Ls3 bottom end w/243 head question
#1
Ls3 bottom end w/243 head question
I have an 04 CTS-V I recently scored a LS3 short block. I want to put my 243's from my LS6 on the LS3. My heads have been decked 20 thousandths, stock head gaskets. I have a TSP 228R cam does anyone have an idea where my compression ratio would be?
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I calculate closer to 11.3 static CR. The cam overlap is a big factor in calculating dynamic CR. If this is with a stock cam, you might be on the edge with pump gas unless you use 93 octane.
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#8
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I have a LS3 bottom end and 243 heads with a slightly larger cam. my heads were decked .025 and to get compression around 11.6 I had to get a custom cometic gasket at .070. I think you will be fine with what you have.
#12
found this thread doing a compression ratio search. having an engine built right now for my project car and i was discussinf CR tonight with my guy. says my setup is 11.5:1 instead of the 12.5:1 i initially though it was going to be. I was told that the 11.5 is better given i will be using this car primarily for the street and if the wife god forbid doesn't catch the idiot attendants (yes, in NJ you cannot pump your own gas....very lame) i would be in a better position if i didn't realize and started beating on it. I was also told it would be max 20hp difference in the higher CR (from 11.5-12.5) given the variables . when it is tuned i will be tuning it on WaWa 92 octane as another failsafe just in case. So i will be able to tell you how running on less than 93oct ends up. I will also be tuning for 100 octane just to compare differences for future reference/builds. it really pays to have a good friend with a mustang dyno lol.
if this were a pure hobby/show/track car i would've gone ridiculous cam (if i kept it NA like i did now).
In other words, you're more than fine with the 11.5-6:1 lol
nothing, unless you're going over 400cu. that's where the L92's really pick up steam (from what i've heard, wtf do i know? lol)
im sure there's threads on this forum but here's a quick interesting read
http://www.yellowbullet.com/forum/sh...=473542&page=2
if this were a pure hobby/show/track car i would've gone ridiculous cam (if i kept it NA like i did now).
In other words, you're more than fine with the 11.5-6:1 lol
What's wrong with cathedral port heads?
im sure there's threads on this forum but here's a quick interesting read
http://www.yellowbullet.com/forum/sh...=473542&page=2
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I'll be doing the same thing on my 418 ls3 motor. AI 243 heads and Fast92/92 combo with a texas giant cam. Not optimal heads but since its the setup I have its what I'm going with. Once I get it broken in and tuned well I'll post up some dyno numbers. I wont have any track numbers since there isnt one here....If it makes 500/500 through my 4k stall I'd be extremely impressed!