L31MaxExpress
I'm Awesome
That flex fan will not move nearly as much air as the composite 11 blade fan on a severe duty clutch.
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But running a 160 thermostat and using a factory clutch fan don't work for me. Clutch fan kicks in too late. Flex fan keeps temps way under 180 at idle in hot temps. Clutch fans keep car cool, but also want it warmed up for emmisions and don't come on early enough for my temp requirements.That flex fan will not move nearly as much air as the composite 11 blade fan on a severe duty clutch.
Scrap the flex fan for a proper fan and fan clutch, otherwise it looks pretty good.
It doesn't matter how much air it moves, it's calibrated to what...195+ degrees before clutch fan engages? At that time, after sitting in 20 mins of stop n go traffic, my engine now is too hot too aggressively accelerate safely with timing I will be running. Clutch fan and 11 blade setup may be better, and probably is on a stock t-stat temp vehicle.I'd strongly agree with this, if only for the fact that the flex fan will kill horsepower. Engine Masters did an episode comparing clutch fans, flex fans and solid metal blade fans. They ended up in that order from best to worst in terms of power loss.
And I would agree that the 11 blade composite fan on a severe duty clutch would probably move more air than the flex fan anyway. There are two clutch fan setups for these trucks from the factory, the 11 blade composite fan and a much more common five blade metal fan. They used different clutches as well. Have you ever tried the 11 blade setup? They really do move a lot more air than the five blade.
It doesn't matter how much air it moves, it's calibrated to what...195+ degrees before clutch fan engages?
What SA maps do you have, how much timing? You can throw in an IAT which the EBL will adjust timing accordingly.At that time, after sitting in 20 mins of stop n go traffic, my engine now is too hot too aggressively accelerate safely with timing I will be running
That's "air temp" which converts to 190 degrees engine coolant temp.No, most severe duty clutches engage around 160-170 degrees Fahrenheit. They kick in way before the factory 195 degree thermostat opens.
Eventually I will be there...What SA maps do you have, how much timing? You can throw in an IAT which the EBL will adjust timing accordingly.
That's "air temp" which converts to 190 degrees engine coolant temp.
They are rated in "air temp"
I was searching lower temp engaging fan clutches, and found a few sites that show you how to modify certain fan clutches to match their 160 or 180 degree thermostats. I remember now, back in 1990 I had a 75 K5 Blazer that I attempted to modify for lower temp clutch engagement. Didn't go well, so I put a flex fan on that too. I was running a 327 Vette motor and using a 180 degree thermostat.No, most severe duty clutches engage around 160-170 degrees Fahrenheit. They kick in way before the factory 195 degree thermostat opens.