I have a 91 formula with the L98 and just wanted to get an opinion from you guys on the best operating temps for my car. Currently my car will get to 225 at idle and drop to ~220 after the fan turns on. When driving, it will drop to about 180. Considering this is the way the car was set up from the factory, should I leave it this way or should I get the fan switch that will turn the fan on sooner? What is the best temp at idle to shoot for with this car? Thanks.

 

I have a '91 Z w/L98 and mine usually runs about 160 on a warm day (w/195* stat), but when sitting in traffic, etc., it climbs on up to 200* or so. GM designed the system to run at about 239* or so, but that's awful damn hot, in my opinion, so like several others, I changed the fan switch to 200 on / 185 off. I don't care to have my engine running at 225*, but if I were you, I'd change the switch also. It's located between the #6 and #8 plugs on the pass. side head...

KAM