M8 Engine Temp
#21
Hi Craig. Yes your tune is spot on, the airfuel and timing are right where they need to be. Oil temp of 220 is what I would expect in our area.
#23
Join Date: Oct 2007
Location: Western South Dakota
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When they wet head first came out it was only the rear cylinder that was liquid cooled was it not?
If both are liquid cooled now and the temp is still hot then there is something terribly wrong, IMHO.
#24
People need to understand this is an air cooled engine and they will run hotter than a typical water cooled car engine. Nothing new about it at all. The problem is keeping the temperature within limits that damage does not occur. 350 head temp's will not hurt anything on an air cooled engine. I do not like oil temperatures at or above 280 but others may disagree. My testing was done to see where things were and I made changes to keep all the temperatures within a safe range IMO. You are never going to get these to run at or near water cooled car engine temperatures, the engine is not water cooled! Yes, they have cooling in the heads only, so it effects those temperatures but it is still an air cooled engine.
#25
The location of temp sensors is not nearly as important as the "impact" of the temps on the bike's performance. The simplest measure of "what temp is too hot" (beyond rider comfort) is when do the engine designers decide to take spark advance away from the engine. The attached map (which some of you are very familiar with) shows when the MoCo engine designers decided to remove spark from the ECU map based on Head temps of a twin-cooled 117 Stage 4 engine build with all Harley parts using the tuning map from HD. Also worth noting the EITMS (rear cyl cutoff) is designed to activate at 284 degrees (engine temps) and turn off at 275 degrees engine temp.
Once Head temps rise above 329 degrees, the designers elected to begin removing spark advance. Generally Head temps above 329 degrees are about equal to "Engine Temps" over 300 degrees.
Also worth noting that the HD engine designers also elected to retard spark as the "AIR TEMPS" rise.
Once Head temps rise above 329 degrees, the designers elected to begin removing spark advance. Generally Head temps above 329 degrees are about equal to "Engine Temps" over 300 degrees.
Also worth noting that the HD engine designers also elected to retard spark as the "AIR TEMPS" rise.
Last edited by Heatwave; 05-04-2017 at 12:11 PM.
#26
Probably going to get slammed for this but, other than open loop marine engines, really all engines are air cooled. Its only how the heat is radiated to atmosphere that differs.
Edit: Technically, all engines are when ya think about it.
Ok , fire away.
Edit: Technically, all engines are when ya think about it.
Ok , fire away.
Last edited by stixvrad; 05-04-2017 at 12:16 PM.
#27
Just took a 4700 mile ride to west texas along mexico border. Temps were 96-100 down there running all day between 50-80 mph. Don't know what head temps were but oil pan temps ran 219 to 228 highest and it was hot out. Have original header pipe heat was only really noticeable when going slow otherwise no big deal. Now a passenger may feel differently.
Overall bike ran great without an issue averaging 44-45 mpg
Overall bike ran great without an issue averaging 44-45 mpg
#28
Just took a 4700 mile ride to west texas along mexico border. Temps were 96-100 down there running all day between 50-80 mph. Don't know what head temps were but oil pan temps ran 219 to 228 highest and it was hot out. Have original header pipe heat was only really noticeable when going slow otherwise no big deal. Now a passenger may feel differently.
Overall bike ran great without an issue averaging 44-45 mpg
Overall bike ran great without an issue averaging 44-45 mpg
Last edited by mjwebb; 05-04-2017 at 01:33 PM.
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psc (05-04-2017)
#29
Yea I have the cooler and the temps were at 3000 ft altitude so that's quite hot. Ran in areas northwest of big bend where it was higher also using **** 87 gas in some spots all was available. No pinging no problems very happy. Have over 6500 mi on bike now with mods in my signature awesome machine
The following users liked this post:
mjwebb (05-04-2017)
#30
Yea I have the cooler and the temps were at 3000 ft altitude so that's quite hot. Ran in areas northwest of big bend where it was higher also using **** 87 gas in some spots all was available. No pinging no problems very happy. Have over 6500 mi on bike now with mods in my signature awesome machine
Last edited by mjwebb; 05-04-2017 at 01:52 PM.