ive heard from two different people that if your engine temp is always low, that you will lose performance and will be running rich because its not hot enough to burn the fuel properly. is this true? i have my fans wired to be on all the time and the temp is always about 175-185. is that too cold? on a hotday or when i get on it, it gets to 195-200. am i losing any power or damaging anything?

also, i was showing 5* of knock retard on my scanmaster at wot with the lt4 km. i put the stock lt1 km back in there and still showed 5*. should i leave the stock one in there and sell the lt4 or put it back in? i dont know whats causing it. what can i do to get rid of it? how much horsepower am i losing?

 

ttt

 

Depends how the engine was tuned.... tuning is a matter of finding the optimum combination of spark advance and A/F ratio that maximizes torque and or HP. If your car was dyno tuned, it was probably optimized based on the coolant temperatures it normally runs at. In general, a lower coolant temperature reduces the thermal efficiency of the engine, and loses HP. But, this loss has to be balanced against any gains from a denser air charge from the lower temps in the intkae and head runners, and any possibleHP gains from additional spark advance.

Also, as coolant temperatures drop, combustion may not be as complete. Often you will see an increase in unburned HC's and CO, while there will typically be a reduction in NOx at lower combustion chamber temps.

As far as the knock, before you do anything with the LT4KM, find out why you have the knock.... is it "real" or "false"? What is your compression ratio? What grade fuel are you running? Have you tired some unleaded 100-octane fuel to see if it reduces knock retard? What conditions produce the 5-deg retard on the Scanmaster.... is it there the entire time you foot is on the floor, or is it a "recorded" value for peak retard that you are recalling after the run?

 

my compression is 10.5 or 10.8. im running 91 octane here in CA. i havent tried higher octane yet. how do i mix it when i do get some? it shows 5* all throughout the wot run. it was tuned by pcm4less. im thinking of getting a dynotune soon.