ls1 timing problem
#1
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ls1 timing problem
hello, ive recently installed a new comp cams cam into my Camaro and have run into an issue while trying to start it. I lined up the timing marks during the install but when you try to start it, it backfires through the intake almost immediately and pretty badly. any ideas of why it would be doing this?? is it possible I timed it 180' off?? any insight is appreciated, thank you.
#2
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Sounds like you are on the right track. My father always warned me of this exact situation so likely worth checking. Maybe check your cam and/or crank position sensor(s). There is a crank position re-learn procedure but I don't think it would help such an extreme issue.
Did you change anything else? Did you get your pushrods and all set up properly? Backfire like that could be caused by pushrods too long and intake valve(s) not closing all the way.
How possible is it that you set the cam wrong?
Did you change anything else? Did you get your pushrods and all set up properly? Backfire like that could be caused by pushrods too long and intake valve(s) not closing all the way.
How possible is it that you set the cam wrong?
#3
cam timing gear should be 6 o clock and crank timing gear should be 12 o clock, and in this position cyl 6 is at TDC on the compression/power stroke and cyl 1 is at TDC of the exhaust /intake stroke. In other words cylinder 6 is ready to fire. The cam sensor tells the computer which stroke the engine is on. so if you installed the cam 180 degrees out the computer will identify the problem the engine will run. So I agree with Mercier check your pushrod length or maybe the cam is installed totally incorrectly.
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Sounds like you are on the right track. My father always warned me of this exact situation so likely worth checking. Maybe check your cam and/or crank position sensor(s). There is a crank position re-learn procedure but I don't think it would help such an extreme issue.
Did you change anything else? Did you get your pushrods and all set up properly? Backfire like that could be caused by pushrods too long and intake valve(s) not closing all the way.
How possible is it that you set the cam wrong?
Did you change anything else? Did you get your pushrods and all set up properly? Backfire like that could be caused by pushrods too long and intake valve(s) not closing all the way.
How possible is it that you set the cam wrong?
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I had a similar thing happen once putting on heads. After pulling the heads again thinking I did something wrong I noticed on my log that my IAT was way, way off. Turns out I forgot to plug in the IAT sensor and it was fueling like it was -40* out. Plugged it in, no more bad backfire.