Went out and let her rip for over an hour on 80 degree temps outside. The experience has been very different from the stock t-stat and no fan switch in my 90 L98. Its a consistent SOTP performance difference under spirited driving conditions out on the open road as well as launching from stop signs and lights. Strange strained heat-related noises under the hood have stopped too. This thing is running REAL COOL now & I'm elated! :hurray: I installed a 160 degree t-stat & fan switch that's supposed to turn on BOTH fans at 200 degrees, then off at 185. HOWEVER - it sure seems like they go on a heckuva lot sooner than that!

A couple questions:

1. The guages in the 90 don't pinpoint accuracy very well, so its guesstimates.......Before the install, once fully warmed up the oil temps were about 180+ degrees, and the coolant temps always reached about 230-240 until both fans sequentially went on. Now the guages are on the other end of the scale......about 130 for oil and 160 for coolant - this is tops after driving hard and idling at stop lights for good periods of time. Is this consistent with others who did both fan switch & 160 degree t-stats? This seems quite LOW!

2. Could the install of fans switch + 160 t-stat actually have caused the oil & coolant guages to somehow go a little haywire?

3. Is 160 t-stat bad for longevity of the L98 engine? I'm not trying to be a racer, just a daily driver who likes to step on it at times (don't we all). My goal is to keep this car as long as possible. Would it be better to stick with the super cool 160, or install another one, say 180 degrees instead?

Prior to the install, I was paranoid at the ridiculous high coolant temps and had to put an end to it. NOW I'm wondering if I'm running too cool for the L98 to have a healthy long life for the opposite reasons. Am I nuts? Thanks! This while thing confuses me at times :crazy: I need some good technical and practical advice!



[Modified by bradvette, 12:42 AM 6/11/2003]

 

I did the Hypertech 160F thermo and Programmer which set my reset my fans. My water temp matches yours but the oil still comes up to about 185F under normal driving, 215F or so under "Spirited" driving. I don't think I would trust the oil temp you are seeing but who knows? :confused:

 

I have a 90 too....
The oil temp is allways under 180.... even in these very hot days (95°F !!)
It seems (the '90 model gauge) it reads a little under the real temp.
The water temp with my on-off switch can stay from 180 to 200.
-Beppe-