Flex Fan Update

[87chrycon]

OK, so i searched for an hour trying to find the topic that i followed a year ago when I installed my flex fan to replace stock electric fans. I wanted to add this information to that topic so people would have this info at their disposal but came up empty on the search. Here is a not so brief description of what I did and what I have found.

 

I have removed and replaced the stock electric fans with a flex fan and spacer right on the water pump/pulley. I have a fan shroud from a conquest that ran a clutch fan installed on the radiator for "guiding" the air through. The flex fan is installed as a puller meaning it pulls air through the radiator. In hot summer temps I love the performance, stock temp guage never exceeds 1/3 on the guage. Runs very normal temps and my (AEM)wideband shows that the stock 88 ECU (car is an 87) that i use is recognizing warm loop and fuel mixtures are right on (14.0--15.3 and searching for stoich).

 

Last year when I did the swap to the flex fan/shroud, I never drove the car in cold weather as I stored it for the winter (and I did not have a wideband operating for fuel information). Now that I have the wideband operating and I have driven the car in the freezing cold temps (15* F), I have noticed that the car is warming (slower traffic) then returning to cold loop (stock guage clear down by the C) when hitting the interstate. This may not seem like a big deal as it is better to run cold than to run hot but it is causing the ECU to recognize cold loop and add fuel and creating a rich condition way too often. My wideband is often showing 10.0--11.0 fuel mixtures. It is eating gas like crazy and killing my mileage, not to mention if you run rich constantly it is going to thin the oil out as the mixtures will get past the rings and eventually engine damage can occur from the rich conditions and diluted oil.

 

So there is an update to a thread I could not find. Just my 2c of information for those running these mods. If you do not have a wideband and you are seeing below normal fuel economy, colder temps on guage, this could be the problem. I will remove the shroud this week and see if that keeps the temps warm in the cold weather. I will also update this post with my findings after removing the fan shroud.

[strang3majik]

clutch fan may help that, that way its not spinning at engine RPMs. Edited December 5, 2009 by strang3majik

[87chrycon]

ATTN: moderators... if you want to move this to advanced virtual mechanic please do....I thought I posted it there!!

[D_Venable]

what t-stat are your running? If your running a 180° one, I'd recommend switching back to the OEM temp one, which is a 190°

[Indiana]

Yes, get an OEM thermostat.

 

192 degrees, it will better regulate flow which is all a thermostat does

 

http://www.b2600turbo.com//images/IM006083.JPG

 

http://www.b2600turbo.com//images/IM006084.JPG

[Cobalt60]

I will remove the shroud this week and see if that keeps the temps warm in the cold weather. I will also update this post with my findings after removing the fan shroud.

 

Definitely keep us updated. I am again thinking about doing this, and if running with no shroud works, that saves me most of the hassle on my end from doing this. I believe someone (maybe you?) said they were running with no shroud during warmer weather and it was working fine.

[ucw458]

1 Too cold is actually bad for engines. Metal 2 metal wear (rings for example) happens 100x faster on a cold engine. The greatest engine wear comes from right after you started it. Even 165 is a little too cold. Use the OEM 190 deg thermostat.

 

http://www.gi.alaska.edu/ScienceForum/ASF7/747.html

 

 

 

2 Flex fans suck. No matter what one you get it will eat HP. Flex fans are a cheap band aid for a poor cooling system. Get a clutch driven fan. You will regain some lost HP and it will allow the fan to "slip" when cold so it wont overcool the engine.

[Komeuppance]

Electrics FTW.

 

-Robert

[87chrycon]

Sorry it's been so long but I've had family health issues to deal with and the winter weather has been CRAPPY......, to make a long story short it snowed about 5x (about 3 feet total) since I posted and I have not driven the car--sucks when I have to put it in storage.....but it is warming up this week and I will get the shroud off of it and see what happens when it gets cold out again.....I may put the clutch fan I have on, and reinstall the OEM t-stat as well but I will do these all seperately so I can seperate the feedback I get from each mod......sorry about the wait but I don't drive it in the salty s*** here in Omaha! I'll try to get an update on this over the next week or so......

 

The flex fan is loud but I have 3" turbo-back exhaust as well......and the exhaust is NOT quiet.

 

To the guys that are constantly knocking the flex fans......My cooling system is a 10 out of 10 as the radiator/hoses/clamps/sensors etc. are all new or in perfect working order--they've all been bought by me or removed and checked by professionals or myself......I removed the electrics because I don't trust the (old) wiring on this car and someone on here wanted to swap me a shroud and clutch fan plus give me $50.00. The car never overheated to begin with I just made a change because I wanted to--and I wanted it to be quick. If I wanted a 300+HP conquest or starion I'd go the cheap route anyway and put a Chevy 350 4-bolt in it. I don't need an extra "race car" as my V-8 Datsun will outrun 95% of ANYTHING that I see on the road--I wish it had a flex-fan on it so I could talk some crap but it has dual electrics......I would be surprised if anyone could tell me how much HP on average an engine loses when replacing electric fans with a flex-fan anyway, anybody know the answer to that......?? Just my 2c.