Newbie Here - ZR-1 Net Registry Forums

QMCMSS · 05-02-2015

Hello all, I am an avid car guy and just purchased a 1991 ZR1, I am a decent wrench but my other cars are carbureted and no computer. So I'm in a new world here and after spending the last few days on this site I still have some pretty basic questions regarding the ZR1. First some background on the car. 1991 ZR1 with 51k original. It has Corsa cat back exhaust, Hailbeck Chip,and the top end has been ported and polished. It's a California car and after changing O2 sensors it passed smog. It failed on high NOx before changing the sensors. It has a high RPM miss (above 5500RPM) and seems to run a little hotter than I would like (around 220). I will be surprised if I put 5k miles a year on it with no racing expected. I do however have a heavy foot and love the way she responds.

So here is the direction I am heading

First change spark plugs to AC Delco plugs the cheapos, but one step colder than stock. Hopefully this will help with the heat and top end miss. Anyone know the part # or had experience with them. I don't know what plugs are it or when they were last changed.

Change Coolant this is my first aluminum block and want to treat it with some love any suggestions here would be much appreciated.

Change the oil and Filter to either Mobil one synthetic or Red line. Any input here much appreciated.

Thanks in advance for your wisdom.

05-02-2015	#1
QMCMSS Join Date: May 2015 Location: Benicia, CA Posts: 27	Newbie Here Hello all, I am an avid car guy and just purchased a 1991 ZR1, I am a decent wrench but my other cars are carbureted and no computer. So I'm in a new world here and after spending the last few days on this site I still have some pretty basic questions regarding the ZR1. First some background on the car. 1991 ZR1 with 51k original. It has Corsa cat back exhaust, Hailbeck Chip,and the top end has been ported and polished. It's a California car and after changing O2 sensors it passed smog. It failed on high NOx before changing the sensors. It has a high RPM miss (above 5500RPM) and seems to run a little hotter than I would like (around 220). I will be surprised if I put 5k miles a year on it with no racing expected. I do however have a heavy foot and love the way she responds. So here is the direction I am heading First change spark plugs to AC Delco plugs the cheapos, but one step colder than stock. Hopefully this will help with the heat and top end miss. Anyone know the part # or had experience with them. I don't know what plugs are it or when they were last changed. Change Coolant this is my first aluminum block and want to treat it with some love any suggestions here would be much appreciated. Change the oil and Filter to either Mobil one synthetic or Red line. Any input here much appreciated. Thanks in advance for your wisdom.