I have a 1998 5.7 Vortec roller cam motor. long story short I need to rebuild and bore cylinder due to scratches. I was wondering if anyone has experience with replacing factory dished pistons with flat tops valve releif. I run premium gas anyways so not too worried about that. My concern is more will the stock computer, TBI work or will I require some type of tuning? The vortec heads are shaved .015. I have heard that you can do flat tops and CR will be close to 10.4:1. I have also heard that I would need to use a LT1 knock module. I have also hear that I can use everything stock TBI, Knock, etc with no issues. I was planning on using factory everything cam included just adding flat tops. Has anyone put flat top pistons in a vortec 5.7 if so any advice?
Additionally without O2 sensors how does the computer control Air/Fuel mixture? I understand that we have a map, knock etc but I don't understand how the computer knows if it is rich or lean and how to adjust?
All help is greatly appreciated
thanks
Additionally without O2 sensors how does the computer control Air/Fuel mixture? I understand that we have a map, knock etc but I don't understand how the computer knows if it is rich or lean and how to adjust?
All help is greatly appreciated
thanks
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