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Discussion Starter #1
Have been running a factory ls7 in a late model camaro drag car "6.17 1/8 time". I am going to refresh the ls7 this winter. It has the 3959180 cam, I am thinking of changing to a crane 131311 /springs and lifters. No other changes other that rings and bearings unless I find a problem. Does the crane 131311 look like a good choice or am I going backwards from the 3959180. Any opinions are welcome, thanx. JOE
 

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Hammer and a torch
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If you want to stay basicly where your at now then that is a good choice... Might even perform a little better maybe a tenth...? While its down I would do clean up work on those 990 heads for sure they come alot of casting flash in the runners & bowl area`s, then shape the chambers to get rid of the sharp edges just outside the valve seats but dont port them (no need too)... :thumbup:

LS7 BBC is still an awesome base bracket engine package... ;)
 

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http://teamrfc.gospelcom.net
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One of the major differences between these two cams is the ramp rate. The 131311 has more lift, but less duration at .050. This is one of the benefits of newer cams. I agree that it may be a little hard to determine exactly how much it would pick up in the 1/8th. I do think that it would gain responsiveness though. What is your stall speed and compression?

Adam
 

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Hammer and a torch
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Dont know his stall speed but the compression on an LS7 crate engine is 12.25 to 1... (big heavy pistons with knots that look like your wife took a baseball bat to your head...) :D
 

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Discussion Starter #5
I think the stall is around 4500. Yes I noticed the large knots on top of the pistons :D . Not really looking to gain much, If I do great but I wont be mad if it still runns a 17. I hated to even fool with it. I was dead on between a 6.17 and 6.22 all last year. If I could get the tree under control I might bring home some money one day. Thanks for the help. JOE
 

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QUOTE: If I could get the tree under control I might bring home some money one day

I hate to be a wet blanket, but invest in one of those porta-trees from summit, the mom-n-pop speed shop on the corner, etc. Once the reflexes are finely tuned and the LS7 gets boring, then stuff a new bumpstick in it. Just my advice.

If you get bored clean up the heads like someone said; removing casting flash and smoothing out the combustion chamber can only help swirl/flow.
-Matt
 

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Although I dont know for sure what difference the cam will make, I would really like to know. This would be a really good comparason between older style cams and newer cams with newer technology. I bet that even with less duration, it will make the car faster, especially if you have a heavy car.

Adam
 

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Discussion Starter #9
We run mostly in mobile, Hattiesburg,Battles. But would like to travel some this year. The ls7 car is not mine. I let a friend use my user name to log on and ask his questions. I sold my vega last year and building an s-10 now. Putting his car on a diet would probably get him in the 5's. Its just a back half iroc/cage.

 
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