Alright I'm stumped! My temp gauge after about an hour of driving around will read just below the 260 mark. Wehn I pop the hood I hear no boiling and when I check the hoses they prove no boiling liquid. Both fans run and plenty of air is flowing. But still the temp gauge inside on the dash panel reads just below 260. I have a 195 thermostat in it and have just recently replaced the water pump. The pump works as wehn the radiator cap is of the anitfreez is flowing. If anybody can help me out I would greatly appericate it. thanks Keaton

 

There are two separate temp sensors... one in the drivers head for the dash gauge, and one in the water pump housing for the PCM. If you put a scanner on it, you can see if the PCM sensor agrees with the gauge sensor.

Or, you could remove your gauge sensor and measure the resistance at various temperatures, to see if it is accurate. I can give you a link to a page with ohms vs. degreesF for the sensor, it you want.

Just curious... stock t'stat is 180degF, most people opt to drop to a 160degF 'stat. Why did you use a 195?

 

another qestion is , did he use the correct t-stat for the LT1?

 

I dropped the 195 in there because chevy told me the LT1 runs at it best around 200 to 220 they said a 160 or 180 was way to cold for it. Thats why I went with the 195

 

well bud they lied..LT1 makes its HP best at around 176..i keep mine around there and never go above 185

u sure you have a reverse flow thermo in there bc thats what the LT1 takes

 

I have no idea if it does or not I went up to the local autozone and got the 195 temp and its a duralast. Now that I know that though I will go to a 160 thermostat. Just curious on your temp gauge where does ur needle usually run at?

 

If you went to AutoZone, I'll bet you 100:1 odds that they gave you the wrong t'stat. Could be contributing to your problem. Shoebox has info on his page regarding the differences between an LT1 t'stat and a "normal" SBC 'stat.

http://shbox.com/1/tstat.jpg

The problem with listening to most of these "mechanics" is that A) they are not aware of the reverse flow cooling used in the LT1, or B) they don't understand the implications of reverse flow cooling.

Think about it... if "chevy" thought the LT1 ran best with a 195degF t'stat, why did they install a 180 at the factory? And, the t'stat doesn't control the engine's operating temps, the fans do. Even with a 180 or 160 'stat, the engine will run around 210degF with stock fan on/off programming. That's just about the middle of the gauge. The stock programming doesn't turn the first fan (or low speed 95+) on until 226degF and the second fan (or hi speed) untill 235degF.

There is validity to running the engine at that temperature, in terms of fuel economy and emissions.... both will be better. But for max power, its been shown that reducing the temperature will increase HP. My engine was tuned on an engine dyno, and we run it at 192degF.... best for peak power in my particular setup.

Lowering the coolant temp actually reduces the thermal efficiency of the engine, reducing power, but this loss can be offset by reduced air charge temperature and a touch more ignition advance.

 

restripe--quarter tick for me is 82degrees C which is 180 thats where i run first tick driving around and and a little under while cruising in cold weather..i also run 80% distilled water 20% coolant..my fans are programmed at low (1fan) 180 and high (bothfans)at 190 which it never gets to...i also have manual fan switches in the dash which allow me to cool whenever. I read that LT1s love hot oil and coolant temps of around 176 to 185..different coolant temps will benefit for different setups as fred said..i believe for my bolt on car 180 is ideal

 

Thanks so much for the help i just got back and went and got a 180 from the dealship screw those othe rplaces lol. Agian thanks for the help guys!!!!!