up top. I think i lost very little down low over stock.

 

congrats on the final outcome LS1Freek! Might get a custom cam made up with your specs and see how it fairs on the newer trucks

 

Thanks! Yeah I'm really happy. But most ppl don't think that my truck really made that much. It does sound a little high for an LM7 5.3, but thats what the dyno said. It may be off a little, but even at 20 hp its still impressive. But yeah, i love the cam! We never saw any knock retard with 28 deg timing, even when it was running lean. I'd definitely recommend it to any one with a 5.3

 

Hey guys, sorry for the noob question, but when you are refering to the new 5.3 to the old 5.3 what designates old/new? I would guess the reluctor ring teeth, but I am not sure.

 

on what octan did you tune Bader?

 

Read through the first 2 or 3 pages of this thread it will explain everything. The new 5.3 is pretty bad ***.
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