6.0 swap in Yukon XL, question about CR and cam
03-24-2009, 07:28 PM
#14
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Iirc high intake runner volume = lower velocity, and that means less down low where a bigass yukon xl would need more powah. Just a thought, are you considering what your dynamic compression ratio would be with that cam and 11:1 compression?
03-24-2009, 08:21 PM
#15
I have no idea what it would be. When I spoke with the guy that made that cam and he suggested a 11.1 CR and that the motor with those heads would be a home run. I am just thinking with the 11.3 CR it would be an even more badass set up. The good news is I am getting the truck tomorrow from the painter finally
03-24-2009, 09:55 PM
#16
Well, if someone can tell me what the dynamic would be and how it would affect what I am planning. The cam is a 218/224 114+2 flat top LS2 pistons, 62 cc chambers, undecked block, and stock MLS gasket. I don't know whatelse is needed I am seriously thinking for throttle response and from what I have read the 11.3 CR is going to be the ticket. Is there any reason to not run this CR? The stock LS2 in the TBSS is 10.9 so I think since they can pull it off and be as strong as they are why could I not make 11.3 worth work with a better cam and heads plus alot more time spent tuning it on the dyno? Just asking because I want this to be a great package for my wife that she nor I have to worry about. I have no problem running 93 octane because that is all it gets now. Cheveron as a matter of fact and has since we bought it. I was just going to toss in some 31 lbs 8.1 injectors. Would there be any MPG difference in the 11.1 motor or the 11.3 motor? This vehicle would be used as our traveling vehicle so I would want it to be a thrifty while being as powerful as possible. Thanks guys, I know I am asking alot of questions but I just want to make sure what I have read and been told to be factual and not BS.
03-25-2009, 12:15 PM
#18
DCR is the important thing when determining if you can run pump gas safely or not, not SCR.
The reason an LS2 can run on 87 is the fact that the DCR is low due to the stock cam. That being said, you should be able to run 11:1 just fine with a decent cam and 93 octane. Mine is 10.63:1, and now I wish I went 11:1 (that seems to be a common theme with modding, most people wish they went bigger/better the first time).
The reason an LS2 can run on 87 is the fact that the DCR is low due to the stock cam. That being said, you should be able to run 11:1 just fine with a decent cam and 93 octane. Mine is 10.63:1, and now I wish I went 11:1 (that seems to be a common theme with modding, most people wish they went bigger/better the first time).
03-28-2009, 12:19 AM
#20
Rick had the right idea. I think you should look closer at a lower compression ratio. DCR is going to be through the roof with that cam. If you travel a lot out of state you will find 93 octane fuel is harder to find and you'll have to run octane booster.